What you can do here

Two-way conversion: type in either box and the other one updates. The middle button swaps the units.

Maths and fractions: entries such as "12*3", "1 1/2" or "½" work.

Every unit at once: the table below shows the same value in every unit of the category. Tap a unit name to switch to it.

Feet and inches, pounds and ounces: 180 cm is also shown as 5 ft 10.87 in.

Traditional units: Korean, Japanese and Chinese units such as the pyeong, shaku, catty and shō are included.

Conversion factors follow the SI and each unit's official definition, and you can choose how many decimal places to show. Copy the address bar link to share exactly what you are looking at.

Is Unitly free?

Yes. There is no sign-up, and nothing you type is stored anywhere.

My result differs slightly from another site.

That is almost always rounding. With decimal places set to Auto you see up to 10 significant digits. Values that depend on conditions, such as Mach or the weight of a cup of flour, state the assumption used.

Length units at a glance

1 inch = 2.54 cm exactly, fixed by international agreement in 1959. Screen sizes are the diagonal in inches.

1 foot = 12 inches = 30.48 cm. Heights in the US are given in feet and inches, like 5′9″. Use the height box under the converter for that.

1 mile = 1.609344 km. A marathon, 42.195 km, is about 26.2 miles.

1 shaku = 10/33 m ≈ 30.3 cm, the traditional Korean and Japanese foot. The Chinese chi (市尺) is 1/3 m, about 33.3 cm.

The quick box understands phrases such as "5 ft 11 in", "5′11″" or "180 cm to ft".

Weight units that trip people up

1 pound = 0.45359237 kg, so 1 kg is about 2.2 lb. A pound has 16 ounces.

Ounce vs troy ounce: the food ounce is about 28.35 g, while the troy ounce used for gold and silver is about 31.10 g. Choose troy ounces when converting bullion prices.

Stone: 14 pounds, about 6.35 kg. In the UK and Ireland body weight is often given in stone and pounds.

Catty: the mainland Chinese jin (斤) is 500 g, while the Taiwanese catty and the Korean geun for meat are 600 g.

Ton: a metric ton is 1,000 kg. The US short ton is about 907 kg and the UK long ton about 1,016 kg.

Strictly speaking the kilogram measures mass, but in everyday use mass and weight mean the same thing.

Formulas and reference points

°F = °C × 9/5 + 32 and °C = (°F − 32) × 5/9

Water freezes at 0 °C = 32 °F and boils (at sea level) at 100 °C = 212 °F

Body temperature is about 37 °C = 98.6 °F. A fever usually means 38 °C (100.4 °F) or more.

Ovens: 350 °F ≈ 177 °C and 180 °C ≈ 356 °F

−40 °C and −40 °F are the same temperature.

For a rough mental conversion, double the Celsius value and add 30 to get Fahrenheit. The error grows at very high or low temperatures.

What is 37 °C in Fahrenheit?

98.6 °F. 38 °C is 100.4 °F and 39 °C is 102.2 °F.

What is 350 °F in Celsius?

About 176.7 °C, so set a Celsius oven to 175 to 180 °C.

About these units

centimeter (cm)

A centimeter (cm) is one hundredth of a meter. It is the everyday unit for height, clothing sizes and furniture in most of the world.

inch (in)

The inch (in) is a US and imperial length unit, defined since 1959 as exactly 2.54 cm. Screens, waist sizes and wheel sizes are commonly given in inches.

What is 10.16 centimeters in inches?

10.16 centimeters = 4 inches. Multiply the value in cm by 0.3937008.

What is 2 inches in centimeters?

2 inches = 5.08 centimeters.

How do I convert centimeters to inches in my head?

Use cm × 0.4. For 10.16 cm that gives about 4.064 in instead of 4 in (1.6% too high).

Is 3 cm the same as 1 inch?

No. 1 inch is 2.54 cm, so 3 cm is about 1.18 in. The closest round figure is 2.5 cm (about 0.98 in).

About these units

inch (in)

The inch (in) is a US and imperial length unit, defined since 1959 as exactly 2.54 cm. Screens, waist sizes and wheel sizes are commonly given in inches.

centimeter (cm)

A centimeter (cm) is one hundredth of a meter. It is the everyday unit for height, clothing sizes and furniture in most of the world.

What is 3.25 inches in centimeters?

3.25 inches = 8.255 centimeters. Multiply the value in in by 2.54.

What is 10.16 centimeters in inches?

10.16 centimeters = 4 inches.

How do I convert inches to centimeters in my head?

Use in × 2.5. For 3.25 in that gives about 8.125 cm instead of 8.255 cm (1.6% too low).

What does a 55-inch TV measure?

Screen sizes are the diagonal. 55 in = 139.7 cm diagonally; a 16:9 screen of that size is about 121.8 cm wide and 68.5 cm tall.

About these units

millimeter (mm)

A millimeter (mm) is one thousandth of a meter, or a tenth of a centimeter, used for rainfall, parts and other small dimensions.

inch (in)

The inch (in) is a US and imperial length unit, defined since 1959 as exactly 2.54 cm. Screens, waist sizes and wheel sizes are commonly given in inches.

What is 3 millimeters in inches?

3 millimeters = 0.118 inches. Multiply the value in mm by 0.03937008.

What is 1 inch in millimeters?

1 inch = 25.4 millimeters.

How do I convert millimeters to inches in my head?

Use mm ÷ 25. For 3 mm that gives about 0.12 in instead of 0.118 in (1.6% too high).

What are common fractions of an inch in mm?

1/16 in = 1.5875 mm, 1/8 in = 3.175 mm, 1/4 in = 6.35 mm and 1/2 in = 12.7 mm. Inch-sized drill bits and bolts use these fractions.

About these units

centimeter (cm)

A centimeter (cm) is one hundredth of a meter. It is the everyday unit for height, clothing sizes and furniture in most of the world.

foot (ft)

The foot (ft) equals 12 inches, exactly 0.3048 m. It is used for height and buildings in the US and for aircraft altitude worldwide.

What is 1.7 centimeters in feet?

1.7 centimeters = 0.0558 feet. Multiply the value in cm by 0.0328084.

What is 5.75 feet in centimeters?

5.75 feet = 175.26 centimeters.

How do I convert centimeters to feet in my head?

Use cm ÷ 30. For 1.7 cm that gives about 0.0567 ft instead of 0.0558 ft (1.6% too high).

How do I give my height in feet and inches?

Divide cm by 2.54 to get inches, then take out whole feet of 12 inches: 170 cm = 66.93 in = 5 ft 6.93 in (about 5′7″). The converter above shows the feet + inches split automatically.

About these units

foot (ft)

The foot (ft) equals 12 inches, exactly 0.3048 m. It is used for height and buildings in the US and for aircraft altitude worldwide.

centimeter (cm)

A centimeter (cm) is one hundredth of a meter. It is the everyday unit for height, clothing sizes and furniture in most of the world.

What is 5.75 feet in centimeters?

5.75 feet = 175.26 centimeters. Multiply the value in ft by 30.48.

What is 1.7 centimeters in feet?

1.7 centimeters = 0.0558 feet.

How do I convert feet to centimeters in my head?

Use ft × 30. For 5.75 ft that gives about 172.5 cm instead of 175.26 cm (1.6% too low).

How tall is 5′9″ in cm?

5 ft 9 in = 69 in × 2.54 = 175.26 cm. Turn the feet into inches (× 12), add the inches, then multiply by 2.54.

About these units

meter (m)

The meter (m) is the SI base unit of length, defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

foot (ft)

The foot (ft) equals 12 inches, exactly 0.3048 m. It is used for height and buildings in the US and for aircraft altitude worldwide.

Reverse conversion: Feet to Meters

100 m = 328.0839895 ft

= 328 ft 1.01 in (328′ 1.01″)

Formula: ft = m × 3.280839895

Height (feet + inches ↔ cm)

100 m in other units

· 100,000,000,000 nm

· 6.68458712×10⁻¹⁰ au

· 1.05700083×10⁻¹⁴ ly

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert meters to feet

Start from the exact relation: 1 m = 3.280839895 ft

Put your value into the formula: ft = m × 3.28084

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1.58 × 3.28084 = 5.184 ft

100 × 3.28084 = 328.08 ft

Mental-math shortcut

Use m × 3.3. For 1.58 m that gives about 5.214 ft instead of 5.184 ft (0.58% too high).

Definition and source: 1 foot = 12 inches = 0.3048 m exactly (the 1959 international foot). The old US survey foot (1200/3937 m) was retired at the end of 2022. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

1,000 m · 3,280.84 ft

8,848 m · 29,028.87 ft

More length conversions

What is 1.58 meters in feet?

1.58 meters = 5.184 feet. Multiply the value in m by 3.28084.

What is 5 feet in meters?

5 feet = 1.524 meters.

How do I convert meters to feet in my head?

How high is Mount Everest in feet?

The 2020 China–Nepal survey height of 8,848.86 m is about 29,032 ft.

About these units

foot (ft)

The foot (ft) equals 12 inches, exactly 0.3048 m. It is used for height and buildings in the US and for aircraft altitude worldwide.

meter (m)

The meter (m) is the SI base unit of length, defined as the distance light travels in a vacuum in 1/299,792,458 of a second.

Reverse conversion: Meters to Feet

= 1000 ft 0 in (1000′ 0″)

Formula: m = ft × 0.3048

Height (feet + inches ↔ cm)

1,000 ft in other units

· 304,800,000,000 nm

· 2.03746215×10⁻⁹ au

· 3.22173854×10⁻¹⁴ ly

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert feet to meters

Start from the exact relation: 1 ft = 0.3048 m

Put your value into the formula: m = ft × 0.3048

Round to the precision you need. The tables on this page show 2 to 3 decimals.

5 × 0.3048 = 1.524 m

1,000 × 0.3048 = 304.8 m

Mental-math shortcut

Use ft × 0.3. For 5 ft that gives about 1.5 m instead of 1.524 m (1.6% too low).

Definition and source: 1 foot = 12 inches = 0.3048 m exactly (the 1959 international foot). The old US survey foot (1200/3937 m) was retired at the end of 2022. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

11,000 ft · 3,352.8 m

35,000 ft · 10,668 m

More length conversions

What is 5 feet in meters?

5 feet = 1.524 meters. Multiply the value in ft by 0.3048.

What is 1.58 meters in feet?

1.58 meters = 5.184 feet.

How do I convert feet to meters in my head?

What is a 35,000 ft cruising altitude in meters?

35,000 ft × 0.3048 = 10,668 m, about 10.7 km. Most air traffic control works in feet; mainland China uses metres.

About these units

kilometer (km)

A kilometer (km) is 1,000 meters, used for road distances and races such as the 5K, the 10K and the 42.195 km marathon.

mile (mi)

The mile (mi) is 5,280 feet, exactly 1,609.344 m. Road signs and speed limits in the US and UK use miles.

Reverse conversion: Miles to Kilometers

10 km = 6.213711922 mi

Formula: mi = km ÷ 1.609344

Height (feet + inches ↔ cm)

10 km in other units

· 10,000,000,000,000 nm

· 6.68458712×10⁻⁸ au

· 1.05700083×10⁻¹² ly

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert kilometers to miles

Start from the exact relation: 1 km = 0.6213711922 mi

Put your value into the formula: mi = km ÷ 1.609344

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1.3 ÷ 1.609344 = 0.808 mi

10 ÷ 1.609344 = 6.214 mi

Mental-math shortcut

Use km × 5 ÷ 8. For 1.3 km that gives about 0.813 mi instead of 0.808 mi (0.58% too high).

Definition and source: 1 mile = 5,280 ft = 1,609.344 m exactly (the international mile, from the 1959 yard of 0.9144 m). Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

21.0975 km · 13.11 mi

42.195 km · 26.22 mi

1,000 km · 621.37 mi

11,000 km · 6,835.08 mi

15,000 km · 9,320.57 mi

Miles to Kilometers →

More length conversions

What is 1.3 kilometers in miles?

1.3 kilometers = 0.808 miles. Multiply the value in km by 0.6213712.

What is 52,000 miles in kilometers?

52,000 miles = 83,685.89 kilometers.

How do I convert kilometers to miles in my head?

How far are a 5K, 10K, half marathon and marathon in miles?

5 km = 3.11 mi, 10 km = 6.21 mi, a half marathon (21.0975 km) = 13.11 mi and a marathon (42.195 km) = 26.22 mi.

About these units

mile (mi)

The mile (mi) is 5,280 feet, exactly 1,609.344 m. Road signs and speed limits in the US and UK use miles.

kilometer (km)

A kilometer (km) is 1,000 meters, used for road distances and races such as the 5K, the 10K and the 42.195 km marathon.

Reverse conversion: Kilometers to Miles

26.2 mi = 42.1648128 km

Formula: km = mi × 1.609344

Height (feet + inches ↔ cm)

26.2 mi in other units

· 42,164,812,800,000 nm

· 2.81854365×10⁻⁷ au

· 4.45682423×10⁻¹² ly

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert miles to kilometers

Start from the exact relation: 1 mi = 1.609344 km

Put your value into the formula: km = mi × 1.609344

Round to the precision you need. The tables on this page show 2 to 3 decimals.

52,000 × 1.609344 = 83,685.89 km

26.2 × 1.609344 = 42.16 km

Mental-math shortcut

Use mi × 1.6. For 52,000 mi that gives about 83,200 km instead of 83,685.89 km (0.58% too low).

Definition and source: 1 mile = 5,280 ft = 1,609.344 m exactly (the international mile, from the 1959 yard of 0.9144 m). Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

52,000 mi · 83,685.89 km

21.0975 km · 13.11 mi

42.195 km · 26.22 mi

Kilometers to Miles →

More length conversions

What is 52,000 miles in kilometers?

52,000 miles = 83,685.89 kilometers. Multiply the value in mi by 1.609344.

What is 1.3 kilometers in miles?

1.3 kilometers = 0.808 miles.

How do I convert miles to kilometers in my head?

Is a nautical mile the same as a mile?

No. A nautical mile is 1,852 m (about 1.15 miles) and is used at sea and in aviation; the road mile is 1,609.344 m.

About these units

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

pound (lb)

The pound (lb) is the US and imperial unit of weight, defined as exactly 0.45359237 kg. One pound is 16 ounces.

Reverse conversion: Pounds to Kilograms

70 kg = 154.3235835 lb

= 154 lb 5.18 oz · 11 st 0.32 lb

Formula: lb = kg × 2.204622622

Height (feet + inches ↔ cm)

70 kg in other units

· 0.07716179176 US ton

· 0.06889445693 UK ton

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert kilograms to pounds

Start from the exact relation: 1 kg = 2.204622622 lb

Put your value into the formula: lb = kg × 2.204623

Round to the precision you need. The tables on this page show 2 to 3 decimals.

5 × 2.204623 = 11.02 lb

70 × 2.204623 = 154.32 lb

Mental-math shortcut

Use kg × 2.2. For 5 kg that gives about 11 lb instead of 11.02 lb (0.21% too low).

Definition and source: 1 lb = 0.45359237 kg exactly, set by the international yard and pound agreement of 1959. So 1 kg = 2.20462262 lb. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

Pounds to Kilograms →

More weight conversions

Work out your BMI from height and weight →

What is 5 kilograms in pounds?

5 kilograms = 11.02 pounds. Multiply the value in kg by 2.204623.

What is 5 pounds in kilograms?

5 pounds = 2.268 kilograms.

How do I convert kilograms to pounds in my head?

How do I show kg as pounds and ounces?

Multiply by 2.20462 for pounds, then multiply the decimal part by 16 for ounces: 3.5 kg = 7.716 lb = 7 lb 11.46 oz.

About these units

pound (lb)

The pound (lb) is the US and imperial unit of weight, defined as exactly 0.45359237 kg. One pound is 16 ounces.

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

Reverse conversion: Kilograms to Pounds

150 lb = 68.0388555 kg

= 150 lb 0 oz · 10 st 10 lb

Formula: kg = lb × 0.45359237

Height (feet + inches ↔ cm)

150 lb in other units

· 0.06696428571 UK ton

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert pounds to kilograms

Start from the exact relation: 1 lb = 0.45359237 kg

Put your value into the formula: kg = lb × 0.4535924

Round to the precision you need. The tables on this page show 2 to 3 decimals.

5 × 0.4535924 = 2.268 kg

150 × 0.4535924 = 68.04 kg

Mental-math shortcut

Use lb ÷ 2.2. For 5 lb that gives about 2.273 kg instead of 2.268 kg (0.21% too high).

Definition and source: 1 lb = 0.45359237 kg exactly, set by the international yard and pound agreement of 1959. So 1 kg = 2.20462262 lb. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

Kilograms to Pounds →

More weight conversions

Work out your BMI from height and weight →

What is 5 pounds in kilograms?

5 pounds = 2.268 kilograms. Multiply the value in lb by 0.4535924.

What is 5 kilograms in pounds?

5 kilograms = 11.02 pounds.

How do I convert pounds to kilograms in my head?

Does 2 pounds equal 1 kg?

Not quite: 2 lb = 0.907 kg. 1 kg is 2.205 lb, so a kilogram is about 10% heavier than 2 pounds.

About these units

gram (g)

A gram (g) is one thousandth of a kilogram, the usual unit for recipe ingredients and nutrition labels.

ounce (oz)

The ounce (oz) is 1/16 of a pound, about 28.35 g. It differs from the troy ounce (about 31.1 g) used for precious metals.

Reverse conversion: Ounces to Grams

100 g = 3.527396195 oz

Formula: oz = g × 0.03527396195

Height (feet + inches ↔ cm)

100 g in other units

· 0.0001102311311 US ton

· 0.00009842065276 UK ton

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert grams to ounces

Start from the exact relation: 1 g = 0.03527396195 oz

Put your value into the formula: oz = g × 0.03527396

Round to the precision you need. The tables on this page show 2 to 3 decimals.

3.75 × 0.03527396 = 0.132 oz

100 × 0.03527396 = 3.527 oz

Mental-math shortcut

Use g ÷ 28. For 3.75 g that gives about 0.134 oz instead of 0.132 oz (1.2% too high).

Definition and source: 1 oz (avoirdupois) = 1/16 lb = 28.349523125 g exactly. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

More weight conversions

What is 3.75 grams in ounces?

3.75 grams = 0.132 ounces. Multiply the value in g by 0.03527396.

What is 3 ounces in grams?

3 ounces = 85.05 grams.

How do I convert grams to ounces in my head?

Is 100 g the same as 4 oz?

No. 100 g = 3.53 oz, and 4 oz = 113.4 g.

About these units

ounce (oz)

The ounce (oz) is 1/16 of a pound, about 28.35 g. It differs from the troy ounce (about 31.1 g) used for precious metals.

gram (g)

A gram (g) is one thousandth of a kilogram, the usual unit for recipe ingredients and nutrition labels.

Reverse conversion: Grams to Ounces

Formula: g = oz × 28.34952313

Height (feet + inches ↔ cm)

· 0.0002232142857 UK ton

Have a list? Convert a column and copy it back to your spreadsheet →

How to convert ounces to grams

Start from the exact relation: 1 oz = 28.34952313 g

Put your value into the formula: g = oz × 28.34952

Round to the precision you need. The tables on this page show 2 to 3 decimals.

3 × 28.34952 = 85.05 g

8 × 28.34952 = 226.8 g

Mental-math shortcut

Use oz × 28. For 3 oz that gives about 84 g instead of 85.05 g (1.2% too low).

Definition and source: 1 oz (avoirdupois) = 1/16 lb = 28.349523125 g exactly. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

More weight conversions

What is 3 ounces in grams?

3 ounces = 85.05 grams. Multiply the value in oz by 28.34952.

What is 3.75 grams in ounces?

3.75 grams = 0.132 ounces.

How do I convert ounces to grams in my head?

Is an ounce of gold the same as an ounce of food?

No. Precious metals use the troy ounce, 31.1035 g, about 10% more than the 28.35 g ounce used for food and parcels. Fluid ounces (fl oz) measure volume, not weight.

About these units

Celsius (°C)

Celsius (°C) puts the freezing point of water at 0 and its boiling point at about 100. Most countries use it for weather and body temperature.

Fahrenheit (°F)

Fahrenheit (°F) is mainly used in the United States. Water freezes at 32 °F and boils at 212 °F, and normal body temperature is about 98.6 °F.

What is 9 degrees Celsius in degrees Fahrenheit?

9 degrees Celsius = 48.2 degrees Fahrenheit. Calculated with the formula above.

What is 69 degrees Fahrenheit in degrees Celsius?

69 degrees Fahrenheit = 20.56 degrees Celsius.

How do I convert Celsius to Fahrenheit in my head?

Use °C × 2 + 30. For 20 °C that gives about 70 °F instead of 68 °F (2 °F too high).

What is a fever in Fahrenheit?

Normal body temperature is usually quoted as 37 °C = 98.6 °F; the UK NHS treats 38 °C (100.4 °F) or above as a high temperature.

About these units

Fahrenheit (°F)

Fahrenheit (°F) is mainly used in the United States. Water freezes at 32 °F and boils at 212 °F, and normal body temperature is about 98.6 °F.

Celsius (°C)

Celsius (°C) puts the freezing point of water at 0 and its boiling point at about 100. Most countries use it for weather and body temperature.

What is 69 degrees Fahrenheit in degrees Celsius?

69 degrees Fahrenheit = 20.56 degrees Celsius. Calculated with the formula above.

What is 9 degrees Celsius in degrees Fahrenheit?

9 degrees Celsius = 48.2 degrees Fahrenheit.

How do I convert Fahrenheit to Celsius in my head?

Use (°F − 30) ÷ 2. For 70 °F that gives about 20 °C instead of 21.11 °C (1.111 °C too low).

What is a 350 °F oven in °C?

350 °F = 176.7 °C; recipes usually round it to 180 °C (about 160 °C for a fan oven).

About these units

Celsius (°C)

Celsius (°C) puts the freezing point of water at 0 and its boiling point at about 100. Most countries use it for weather and body temperature.

kelvin (K)

The kelvin (K) is the SI unit of temperature. It starts at absolute zero (−273.15 °C) and uses the same step size as Celsius.

What is 32 degrees Celsius in kelvins?

32 degrees Celsius = 305.15 kelvins. Calculated with the formula above.

What is 1 kelvin in degrees Celsius?

1 kelvin = -272.15 degrees Celsius.

How do I convert Celsius to kelvin in my head?

Use °C + 273. For 20 °C that gives about 293 K instead of 293.15 K (0.15 K too low).

Why is it “300 K” and not “300 °K”?

Since 1967 the kelvin has been a unit in its own right, written without a degree sign. 0 K is absolute zero (−273.15 °C).

Input decimal separator Result decimal places

Paste a column of numbers

One number per line, up to 200 numbers and 20,000 characters. Omit headers, unit labels and thousands separators. Select the decimal separator above.

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Copying the results column preserves blank-line positions. Fix errors first. The full table and CSV include original line numbers and errors. Numbers use your chosen decimal separator; very small values may use scientific notation.

Line · Input · Result · Error

Using this with a spreadsheet

Copy one numeric column without its header and paste it here.

Choose the units and decimal separator, then convert. Use the line numbers to find errors.

When all rows are valid, copy the results column beside your original data. Download CSV if you need the full record.

Prefer a formula in Excel?

Use this formula when your source value is in A1, then fill down. Depending on your Excel settings, replace argument commas with semicolons. Unit codes are case-sensitive.

=CONVERT(A1,"kg","lbm")

Example: convert a kg column to lb

Definitions and limits

1 lb = 0.45359237 kg and 1 in = 2.54 cm are exact definitions. Temperature conversion is for temperatures, not temperature differences. Results are rounded to your chosen precision. Inputs with absolute value above 10¹⁵, calculations outside the numeric range, and temperatures below absolute zero are rejected.

Convert a single value →

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Square meters, square feet and pyeong

1 m² ≈ 10.764 ft² and 1 ft² ≈ 0.0929 m². Listings in the US, Canada and India use square feet.

1 acre ≈ 4,046.86 m² ≈ 0.4047 ha, and 1 hectare ≈ 2.471 acres.

1 pyeong = 400/121 m² ≈ 3.3058 m². Koreans still describe homes in pyeong, and the Japanese tsubo is the same size.

Tatami mats (jō) describe room sizes in Japan. Mat sizes vary by region, and this converter uses the 1.62 m² minimum set for Japanese property listings.

1 mu (亩) ≈ 666.67 m², the Chinese farmland unit, with 15 mu to a hectare.

How many square meters is one pyeong?

One pyeong is 400/121 m², about 3.3058 m². One square meter is 0.3025 pyeong.

How many square feet is 100 m²?

About 1,076.39 ft².

US and UK units are not the same size

Gallons, quarts, pints and fluid ounces share names but differ between the US and the UK. A US gallon is about 3.785 L and an imperial gallon about 4.546 L. A UK pint (about 568 mL) is about 20% larger than a US pint (about 473 mL). Pick the US units for American products.

1 L = 1,000 mL = 1,000 cc

1 m³ = 1,000 L

A 12 fl oz can ≈ 355 mL

1 oil barrel = 42 US gallons ≈ 159 L

Speed units at a glance

1 mph = 1.609344 km/h, and 100 km/h ≈ 62.1 mph

1 m/s = 3.6 km/h. Wind speed is often given in m/s or knots.

1 knot = 1 nautical mile per hour = 1.852 km/h, used at sea and in the air.

Mach 1 depends on air temperature. This converter uses 340.294 m/s (about 1,225 km/h), the speed of sound at sea level and 15 °C.

Months and years are averages

Months run from 28 to 31 days and years have 365 or 366 days. This converter uses Gregorian averages: 1 year = 365.2425 days and 1 month = 1/12 of that, about 30.44 days.

1 day = 24 hours = 1,440 minutes = 86,400 seconds

1 week = 168 hours = 604,800 seconds

One million seconds ≈ 11.6 days and one billion seconds ≈ 31.7 years

Why a 1 TB drive shows 931 GB

Drive makers count in decimal, so 1 TB is 1,000,000,000,000 bytes. Windows divides by powers of 1,024 and still labels the result GB, so the same drive appears as about 931 GB. Nothing is missing; the two numbers use different units. To tell them apart, the IEC named the binary units KiB, MiB, GiB and TiB.

1 KB = 1,000 bytes, 1 KiB = 1,024 bytes

1 GB = 1,000 MB, 1 GiB = 1,024 MiB

1 byte = 8 bits

How many MB are in 1 GB?

1,000 MB in decimal units. In binary units, 1 GiB = 1,024 MiB.

My 1 TB drive shows 931 GB. Is it faulty?

No. 1 TB in decimal is about 931 GiB in binary units, and Windows labels that figure GB.

Why 100 Mbps means 12.5 MB/s

Internet plans are sold in bits per second, while file sizes and download managers use bytes. A byte has 8 bits, so divide Mbps by 8 to get MB/s.

100 Mbps = 12.5 MB/s

500 Mbps = 62.5 MB/s

1 Gbps = 125 MB/s

Real downloads are usually a little slower because of Wi-Fi conditions, the server and protocol overhead.

Reading tire pressure

The recommended pressure depends on the vehicle. It is printed on the sticker inside the driver's door and in the manual, usually in psi and kPa or bar. If the air pump at the station uses a different unit, convert it here.

1 bar = 100 kPa ≈ 14.5 psi

1 psi ≈ 6.895 kPa ≈ 0.0689 bar

1 atm = 101.325 kPa = 760 mmHg = 1,013.25 hPa

1 kgf/cm² ≈ 0.98 bar ≈ 14.22 psi

Food calories and kilojoules

The "Calories" on food labels are kilocalories (kcal). Since 1 kcal = 4.184 kJ, divide by 4.184 if a European or Australian label only lists kJ. This converter uses the thermochemical calorie of 4.184 J.

1 kWh = 3,600 kJ ≈ 860 kcal

1 BTU ≈ 1.055 kJ, used for heating and cooling capacity

1 Wh = 3,600 J

There are two kinds of horsepower

Car specs in Korea, Japan and Europe mostly quote metric horsepower (PS, about 735.5 W), while US specs use mechanical horsepower (hp, about 745.7 W). The same engine therefore shows a figure about 1.4% lower in hp. Electric cars and official European documents use kW.

1 kW ≈ 1.36 PS ≈ 1.34 hp

100 PS ≈ 73.5 kW

1 kW ≈ 3,412 BTU/h

Fuel economy units run in opposite directions

km/L and mpg measure distance per unit of fuel, so higher is better. Korea and Japan use km/L, the US and UK use mpg.

L/100 km measures fuel used per 100 km, so lower is better. Europe, China and Australia use it.

L/100 km is the inverse of the others, so there is no single multiplier. L/100 km = 100 ÷ km/L, and L/100 km ≈ 235.215 ÷ US mpg. UK mpg uses the larger imperial gallon, so the same car scores about 20% higher than in US mpg.

Degrees and radians

A full turn is 360° = 2π radians, so radians = degrees × π/180 and degrees = radians × 180/π. Trig functions in Excel, JavaScript and Python expect radians, so convert before you call them.

90° = π/2 ≈ 1.5708 rad

1° = 60′ (arcminutes) = 3,600″ (arcseconds)

100 gradians (gon) = 90°

1 ° = 0.01745329252 rad

Formula: rad = ° × 0.01745329252

Height (feet + inches ↔ cm)

· 0.002777777778 turn

Value · Equals · Unit

1 ° · 0.01745329 rad · radian

1 ° · 1.111111 gon · gradian (gon)

1 ° · 60 ′ · arcminute

1 ° · 3,600 ″ · arcsecond

1 ° · 0.002777778 turn · turn

Frequency units

Hertz (Hz) counts repetitions per second. A 144 Hz monitor redraws the screen 144 times a second, and a 3.5 GHz CPU ticks 3.5 billion times a second.

1 rpm = 1/60 Hz, so a motor at 3,000 rpm turns at 50 Hz.

1 Hz = 2π rad/s

FM radio is measured in MHz, and Wi-Fi uses the 2.4 GHz and 5 GHz bands.

A cup is not the same everywhere

Korean and Japanese recipes: 1 cup = 200 mL

US recipes: 1 cup ≈ 236.6 mL

Metric cup (Australia, New Zealand and others): 250 mL

Tablespoon 15 mL and teaspoon 5 mL. The US tablespoon is about 14.8 mL, practically the same.

Converting volume to weight

Pick an ingredient to turn cups or spoons into grams. Dry ingredients vary a lot depending on whether they are sifted or packed, so the values here are typical for spooned and levelled measures. For baking, a kitchen scale is the most reliable.

How many grams is a cup of flour?

About 125 g for a US cup (about 236.6 mL) of all-purpose flour, spooned and levelled. It varies with how you fill the cup.

How many mL are in a tablespoon?

A tablespoon is 15 mL (the US tablespoon is about 14.8 mL), and a teaspoon is 5 mL. One tablespoon equals three teaspoons.

About these units

troy ounce (oz t)

The troy ounce (oz t) is the unit for gold, silver and other precious metal prices, exactly 31.1034768 g and about 10% heavier than a regular ounce.

gram (g)

A gram (g) is one thousandth of a kilogram, the usual unit for recipe ingredients and nutrition labels.

1 oz t = 31.1034768 g

Formula: g = oz t × 31.1034768

Height (feet + inches ↔ cm)

1 oz t in other units

· 0.00003428571429 US ton

· 0.0000306122449 UK ton

How to convert troy ounces to grams

Start from the exact relation: 1 oz t = 31.1034768 g

Put your value into the formula: g = oz t × 31.10348

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1 × 31.10348 = 31.1 g

0.1 × 31.10348 = 3.11 g

Mental-math shortcut

Use oz t × 31. For 1 oz t that gives about 31 g instead of 31.1 g (0.33% too low).

Definition and source: 1 troy ounce = 31.1034768 g exactly (480 grains of 64.79891 mg). Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

50 oz t · 1,555.17 g

100 oz t · 3,110.35 g

More weight conversions

What is 1 troy ounce in grams?

1 troy ounce = 31.1 grams. Multiply the value in oz t by 31.10348.

What is 1 gram in troy ounces?

1 gram = 0.0322 troy ounces.

How do I convert troy ounces to grams in my head?

How many troy ounces are in a 1 kg bar?

1 kg = 32.15 troy oz. In ordinary ounces it would be 35.27 oz, so check that a price per ounce means troy ounces.

About these units

don / monme (3.75 g)

The don is a traditional Korean unit of 3.75 g, still used when buying and selling gold. It equals the Japanese monme (匁).

gram (g)

A gram (g) is one thousandth of a kilogram, the usual unit for recipe ingredients and nutrition labels.

1 don / monme = 3.75 g

Formula: g = don / monme × 3.75

Height (feet + inches ↔ cm)

1 don / monme in other units

· 0.0005905239166 st

· 0.000004133667416 US ton

· 0.000003690774479 UK ton

How to convert don to grams

Start from the exact relation: 1 don / monme = 3.75 g

Put your value into the formula: g = don / monme × 3.75

Round to the precision you need. The tables on this page show 2 to 3 decimals.

0.5 × 3.75 = 1.875 g

Mental-math shortcut

don / monme × 3.75 is exact, not an estimate. Example: 1 don / monme = 3.75 g.

Definition and source: 1 don = 3.75 g, the same as the Japanese monme (匁): Japan’s 1891 Weights and Measures Act set 1 kan = 3.75 kg (1 monme = 3.75 g). Korean jewelers still quote gold per don alongside grams. Source: 계량에 관한 법률 (Korea, Act on Measures) (checked 2026-10-12).

don / monme to g table

1 don / monme · 3.75 g

g to don / monme table

More weight conversions

What is 1 don / monme in grams?

1 don / monme = 3.75 grams. Multiply the value in don / monme by 3.75.

What is 1 gram in don?

1 gram = 0.267 don.

How do I convert don to grams in my head?

How many grams is a 1-don gold ring?

3.75 g of gold. 10 don = 37.5 g, and a 1 troy ounce gold coin is about 8.29 don.

About these units

geun / Taiwan catty (600 g)

The geun is a Korean market unit, usually 600 g for meat, though vegetables and fruit are sometimes counted at 375 g. The Taiwanese catty (台斤) is also 600 g.

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

What is 10 geun in kilograms?

10 geun = 6 kilograms. Multiply the value in geun / Taiwan catty by 0.6.

What is 1 kilogram in geun?

1 kilogram = 1.667 geun.

How do I convert geun to kilograms in my head?

geun / Taiwan catty × 0.6 is exact, not an estimate. Example: 10 geun = 6 kg.

Is a Korean geun the same as a Chinese jin?

No. The Korean and Taiwanese geun is 600 g, the mainland Chinese jin (斤) is 500 g and the Hong Kong catty is about 604.8 g.

About these units

jin (Chinese catty, 500 g)

The jin (斤) is the mainland Chinese catty, defined as 500 g. Market prices for vegetables and meat are usually quoted per jin.

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

Reverse conversion: Kilograms to Jin

Formula: kg = jin × 0.5

Height (feet + inches ↔ cm)

2 jin in other units

· 0.001102311311 US ton

· 0.0009842065276 UK ton

How to convert jin to kilograms

Start from the exact relation: 1 jin = 0.5 kg

Put your value into the formula: kg = jin ÷ 2

Round to the precision you need. The tables on this page show 2 to 3 decimals.

Mental-math shortcut

jin ÷ 2 is exact, not an estimate. Example: 100 jin = 50 kg.

Definition and source: 1 jin (市斤) = 0.5 kg = 500 g, and 1 kg = 2 jin. China’s State Council order of 25 June 1959 kept this market-system jin and changed it to 10 liang (1 liang = 50 g). Source: 国务院关于统一我国计量制度的命令 (1959-06-25), 国务院公报 1959年第16号 (checked 2026-10-12).

More weight conversions

What is 100 jin in kilograms?

100 jin = 50 kilograms. Multiply the value in jin by 0.5.

What is 57 kilograms in jin?

57 kilograms = 114 jin.

How do I convert jin to kilograms in my head?

How many grams is 1 liang (两)?

50 g. 1 jin = 10 liang = 500 g, so half a jin (半斤) is 250 g.

Is the Taiwan or Hong Kong jin also 500 g?

No. The Taiwanese catty (台斤) is 600 g and the Hong Kong catty about 604.8 g; only the mainland 市斤 is exactly 500 g.

About these units

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

jin (Chinese catty, 500 g)

The jin (斤) is the mainland Chinese catty, defined as 500 g. Market prices for vegetables and meat are usually quoted per jin.

Reverse conversion: Jin to Kilograms

Formula: jin = kg × 2

Height (feet + inches ↔ cm)

60 kg in other units

· 0.06613867866 US ton

· 0.05905239166 UK ton

How to convert kilograms to jin

Start from the exact relation: 1 kg = 2 jin

Put your value into the formula: jin = kg × 2

Round to the precision you need. The tables on this page show 2 to 3 decimals.

Mental-math shortcut

kg × 2 is exact, not an estimate. Example: 57 kg = 114 jin.

Definition and source: 1 jin (市斤) = 0.5 kg = 500 g, and 1 kg = 2 jin. China’s State Council order of 25 June 1959 kept this market-system jin and changed it to 10 liang (1 liang = 50 g). Source: 国务院关于统一我国计量制度的命令 (1959-06-25), 国务院公报 1959年第16号 (checked 2026-10-12).

More weight conversions

What is 57 kilograms in jin?

57 kilograms = 114 jin. Multiply the value in kg by 2.

What is 100 jin in kilograms?

100 jin = 50 kilograms.

How do I convert kilograms to jin in my head?

How do I give my body weight in jin?

Double the kilograms: 57 kg = 114 jin, 60 kg = 120 jin, 72 kg = 144 jin.

Is the Taiwan or Hong Kong jin also 500 g?

No. The Taiwanese catty (台斤) is 600 g and the Hong Kong catty about 604.8 g; only the mainland 市斤 is exactly 500 g.

About these units

stone (st)

The stone (st) is 14 pounds, about 6.35 kg, and is how body weight is commonly stated in the UK and Ireland.

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

Reverse conversion: Kilograms to Stone

12 st = 76.20351816 kg

= 168 lb 0 oz · 12 st 0 lb

Formula: kg = st × 6.35029318

Height (feet + inches ↔ cm)

12 st in other units

How to convert stone to kilograms

Start from the exact relation: 1 st = 6.35029318 kg

Put your value into the formula: kg = st × 6.350293

Round to the precision you need. The tables on this page show 2 to 3 decimals.

2 × 6.350293 = 12.7 kg

12 × 6.350293 = 76.2 kg

Mental-math shortcut

Use st × 6.35. For 2 st that gives about 12.7 kg instead of 12.7 kg (0.0046% too low).

Definition and source: 1 stone = 14 lb = 6.35029318 kg exactly (UK Weights and Measures Act 1985, with the 1959 pound of 0.45359237 kg). Source: UK Weights and Measures Act 1985, Schedule 1 (checked 2026-10-12).

Kilograms to Stone →

More weight conversions

Work out your BMI from height and weight →

What is 2 stone in kilograms?

2 stone = 12.7 kilograms. Multiply the value in st by 6.350293.

What is 70 kilograms in stone?

70 kilograms = 11.02 stone.

How do I convert stone to kilograms in my head?

How do I convert stone and pounds (e.g. 9 st 7 lb) to kg?

Turn it all into pounds first: 9 × 14 + 7 = 133 lb, then × 0.45359237 = 60.33 kg.

About these units

kilogram (kg)

The kilogram (kg) is the SI base unit of mass. Since 2019 it has been defined through the Planck constant.

stone (st)

The stone (st) is 14 pounds, about 6.35 kg, and is how body weight is commonly stated in the UK and Ireland.

Reverse conversion: Stone to Kilograms

70 kg = 11.02311311 st

= 154 lb 5.18 oz · 11 st 0.32 lb

Formula: st = kg × 0.1574730444

Height (feet + inches ↔ cm)

70 kg in other units

· 0.07716179176 US ton

· 0.06889445693 UK ton

How to convert kilograms to stone

Start from the exact relation: 1 kg = 0.1574730444 st

Put your value into the formula: st = kg × 0.157473

Round to the precision you need. The tables on this page show 2 to 3 decimals.

70 × 0.157473 = 11.02 st

40 × 0.157473 = 6.299 st

Mental-math shortcut

Use kg ÷ 6.35. For 70 kg that gives about 11.02 st instead of 11.02 st (0.0046% too high).

Definition and source: 1 stone = 14 lb = 6.35029318 kg exactly (UK Weights and Measures Act 1985, with the 1959 pound of 0.45359237 kg). Source: UK Weights and Measures Act 1985, Schedule 1 (checked 2026-10-12).

Stone to Kilograms →

More weight conversions

Work out your BMI from height and weight →

What is 70 kilograms in stone?

70 kilograms = 11.02 stone. Multiply the value in kg by 0.157473.

What is 2 stone in kilograms?

2 stone = 12.7 kilograms.

How do I convert kilograms to stone in my head?

How do I write kg as stone and pounds?

Divide kg by 6.35029 for stone, then multiply the decimal part by 14 for pounds: 70 kg = 11.02 st = 11 st 0.32 lb.

About these units

pyeong / tsubo

The pyeong is the area of a square 6 shaku (about 1.818 m) on each side, 400/121 m² or about 3.3058 m². Koreans still use it for homes and land, though official documents use square meters. The Japanese tsubo (坪) is the same size.

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

What is 30 pyeong in square meters?

30 pyeong = 99.17 square meters. Multiply the value in pyeong / tsubo by 3.305785.

What is 12 square meters in pyeong?

12 square meters = 3.63 pyeong.

How do I convert pyeong to square meters in my head?

Use pyeong / tsubo × 3.3. For 30 pyeong that gives about 99 m² instead of 99.17 m² (0.18% too low).

Why is an 84 m² Korean apartment called “34 pyeong”?

84 m² is the exclusive floor area (25.4 pyeong). “34 pyeong” refers to the supply area, which adds shared spaces such as stairs and corridors (about 110–115 m²).

About these units

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

pyeong / tsubo

The pyeong is the area of a square 6 shaku (about 1.818 m) on each side, 400/121 m² or about 3.3058 m². Koreans still use it for homes and land, though official documents use square meters. The Japanese tsubo (坪) is the same size.

What is 12 square meters in pyeong?

12 square meters = 3.63 pyeong. Multiply the value in m² by 0.3025.

What is 30 pyeong in square meters?

30 pyeong = 99.17 square meters.

How do I convert square meters to pyeong in my head?

m² × 0.3025 is exact, not an estimate. Example: 12 m² = 3.63 pyeong.

Is 1 pyeong exactly 3.3 m²?

Not exactly: 1 pyeong = 3.305785 m². Dividing by 3.3 gives a result about 0.2% too high; multiplying by 0.3025 is exact.

About these units

square foot (ft²)

A square foot (ft²) is a square 1 foot on each side, about 0.0929 m². Home sizes in the US, Canada and India are usually given in square feet.

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

What is 30,000 square feet in square meters?

30,000 square feet = 2,787.09 square meters. Multiply the value in ft² by 0.09290304.

What is 20 square meters in square feet?

20 square meters = 215.28 square feet.

How do I convert square feet to square meters in my head?

Use ft² ÷ 10.76. For 30,000 ft² that gives about 2,788.1 m² instead of 2,787.09 m² (0.036% too high).

How big is a 2,000 sq ft house in m²?

2,000 × 0.09290304 = 185.81 m².

About these units

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

square foot (ft²)

A square foot (ft²) is a square 1 foot on each side, about 0.0929 m². Home sizes in the US, Canada and India are usually given in square feet.

What is 20 square meters in square feet?

20 square meters = 215.28 square feet. Multiply the value in m² by 10.76391.

What is 30,000 square feet in square meters?

30,000 square feet = 2,787.09 square meters.

How do I convert square meters to square feet in my head?

Use m² × 10.76. For 20 m² that gives about 215.2 ft² instead of 215.28 ft² (0.036% too low).

Why isn’t 1 m² equal to 3.28 ft²?

3.28 is the length factor (1 m = 3.28 ft). Area needs it squared: 3.2808² = 10.764 ft² per m².

About these units

acre (ac)

The acre is a US and imperial unit of land area, about 4,046.86 m² or 0.4047 hectares.

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

1 ac = 4,046.856422 m²

Formula: m² = ac × 4,046.856422

Height (feet + inches ↔ cm)

· 0.004046856422 km²

How to convert acres to square meters

Start from the exact relation: 1 ac = 4,046.856422 m²

Put your value into the formula: m² = ac × 4,046.856

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1.03 × 4,046.856 = 4,168.26 m²

0.1 × 4,046.856 = 404.69 m²

Mental-math shortcut

Use ac × 4,047. For 1.03 ac that gives about 4,168.41 m² instead of 4,168.26 m² (0.0035% too high).

Definition and source: 1 international acre = 4,046.8564224 m² exactly (43,560 ft²); 1 hectare = 10,000 m² = 2.4711 acres. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

0.25 ac · 1,011.71 m²

0.5 ac · 2,023.43 m²

1.03 ac · 4,168.26 m²

10 ac · 40,468.56 m²

20 ac · 80,937.13 m²

50 ac · 202,342.82 m²

100 ac · 404,685.64 m²

More area conversions

What is 1.03 acres in square meters?

1.03 acres = 4,168.26 square meters. Multiply the value in ac by 4,046.856.

What is 1 square meter in acres?

1 square meter = 0.000247 acres.

How do I convert acres to square meters in my head?

How does an acre compare with a football pitch?

A 105 × 68 m pitch is 7,140 m², about 1.76 acres, so one acre is roughly 57% of a pitch.

About these units

hectare (ha)

A hectare (ha) is a 100 m by 100 m square, 10,000 m², used for farmland and forests.

acre (ac)

The acre is a US and imperial unit of land area, about 4,046.86 m² or 0.4047 hectares.

1 ha = 2.471053815 ac

Formula: ac = ha × 2.471053815

Height (feet + inches ↔ cm)

· 10,000,000,000 mm²

· 0.003861021585 mi²

How to convert hectares to acres

Start from the exact relation: 1 ha = 2.471053815 ac

Put your value into the formula: ac = ha × 2.471054

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1,100 × 2.471054 = 2,718.16 ac

1.62 × 2.471054 = 4.003 ac

Mental-math shortcut

Use ha × 2.5. For 1,100 ha that gives about 2,750 ac instead of 2,718.16 ac (1.2% too high).

Definition and source: 1 international acre = 4,046.8564224 m² exactly (43,560 ft²); 1 hectare = 10,000 m² = 2.4711 acres. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

1,000 ha · 2,471.05 ac

1,100 ha · 2,718.16 ac

More area conversions

What is 1,100 hectares in acres?

1,100 hectares = 2,718.16 acres. Multiply the value in ha by 2.471054.

What is 1 acre in hectares?

1 acre = 0.405 hectares.

How do I convert hectares to acres in my head?

Which is bigger, a hectare or an acre?

The hectare: 1 ha = 2.471 acres, and 1 acre = 0.4047 ha.

About these units

mu (Chinese acre)

The mu (亩) is a Chinese unit for farmland, 1/15 of a hectare or about 666.67 m².

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

1 mu = 666.6666667 m²

Formula: m² = mu × 666.6666667

Height (feet + inches ↔ cm)

· 0.0006666666667 km²

· 0.000257401439 mi²

How to convert mu to square meters

Start from the exact relation: 1 mu = 666.6666667 m²

Put your value into the formula: m² = mu × 666.6667

Round to the precision you need. The tables on this page show 2 to 3 decimals.

1 × 666.6667 = 666.67 m²

0.1 × 666.6667 = 66.67 m²

Mental-math shortcut

Use mu × 667. For 1 mu that gives about 667 m² instead of 666.67 m² (0.05% too high).

Definition and source: 1 mu (市亩) = 10,000/15 m² ≈ 666.67 m², so 15 mu = 1 hectare. It belongs to the market system (市制) that China’s 1959 measurement order kept, and it is still used for farmland. Source: 国务院关于统一我国计量制度的命令 (1959-06-25), 国务院公报 1959年第16号 (checked 2026-10-12).

20 mu · 13,333.33 m²

50 mu · 33,333.33 m²

100 mu · 66,666.67 m²

More area conversions

What is 1 mu in square meters?

1 mu = 666.67 square meters. Multiply the value in mu by 666.6667.

What is 1 square meter in mu?

1 square meter = 0.0015 mu.

How do I convert mu to square meters in my head?

How many mu are in an acre?

1 acre = 6.07 mu, and 1 mu = 0.1647 acre.

About these units

jō (tatami mat, 1.62 m²)

The jō (畳) counts tatami mats and is how room sizes are given in Japan. Mat sizes vary by region, so Japanese property listings count one jō as at least 1.62 m². This converter uses 1.62 m².

square meter (m²)

A square meter (m²) is the area of a square 1 m on each side. It is the legal unit for floor area in most countries.

What is 6 jō in square meters?

6 jō = 9.72 square meters. Multiply the value in jō by 1.62.

What is 1 square meter in jō?

1 square meter = 0.617 jō.

How do I convert jō to square meters in my head?

jō × 1.62 is exact, not an estimate. Example: 6 jō = 9.72 m².

How big is a 6-jō room?

About 9.72 m² at 1.62 m² per jō, or 2.94 tsubo (2 jō ≈ 1 tsubo).

About these units

liter (L)

A liter (L) is the volume of a 10 cm cube, 1,000 mL.

US gallon (gal)

The US gallon is about 3.785 L, used for fuel prices and milk in the US. The UK (imperial) gallon is larger, about 4.546 L.

Reverse conversion: US Gallons to Liters

50 L = 13.20860262 gal

Formula: gal = L × 0.2641720524

Height (feet + inches ↔ cm)

· 1,690.701135 fl oz

· 10.99846241 UK gal

· 1,759.753986 UK fl oz

How to convert liters to US gallons

Start from the exact relation: 1 L = 0.2641720524 gal

Put your value into the formula: gal = L × 0.2641721

Round to the precision you need. The tables on this page show 2 to 3 decimals.

20 × 0.2641721 = 5.283 gal

50 × 0.2641721 = 13.21 gal

Mental-math shortcut

Use L ÷ 3.8. For 20 L that gives about 5.263 gal instead of 5.283 gal (0.38% too low).

Definition and source: 1 US gallon = 231 in³ = 3.785411784 L exactly. The UK (imperial) gallon is 4.54609 L, about 20% larger. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; UK Weights and Measures Act 1985, Schedule 1 (checked 2026-10-12).

1,000 L · 264.17 gal

US Gallons to Liters →

More volume conversions

What is 20 liters in US gallons?

20 liters = 5.283 US gallons. Multiply the value in L by 0.2641721.

What is 32 US gallons in liters?

32 US gallons = 121.13 liters.

How do I convert liters to US gallons in my head?

How many liters is a UK gallon?

4.54609 L. 10 L = 2.64 US gal but only 2.20 UK gal.

About these units

US gallon (gal)

The US gallon is about 3.785 L, used for fuel prices and milk in the US. The UK (imperial) gallon is larger, about 4.546 L.

liter (L)

A liter (L) is the volume of a 10 cm cube, 1,000 mL.

Reverse conversion: Liters to US Gallons

10 gal = 37.85411784 L

Formula: L = gal × 3.785411784

Height (feet + inches ↔ cm)

10 gal in other units

· 8.326741846 UK gal

· 1,332.278695 UK fl oz

How to convert US gallons to liters

Start from the exact relation: 1 gal = 3.785411784 L

Put your value into the formula: L = gal × 3.785412

Round to the precision you need. The tables on this page show 2 to 3 decimals.

32 × 3.785412 = 121.13 L

10 × 3.785412 = 37.85 L

Mental-math shortcut

Use gal × 3.8. For 32 gal that gives about 121.6 L instead of 121.13 L (0.39% too high).

Definition and source: 1 US gallon = 231 in³ = 3.785411784 L exactly. The UK (imperial) gallon is 4.54609 L, about 20% larger. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; UK Weights and Measures Act 1985, Schedule 1 (checked 2026-10-12).

2,000 gal · 7,570.82 L

Liters to US Gallons →

More volume conversions

What is 32 US gallons in liters?

32 US gallons = 121.13 liters. Multiply the value in gal by 3.785412.

What is 20 liters in US gallons?

20 liters = 5.283 US gallons.

How do I convert US gallons to liters in my head?

How many liters is a 15-gallon fuel tank?

56.78 L in US gallons, or 68.19 L if they are UK gallons.

About these units

milliliter (mL)

A milliliter (mL) is one thousandth of a liter and equals one cubic centimeter (cc).

US fluid ounce (fl oz)

The US fluid ounce (fl oz) is about 29.57 mL and appears on drink cans and cosmetics. It measures volume, unlike the ounce (oz) of weight.

Reverse conversion: US Fluid Ounces to Milliliters

500 mL = 16.90701135 fl oz

Formula: fl oz = mL × 0.0338140227

Height (feet + inches ↔ cm)

500 mL in other units

· 0.1099846241 UK gal

· 0.4399384966 UK qt

· 0.8798769932 UK pt

· 17.59753986 UK fl oz

· 0.003144905385 bbl

How to convert milliliters to US fluid ounces

Start from the exact relation: 1 mL = 0.0338140227 fl oz

Put your value into the formula: fl oz = mL × 0.03381402

Round to the precision you need. The tables on this page show 2 to 3 decimals.

55 × 0.03381402 = 1.86 fl oz

500 × 0.03381402 = 16.91 fl oz

Mental-math shortcut

Use mL ÷ 30. For 55 mL that gives about 1.833 fl oz instead of 1.86 fl oz (1.4% too low).

Definition and source: 1 US fluid ounce = 1/128 US gallon = 29.5735295625 mL exactly. The UK fluid ounce is 28.4130625 mL, and US nutrition labels round 1 fl oz to 30 mL. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; US 21 CFR 101.9(b)(5)(viii), household measures on nutrition labels (checked 2026-10-12).

0.75 mL · 0.0254 fl oz

7.5 mL · 0.254 fl oz

100 mL · 3.381 fl oz

125 mL · 4.227 fl oz

150 mL · 5.072 fl oz

200 mL · 6.763 fl oz

250 mL · 8.454 fl oz

300 mL · 10.14 fl oz

330 mL · 11.16 fl oz

350 mL · 11.83 fl oz

473 mL · 15.99 fl oz

500 mL · 16.91 fl oz

750 mL · 25.36 fl oz

1,000 mL · 33.81 fl oz

0.5 fl oz · 14.79 mL

10 fl oz · 295.74 mL

12 fl oz · 354.88 mL

16 fl oz · 473.18 mL

20 fl oz · 591.47 mL

24 fl oz · 709.76 mL

32 fl oz · 946.35 mL

US Fluid Ounces to Milliliters →

More volume conversions

What is 55 milliliters in US fluid ounces?

55 milliliters = 1.86 US fluid ounces. Multiply the value in mL by 0.03381402.

What is 8.5 US fluid ounces in milliliters?

8.5 US fluid ounces = 251.38 milliliters.

How do I convert milliliters to US fluid ounces in my head?

Is a fluid ounce the same as an ounce of weight?

No. Fluid ounces measure volume; ounces measure weight. 1 fl oz of water weighs about 29.6 g, a little more than 1 oz (28.35 g).

About these units

US fluid ounce (fl oz)

The US fluid ounce (fl oz) is about 29.57 mL and appears on drink cans and cosmetics. It measures volume, unlike the ounce (oz) of weight.

milliliter (mL)

A milliliter (mL) is one thousandth of a liter and equals one cubic centimeter (cc).

Reverse conversion: Milliliters to US Fluid Ounces

12 fl oz = 354.8823547 mL

Formula: mL = fl oz × 29.57352956

Height (feet + inches ↔ cm)

12 fl oz in other units

· 0.0003548823548 m³

· 0.07806320481 UK gal

· 0.3122528192 UK qt

· 0.6245056385 UK pt

· 12.49011277 UK fl oz

· 0.002232142857 bbl

How to convert US fluid ounces to milliliters

Start from the exact relation: 1 fl oz = 29.57352956 mL

Put your value into the formula: mL = fl oz × 29.57353

Round to the precision you need. The tables on this page show 2 to 3 decimals.

8.5 × 29.57353 = 251.38 mL

12 × 29.57353 = 354.88 mL

Mental-math shortcut

Use fl oz × 30. For 8.5 fl oz that gives about 255 mL instead of 251.38 mL (1.4% too high).

Definition and source: 1 US fluid ounce = 1/128 US gallon = 29.5735295625 mL exactly. The UK fluid ounce is 28.4130625 mL, and US nutrition labels round 1 fl oz to 30 mL. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; US 21 CFR 101.9(b)(5)(viii), household measures on nutrition labels (checked 2026-10-12).

0.23 fl oz · 6.802 mL

0.5 fl oz · 14.79 mL

1.7 fl oz · 50.28 mL

2.7 fl oz · 79.85 mL

3.3 fl oz · 97.59 mL

3.4 fl oz · 100.55 mL

8.5 fl oz · 251.38 mL

10 fl oz · 295.74 mL

12 fl oz · 354.88 mL

16 fl oz · 473.18 mL

20 fl oz · 591.47 mL

24 fl oz · 709.76 mL

32 fl oz · 946.35 mL

64 fl oz · 1,892.71 mL

100 mL · 3.381 fl oz

150 mL · 5.072 fl oz

200 mL · 6.763 fl oz

250 mL · 8.454 fl oz

300 mL · 10.14 fl oz

330 mL · 11.16 fl oz

350 mL · 11.83 fl oz

Milliliters to US Fluid Ounces →

More volume conversions

What is 8.5 US fluid ounces in milliliters?

8.5 US fluid ounces = 251.38 milliliters. Multiply the value in fl oz by 29.57353.

What is 55 milliliters in US fluid ounces?

55 milliliters = 1.86 US fluid ounces.

How do I convert US fluid ounces to milliliters in my head?

How many mL is a 12 oz can?

A 12 fl oz US can holds 354.9 mL, which is why cans are labeled 355 mL.

About these units

US cup (cup)

The US cup is about 236.6 mL and is used in American recipes. Korean and Japanese recipes usually mean 200 mL, and the metric cup is 250 mL.

milliliter (mL)

A milliliter (mL) is one thousandth of a liter and equals one cubic centimeter (cc).

1 cup = 236.5882365 mL

Formula: mL = cup × 236.5882365

Height (feet + inches ↔ cm)

1 cup in other units

· 0.0002365882365 m³

· 0.05204213654 UK gal

· 0.2081685462 UK qt

· 0.4163370923 UK pt

· 8.326741846 UK fl oz

· 0.001488095238 bbl

How to convert US cups to milliliters

Start from the exact relation: 1 cup = 236.5882365 mL

Put your value into the formula: mL = cup × 236.5882

Round to the precision you need. The tables on this page show 2 to 3 decimals.

2 × 236.5882 = 473.18 mL

5 × 236.5882 = 1,182.94 mL

Mental-math shortcut

Use cup × 240. For 2 cup that gives about 480 mL instead of 473.18 mL (1.4% too high).

Definition and source: 1 US customary cup = 8 US fl oz = 236.5882365 mL. US nutrition labels use a 240 mL cup, a metric cup is 250 mL, and Korean and Japanese recipes use 200 mL. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; US 21 CFR 101.9(b)(5)(viii), household measures on nutrition labels (checked 2026-10-12).

0.125 cup · 29.57 mL

0.3333 cup · 78.86 mL

0.6667 cup · 157.73 mL

0.75 cup · 177.44 mL

More volume conversions

What is 2 US cups in milliliters?

2 US cups = 473.18 milliliters. Multiply the value in cup by 236.5882.

What is 1 milliliter in US cups?

1 milliliter = 0.00423 US cups.

How do I convert US cups to milliliters in my head?

How many grams is a cup?

A cup measures volume, so it depends on the ingredient: a US cup of water weighs about 237 g. For flour or sugar, pick the ingredient in the cooking converter.

About these units

US tablespoon (tbsp)

The US tablespoon is about 14.79 mL. Recipes from Korea, Japan and Europe use 15 mL, which is practically the same.

milliliter (mL)

A milliliter (mL) is one thousandth of a liter and equals one cubic centimeter (cc).

2 tbsp = 29.57352956 mL

Formula: mL = tbsp × 14.78676478

Height (feet + inches ↔ cm)

2 tbsp in other units

· 0.00002957352956 m³

· 0.006505267067 UK gal

· 0.02602106827 UK qt

· 0.05204213654 UK pt

· 1.040842731 UK fl oz

· 0.0001860119048 bbl

How to convert US tablespoons to milliliters

Start from the exact relation: 1 tbsp = 14.78676478 mL

Put your value into the formula: mL = tbsp × 14.78676

Round to the precision you need. The tables on this page show 2 to 3 decimals.

2 × 14.78676 = 29.57 mL

0.5 × 14.78676 = 7.393 mL

Mental-math shortcut

Use tbsp × 15. For 2 tbsp that gives about 30 mL instead of 29.57 mL (1.4% too high).

Definition and source: 1 US tablespoon = 1/2 US fl oz = 14.78676478125 mL. Metric, Korean and Japanese tablespoons are 15 mL, and US nutrition labels also use 15 mL. The Australian tablespoon is 20 mL. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B; US 21 CFR 101.9(b)(5)(viii), household measures on nutrition labels (checked 2026-10-12).

More volume conversions

What is 2 US tablespoons in milliliters?

2 US tablespoons = 29.57 milliliters. Multiply the value in tbsp by 14.78676.

What is 1 milliliter in US tablespoons?

1 milliliter = 0.0676 US tablespoons.

How do I convert US tablespoons to milliliters in my head?

How many teaspoons are in a tablespoon?

Three. A US teaspoon is 4.93 mL; a metric teaspoon is 5 mL.

About these units

kilometer per hour (km/h)

Kilometers per hour (km/h) is the speed unit on road signs and speedometers in most countries.

mile per hour (mph)

Miles per hour (mph) is the road speed unit in the US and UK. 1 mph is about 1.609 km/h.

Reverse conversion: Miles per Hour to Kilometers per Hour

100 km/h = 62.13711922 mph

Formula: mph = km/h ÷ 1.609344

Height (feet + inches ↔ cm)

100 km/h in other units

· 0.08162876153 Mach

How to convert kilometers per hour to miles per hour

Start from the exact relation: 1 km/h = 0.6213711922 mph

Put your value into the formula: mph = km/h ÷ 1.609344

Round to the precision you need. The tables on this page show 2 to 3 decimals.

300 ÷ 1.609344 = 186.41 mph

100 ÷ 1.609344 = 62.14 mph

Mental-math shortcut

Use km/h ÷ 1.6. For 300 km/h that gives about 187.5 mph instead of 186.41 mph (0.58% too high).

Definition and source: 1 mph = 1.609344 km/h exactly, because the international mile is 1,609.344 m; 1 km/h = 0.621371 mph. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

100 km/h · 62.14 mph

110 km/h · 68.35 mph

115 km/h · 71.46 mph

120 km/h · 74.56 mph

130 km/h · 80.78 mph

135 km/h · 83.89 mph

140 km/h · 86.99 mph

150 km/h · 93.21 mph

156 km/h · 96.93 mph

165 km/h · 102.53 mph

200 km/h · 124.27 mph

250 km/h · 155.34 mph

300 km/h · 186.41 mph

417 km/h · 259.11 mph

Miles per Hour to Kilometers per Hour →

More speed conversions

What is 300 kilometers per hour in miles per hour?

300 kilometers per hour = 186.41 miles per hour. Multiply the value in km/h by 0.6213712.

What is 55 miles per hour in kilometers per hour?

55 miles per hour = 88.51 kilometers per hour.

How do I convert kilometers per hour to miles per hour in my head?

What are common speed limits in both units?

UK motorways: 70 mph = 112.7 km/h; many US highways: 65 mph = 104.6 km/h; a 50 km/h town limit = 31.1 mph.

About these units

mile per hour (mph)

Miles per hour (mph) is the road speed unit in the US and UK. 1 mph is about 1.609 km/h.

kilometer per hour (km/h)

Kilometers per hour (km/h) is the speed unit on road signs and speedometers in most countries.

Reverse conversion: Kilometers per Hour to Miles per Hour

70 mph = 112.65408 km/h

Formula: km/h = mph × 1.609344

Height (feet + inches ↔ cm)

70 mph in other units

· 0.09195813032 Mach

How to convert miles per hour to kilometers per hour

Start from the exact relation: 1 mph = 1.609344 km/h

Put your value into the formula: km/h = mph × 1.609344

Round to the precision you need. The tables on this page show 2 to 3 decimals.

55 × 1.609344 = 88.51 km/h

70 × 1.609344 = 112.65 km/h

Mental-math shortcut

Use mph × 1.6. For 55 mph that gives about 88 km/h instead of 88.51 km/h (0.58% too low).

Definition and source: 1 mph = 1.609344 km/h exactly, because the international mile is 1,609.344 m; 1 km/h = 0.621371 mph. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

65 mph · 104.61 km/h

70 mph · 112.65 km/h

80 mph · 128.75 km/h

90 mph · 144.84 km/h

100 mph · 160.93 km/h

120 mph · 193.12 km/h

150 mph · 241.4 km/h

100 km/h · 62.14 mph

110 km/h · 68.35 mph

120 km/h · 74.56 mph

Kilometers per Hour to Miles per Hour →

More speed conversions

What is 55 miles per hour in kilometers per hour?

55 miles per hour = 88.51 kilometers per hour. Multiply the value in mph by 1.609344.

What is 300 kilometers per hour in miles per hour?

300 kilometers per hour = 186.41 miles per hour.

How do I convert miles per hour to kilometers per hour in my head?

Is mph the same as knots?

No: 1 knot = 1.1508 mph = 1.852 km/h.

About these units

knot (kn)

A knot (kn) is one nautical mile (1,852 m) per hour, used at sea, in aviation and for wind speed.

kilometer per hour (km/h)

Kilometers per hour (km/h) is the speed unit on road signs and speedometers in most countries.

Formula: km/h = kn × 1.852

Height (feet + inches ↔ cm)

20 kn in other units

· 0.03023529327 Mach

How to convert knots to kilometers per hour

Start from the exact relation: 1 kn = 1.852 km/h

Put your value into the formula: km/h = kn × 1.852

Round to the precision you need. The tables on this page show 2 to 3 decimals.

30 × 1.852 = 55.56 km/h

20 × 1.852 = 37.04 km/h

Mental-math shortcut

Use kn × 1.85. For 30 kn that gives about 55.5 km/h instead of 55.56 km/h (0.11% too low).

Definition and source: 1 knot = 1 nautical mile per hour = 1,852 m/h = 1.852 km/h exactly (≈1.1508 mph). The 1,852 m nautical mile was adopted internationally in 1929. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

160 kn · 296.32 km/h

600 kn · 1,111.2 km/h

More speed conversions

What is 30 knots in kilometers per hour?

30 knots = 55.56 kilometers per hour. Multiply the value in kn by 1.852.

What is 1 kilometer per hour in knots?

1 kilometer per hour = 0.54 knots.

How do I convert knots to kilometers per hour in my head?

Why do ships and aircraft use knots?

A nautical mile is about one minute of latitude, so knots fit navigation on charts marked in degrees and minutes.

About these units

knot (kn)

A knot (kn) is one nautical mile (1,852 m) per hour, used at sea, in aviation and for wind speed.

mile per hour (mph)

Miles per hour (mph) is the road speed unit in the US and UK. 1 mph is about 1.609 km/h.

20 kn = 23.01558896 mph

Formula: mph = kn × 1.150779448

Height (feet + inches ↔ cm)

20 kn in other units

· 0.03023529327 Mach

How to convert knots to miles per hour

Start from the exact relation: 1 kn = 1.150779448 mph

Put your value into the formula: mph = kn × 1.150779

Round to the precision you need. The tables on this page show 2 to 3 decimals.

52 × 1.150779 = 59.84 mph

20 × 1.150779 = 23.02 mph

Mental-math shortcut

Use kn × 1.15. For 52 kn that gives about 59.8 mph instead of 59.84 mph (0.068% too low).

Definition and source: 1 knot = 1 nautical mile per hour = 1,852 m/h = 1.852 km/h exactly (≈1.1508 mph). The 1,852 m nautical mile was adopted internationally in 1929. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

More speed conversions

What is 52 knots in miles per hour?

52 knots = 59.84 miles per hour. Multiply the value in kn by 1.150779.

What is 1 mile per hour in knots?

1 mile per hour = 0.869 knots.

How do I convert knots to miles per hour in my head?

How strong is a 34-knot wind?

34 kn = 39.1 mph = 63 km/h, the lower limit of force 8 (gale) on the Beaufort scale.

About these units

megabyte (MB)

A megabyte (MB) is 1,000,000 bytes. Some operating systems show mebibytes (1,048,576 bytes) labeled MB, so the same file can appear with slightly different sizes.

gigabyte (GB)

A gigabyte (GB) is one billion bytes. Drive makers use decimal GB while Windows shows binary values (GiB) labeled GB, which is why a 1 TB drive shows about 931 GB.

What is 2,000 megabytes in gigabytes?

2,000 megabytes = 2 gigabytes. Multiply the value in MB by 0.001.

What is 2 gigabytes in megabytes?

2 gigabytes = 2,000 megabytes.

How do I convert megabytes to gigabytes in my head?

MB ÷ 1,000 is exact, not an estimate. Example: 2,000 MB = 2 GB.

Why does a 5,000 MB file show as 4.66 GB?

Because the system divides by 1,024³: 5,000,000,000 bytes = 4.66 GiB, displayed as “GB”.

About these units

gigabyte (GB)

A gigabyte (GB) is one billion bytes. Drive makers use decimal GB while Windows shows binary values (GiB) labeled GB, which is why a 1 TB drive shows about 931 GB.

megabyte (MB)

A megabyte (MB) is 1,000,000 bytes. Some operating systems show mebibytes (1,048,576 bytes) labeled MB, so the same file can appear with slightly different sizes.

What is 2 gigabytes in megabytes?

2 gigabytes = 2,000 megabytes. Multiply the value in GB by 1,000.

What is 2,000 megabytes in gigabytes?

2,000 megabytes = 2 gigabytes.

How do I convert gigabytes to megabytes in my head?

GB × 1,000 is exact, not an estimate. Example: 2 GB = 2,000 MB.

Is 1 GB 1,000 MB or 1,024 MB?

In SI units, 1,000 MB. Windows shows binary values (1 GiB = 1,024 MiB) with the label “GB”, which is where 1,024 comes from.

About these units

megabyte (MB)

A megabyte (MB) is 1,000,000 bytes. Some operating systems show mebibytes (1,048,576 bytes) labeled MB, so the same file can appear with slightly different sizes.

Formula: MB = kB × 0.001

Height (feet + inches ↔ cm)

500 kB in other units

· 0.0004656612873 GiB

· 4.54747351×10⁻⁷ TiB

How to convert kilobytes to megabytes

Start from the exact relation: 1 kB = 0.001 MB

Put your value into the formula: MB = kB ÷ 1,000

Round to the precision you need. The tables on this page show 2 to 3 decimals.

130 ÷ 1,000 = 0.13 MB

500 ÷ 1,000 = 0.5 MB

Mental-math shortcut

kB ÷ 1,000 is exact, not an estimate. Example: 130 kB = 0.13 MB.

Definition and source: SI prefixes are decimal: 1 kB = 1,000 B, 1 MB = 1,000 kB and 1 GB = 1,000 MB. The binary units (IEC 80000-13) are KiB = 1,024 B, MiB = 1,024 KiB and GiB = 1,024 MiB. Source: BIPM, The International System of Units (SI Brochure, 9th ed., 2019) (checked 2026-10-12).

More data size conversions

All data size units →

What is 130 kilobytes in megabytes?

130 kilobytes = 0.13 megabytes. Multiply the value in kB by 0.001.

What is 1 megabyte in kilobytes?

1 megabyte = 1,000 kilobytes.

How do I convert kilobytes to megabytes in my head?

Is 1 MB 1,000 KB or 1,024 KB?

Decimal: 1 MB = 1,000 kB. Binary: 1 MiB = 1,024 KiB. Programs that show binary values as KB and MB display 8,000 KB as 7.81 MB.

About these units

gigabyte (GB)

A gigabyte (GB) is one billion bytes. Drive makers use decimal GB while Windows shows binary values (GiB) labeled GB, which is why a 1 TB drive shows about 931 GB.

gibibyte (GiB)

A gibibyte (GiB) is 2³⁰ = 1,073,741,824 bytes. Memory sizes and some operating systems use it.

What is 30 gigabytes in gibibytes?

30 gigabytes = 27.94 gibibytes. Multiply the value in GB by 0.9313226.

What is 1 gibibyte in gigabytes?

1 gibibyte = 1.074 gigabytes.

How do I convert gigabytes to gibibytes in my head?

Use GB × 0.93. For 30 GB that gives about 27.9 GiB instead of 27.94 GiB (0.14% too low).

Why does a 1 TB drive show about 931 GB?

1 TB = 10¹² bytes = 931.3 GiB, and Windows shows GiB values with the label “GB”.

About these units

megabit per second (Mbps)

Megabits per second (Mbps) is the unit for internet and Wi-Fi speeds. A byte has 8 bits, so a 100 Mbps line can download at most 12.5 MB/s in theory.

megabyte per second (MB/s)

Megabytes per second (MB/s) is shown by download managers and storage benchmarks. 1 MB/s equals 8 Mbps.

What is 500 megabits per second in megabytes per second?

500 megabits per second = 62.5 megabytes per second. Multiply the value in Mbps by 0.125.

What is 1 megabyte per second in megabits per second?

1 megabyte per second = 8 megabits per second.

How do I convert megabits per second to megabytes per second in my head?

Mbps ÷ 8 is exact, not an estimate. Example: 500 Mbps = 62.5 MB/s.

Why doesn’t a 1 Gbps line download at 125 MB/s?

1,000 Mbps ÷ 8 = 125 MB/s is the theoretical maximum. Protocol overhead (TCP/IP, Wi-Fi) takes a few percent, and some apps show MiB/s (125 MB/s = 119.2 MiB/s).

About these units

psi (pound per square inch) (psi)

Pounds per square inch (psi) is a US pressure unit, about 6.895 kPa, commonly used for tire pressure.

bar (bar)

One bar is 100,000 Pa (100 kPa), close to atmospheric pressure at sea level. It is used for tire pressure in Europe, diving and espresso machines.

What is 35 psi in bar?

35 psi = 2.413 bar. Multiply the value in psi by 0.06894757.

What is 3 bar in psi?

3 bar = 43.51 psi.

How do I convert psi to bar in my head?

Use psi ÷ 14.5. For 35 psi that gives about 2.414 bar instead of 2.413 bar (0.026% too high).

Is a tyre pressure reading absolute pressure?

No, it is gauge pressure, measured above the surrounding air. 32 psi = 2.21 bar = 221 kPa above the roughly 1.01 bar of the atmosphere.

About these units

bar (bar)

One bar is 100,000 Pa (100 kPa), close to atmospheric pressure at sea level. It is used for tire pressure in Europe, diving and espresso machines.

psi (pound per square inch) (psi)

Pounds per square inch (psi) is a US pressure unit, about 6.895 kPa, commonly used for tire pressure.

What is 1.8 bar in psi?

1.8 bar = 26.11 psi. Multiply the value in bar by 14.50377.

What is 35 psi in bar?

35 psi = 2.413 bar.

How do I convert bar to psi in my head?

Use bar × 14.5. For 1.8 bar that gives about 26.1 psi instead of 26.11 psi (0.026% too low).

Is 1 bar the same as 1 atmosphere?

Close but not equal: 1 atm = 1.01325 bar = 14.696 psi, and 1 bar = 0.98692 atm.

About these units

psi (pound per square inch) (psi)

Pounds per square inch (psi) is a US pressure unit, about 6.895 kPa, commonly used for tire pressure.

kilopascal (kPa)

A kilopascal (kPa) is 1,000 pascals. Tire placards in many countries list the recommended pressure in kPa alongside psi.

Reverse conversion: Kilopascals to PSI

32 psi = 220.6322334 kPa

Formula: kPa = psi × 6.894757293

Height (feet + inches ↔ cm)

32 psi in other units

· 2.249822655 kgf/cm²

How to convert psi to kilopascals

Start from the exact relation: 1 psi = 6.894757293 kPa

Put your value into the formula: kPa = psi × 6.894757

Round to the precision you need. The tables on this page show 2 to 3 decimals.

30 × 6.894757 = 206.84 kPa

32 × 6.894757 = 220.63 kPa

Mental-math shortcut

Use psi × 6.9. For 30 psi that gives about 207 kPa instead of 206.84 kPa (0.076% too high).

Definition and source: 1 psi = 6,894.757 Pa = 6.894757 kPa (one pound-force per square inch); 1 bar = 100 kPa exactly, so 1 bar = 14.5038 psi. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

100 psi · 689.48 kPa

Kilopascals to PSI →

More pressure conversions

All pressure units →

What is 30 psi in kilopascals?

30 psi = 206.84 kilopascals. Multiply the value in psi by 6.894757.

What is 250 kilopascals in psi?

250 kilopascals = 36.26 psi.

How do I convert psi to kilopascals in my head?

What is 1 kgf/cm² in psi?

1 kgf/cm² = 98.0665 kPa = 14.223 psi = 0.981 bar. Older Japanese and Korean gauges use it.

About these units

kilopascal (kPa)

A kilopascal (kPa) is 1,000 pascals. Tire placards in many countries list the recommended pressure in kPa alongside psi.

psi (pound per square inch) (psi)

Pounds per square inch (psi) is a US pressure unit, about 6.895 kPa, commonly used for tire pressure.

Reverse conversion: PSI to Kilopascals

250 kPa = 36.25943443 psi

Formula: psi = kPa × 0.1450377377

Height (feet + inches ↔ cm)

250 kPa in other units

· 2.549290532 kgf/cm²

How to convert kilopascals to psi

Start from the exact relation: 1 kPa = 0.1450377377 psi

Put your value into the formula: psi = kPa × 0.1450377

Round to the precision you need. The tables on this page show 2 to 3 decimals.

250 × 0.1450377 = 36.26 psi

100 × 0.1450377 = 14.5 psi

Mental-math shortcut

Use kPa × 0.145. For 250 kPa that gives about 36.25 psi instead of 36.26 psi (0.026% too low).

Definition and source: 1 psi = 6,894.757 Pa = 6.894757 kPa (one pound-force per square inch); 1 bar = 100 kPa exactly, so 1 bar = 14.5038 psi. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

100 kPa · 14.5 psi · 1 bar

150 kPa · 21.76 psi · 1.5 bar

180 kPa · 26.11 psi · 1.8 bar

190 kPa · 27.56 psi · 1.9 bar

200 kPa · 29.01 psi · 2 bar

210 kPa · 30.46 psi · 2.1 bar

220 kPa · 31.91 psi · 2.2 bar

230 kPa · 33.36 psi · 2.3 bar

240 kPa · 34.81 psi · 2.4 bar

250 kPa · 36.26 psi · 2.5 bar

260 kPa · 37.71 psi · 2.6 bar

280 kPa · 40.61 psi · 2.8 bar

300 kPa · 43.51 psi · 3 bar

350 kPa · 50.76 psi · 3.5 bar

400 kPa · 58.02 psi · 4 bar

PSI to Kilopascals →

More pressure conversions

All pressure units →

What is 250 kilopascals in psi?

250 kilopascals = 36.26 psi. Multiply the value in kPa by 0.1450377.

What is 30 psi in kilopascals?

30 psi = 206.84 kilopascals.

How do I convert kilopascals to psi in my head?

What is 250 kPa in psi and bar?

250 kPa = 36.3 psi = 2.5 bar = 2.55 kgf/cm².

About these units

kilocalorie (kcal)

The kilocalorie (kcal) is the food energy unit, roughly the energy to warm 1 kg of water by 1 °C. Food "Calories" are kilocalories. 1 kcal = 4.184 kJ.

kilojoule (kJ)

The kilojoule (kJ) is the SI energy unit. Food labels in the EU and Australia show kJ alongside kcal.

What is 1,300 kilocalories in kilojoules?

1,300 kilocalories = 5,439.2 kilojoules. Multiply the value in kcal by 4.184.

What is 2,142 kilojoules in kilocalories?

2,142 kilojoules = 511.95 kilocalories.

How do I convert kilocalories to kilojoules in my head?

Use kcal × 4.2. For 1,300 kcal that gives about 5,460 kJ instead of 5,439.2 kJ (0.38% too high).

Is a food Calorie the same as a calorie?

A food Calorie (capital C) is a kilocalorie: 2,000 kcal = 8,368 kJ.

About these units

kilojoule (kJ)

The kilojoule (kJ) is the SI energy unit. Food labels in the EU and Australia show kJ alongside kcal.

kilocalorie (kcal)

The kilocalorie (kcal) is the food energy unit, roughly the energy to warm 1 kg of water by 1 °C. Food "Calories" are kilocalories. 1 kcal = 4.184 kJ.

What is 2,142 kilojoules in kilocalories?

2,142 kilojoules = 511.95 kilocalories. Multiply the value in kJ by 0.2390057.

What is 1,300 kilocalories in kilojoules?

1,300 kilocalories = 5,439.2 kilojoules.

How do I convert kilojoules to kilocalories in my head?

Use kJ ÷ 4.2. For 2,142 kJ that gives about 510 kcal instead of 511.95 kcal (0.38% too low).

How many kcal is the 8,700 kJ on Australian labels?

8,700 kJ (the average adult daily intake used on Australian labels) = 2,079 kcal.

About these units

horsepower (mechanical) (hp)

Mechanical horsepower (hp) is about 745.7 W and is how engine output is quoted in the US.

kilowatt (kW)

A kilowatt (kW) is 1,000 watts, used for electric motors, appliances and official engine ratings in Europe.

Reverse conversion: Kilowatts to Horsepower

300 hp = 223.7099615 kW

Formula: kW = hp × 0.7456998716

Height (feet + inches ↔ cm)

300 hp in other units

· 763,330.0733 BTU/h

· 192,484.6705 kcal/h

How to convert horsepower to kilowatts

Start from the exact relation: 1 hp = 0.7456998716 kW

Put your value into the formula: kW = hp × 0.7456999

Round to the precision you need. The tables on this page show 2 to 3 decimals.

300 × 0.7456999 = 223.71 kW

5 × 0.7456999 = 3.728 kW

Mental-math shortcut

Use hp × 0.75. For 300 hp that gives about 225 kW instead of 223.71 kW (0.58% too high).

Definition and source: Mechanical horsepower: 1 hp = 550 ft·lbf/s = 745.69987 W. Metric horsepower: 1 PS = 75 kgf·m/s = 735.49875 W. So 1 kW = 1.34102 hp = 1.35962 PS. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

1 hp · 0.746 kW · 1.014 PS

5 hp · 3.728 kW · 5.069 PS

10 hp · 7.457 kW · 10.14 PS

50 hp · 37.28 kW · 50.69 PS

100 hp · 74.57 kW · 101.39 PS

110 hp · 82.03 kW · 111.53 PS

120 hp · 89.48 kW · 121.66 PS

150 hp · 111.85 kW · 152.08 PS

170 hp · 126.77 kW · 172.36 PS

200 hp · 149.14 kW · 202.77 PS

250 hp · 186.42 kW · 253.47 PS

300 hp · 223.71 kW · 304.16 PS

400 hp · 298.28 kW · 405.55 PS

500 hp · 372.85 kW · 506.93 PS

1,000 hp · 745.7 kW · 1,013.87 PS

Kilowatts to Horsepower →

More power conversions

What is 300 horsepower in kilowatts?

300 horsepower = 223.71 kilowatts. Multiply the value in hp by 0.7456999.

What is 150 kilowatts in horsepower?

150 kilowatts = 201.15 horsepower.

How do I convert horsepower to kilowatts in my head?

How different are hp and PS?

1 hp is about 1.4% larger than 1 PS: 100 hp = 101.4 PS = 74.57 kW, and 100 PS = 98.6 hp = 73.55 kW.

About these units

kilowatt (kW)

A kilowatt (kW) is 1,000 watts, used for electric motors, appliances and official engine ratings in Europe.

horsepower (mechanical) (hp)

Mechanical horsepower (hp) is about 745.7 W and is how engine output is quoted in the US.

Reverse conversion: Horsepower to Kilowatts

150 kW = 201.1533134 hp

Formula: hp = kW × 1.34102209

Height (feet + inches ↔ cm)

150 kW in other units

· 129,063.0975 kcal/h

How to convert kilowatts to horsepower

Start from the exact relation: 1 kW = 1.34102209 hp

Put your value into the formula: hp = kW × 1.341022

Round to the precision you need. The tables on this page show 2 to 3 decimals.

300 × 1.341022 = 402.31 hp

150 × 1.341022 = 201.15 hp

Mental-math shortcut

Use kW × 1.34. For 300 kW that gives about 402 hp instead of 402.31 hp (0.076% too low).

Definition and source: Mechanical horsepower: 1 hp = 550 ft·lbf/s = 745.69987 W. Metric horsepower: 1 PS = 75 kgf·m/s = 735.49875 W. So 1 kW = 1.34102 hp = 1.35962 PS. Source: NIST SP 811 (2008), Guide for the Use of the SI, Appendix B (checked 2026-10-12).

0.6 kW · 0.805 hp · 0.816 PS

1 kW · 1.341 hp · 1.36 PS

5 kW · 6.705 hp · 6.798 PS

10 kW · 13.41 hp · 13.6 PS

50 kW · 67.05 hp · 67.98 PS

55 kW · 73.76 hp · 74.78 PS

60 kW · 80.46 hp · 81.58 PS

75 kW · 100.58 hp · 101.97 PS

96 kW · 128.74 hp · 130.52 PS

100 kW · 134.1 hp · 135.96 PS

110 kW · 147.51 hp · 149.56 PS

125 kW · 167.63 hp · 169.95 PS

150 kW · 201.15 hp · 203.94 PS

155 kW · 207.86 hp · 210.74 PS

200 kW · 268.2 hp · 271.92 PS

209 kW · 280.27 hp · 284.16 PS

210 kW · 281.61 hp · 285.52 PS

213 kW · 285.64 hp · 289.6 PS

250 kW · 335.26 hp · 339.91 PS

300 kW · 402.31 hp · 407.89 PS

500 kW · 670.51 hp · 679.81 PS

557 kW · 746.95 hp · 757.31 PS

Horsepower to Kilowatts →

More power conversions

What is 300 kilowatts in horsepower?

300 kilowatts = 402.31 horsepower. Multiply the value in kW by 1.341022.

What is 300 horsepower in kilowatts?

300 horsepower = 223.71 kilowatts.

How do I convert kilowatts to horsepower in my head?

Which horsepower do car spec sheets use?

European, Japanese and Korean spec sheets usually give PS (metric horsepower); US sheets use hp. 150 kW = 203.9 PS = 201.2 hp.

About these units

metric horsepower (PS) (PS)

Metric horsepower (PS) is about 735.5 W, roughly 1.4% less than mechanical horsepower. Car specs in Korea, Japan and Europe usually quote PS.

kilowatt (kW)

A kilowatt (kW) is 1,000 watts, used for electric motors, appliances and official engine ratings in Europe.

What is 140 metric horsepower in kilowatts?

140 metric horsepower = 102.97 kilowatts. Multiply the value in PS by 0.7354988.

What is 100 kilowatts in metric horsepower?

100 kilowatts = 135.96 metric horsepower.

How do I convert metric horsepower to kilowatts in my head?

Use PS × 0.735. For 140 PS that gives about 102.9 kW instead of 102.97 kW (0.068% too low).

How different are hp and PS?

1 hp is about 1.4% larger than 1 PS: 100 hp = 101.4 PS = 74.57 kW, and 100 PS = 98.6 hp = 73.55 kW.

About these units

kilowatt (kW)

A kilowatt (kW) is 1,000 watts, used for electric motors, appliances and official engine ratings in Europe.

metric horsepower (PS) (PS)

Metric horsepower (PS) is about 735.5 W, roughly 1.4% less than mechanical horsepower. Car specs in Korea, Japan and Europe usually quote PS.

What is 5 kilowatts in metric horsepower?

5 kilowatts = 6.798 metric horsepower. Multiply the value in kW by 1.359622.

What is 140 metric horsepower in kilowatts?

140 metric horsepower = 102.97 kilowatts.

How do I convert kilowatts to metric horsepower in my head?

Use kW × 1.36. For 5 kW that gives about 6.8 PS instead of 6.798 PS (0.028% too high).

Which horsepower do car spec sheets use?

European, Japanese and Korean spec sheets usually give PS (metric horsepower); US sheets use hp. 150 kW = 203.9 PS = 201.2 hp.

About these units

liter per 100 km (L/100 km)

Liters per 100 km measures how much fuel it takes to drive 100 km. Lower is better. It is the standard in Europe, China and Australia.

miles per gallon (US) (mpg)

Miles per gallon (mpg) is the distance in miles per US gallon. Higher is better. UK mpg uses the larger imperial gallon, so its figures are about 20% higher.

What is 7.2 liters per 100 km in miles per gallon?

7.2 liters per 100 km = 32.67 miles per gallon. Calculated with the formula above.

What is 17 miles per gallon in liters per 100 km?

17 miles per gallon = 13.84 liters per 100 km.

How do I convert liters per 100 km to miles per gallon in my head?

Use 235 ÷ L/100 km. For 7.2 L/100 km that gives about 32.64 mpg instead of 32.67 mpg (0.091% too low).

Why are UK mpg figures different?

UK mpg uses the 4.546 L gallon, so the same car shows about 20% more: 6 L/100 km = 39.2 mpg (US) = 47.1 mpg (UK).

About these units

miles per gallon (US) (mpg)

Miles per gallon (mpg) is the distance in miles per US gallon. Higher is better. UK mpg uses the larger imperial gallon, so its figures are about 20% higher.

liter per 100 km (L/100 km)

Liters per 100 km measures how much fuel it takes to drive 100 km. Lower is better. It is the standard in Europe, China and Australia.

What is 17 miles per gallon in liters per 100 km?

17 miles per gallon = 13.84 liters per 100 km. Calculated with the formula above.

What is 7.2 liters per 100 km in miles per gallon?

7.2 liters per 100 km = 32.67 miles per gallon.

How do I convert miles per gallon to liters per 100 km in my head?

Use 235 ÷ mpg. For 17 mpg that gives about 13.82 L/100 km instead of 13.84 L/100 km (0.091% too low).

Why is higher mpg better but higher L/100 km worse?

mpg is distance per fuel and L/100 km is fuel per distance, so they are reciprocals. Going from 20 to 30 mpg saves 3.92 L/100 km; from 40 to 50 mpg saves only 1.18.

About these units

kilometer per liter (km/L)

Kilometers per liter (km/L) is the distance driven on one liter of fuel, the usual fuel economy figure in Korea, Japan and India.

liter per 100 km (L/100 km)

Liters per 100 km measures how much fuel it takes to drive 100 km. Lower is better. It is the standard in Europe, China and Australia.

What is 15 kilometers per liter in liters per 100 km?

15 kilometers per liter = 6.667 liters per 100 km. Calculated with the formula above.

What is 1 liter per 100 km in kilometers per liter?

1 liter per 100 km = 100 kilometers per liter.

How do I convert kilometers per liter to liters per 100 km in my head?

100 ÷ km/L is exact, not an estimate. Example: 15 km/L = 6.667 L/100 km.

How do I compare a car rated in km/L with one rated in mpg?

Convert both to L/100 km: 15 km/L = 6.67 L/100 km and 35 mpg (US) = 6.72 L/100 km, so they are almost the same.

About these units

degree (°)

A degree (°) is 1/360 of a full turn.

radian (rad)

A radian is the angle made by an arc as long as the radius, about 57.2958°. Trig functions in maths and programming use radians.

Reverse conversion: Radians to Degrees

90 ° = 1.570796327 rad

Formula: rad = ° × 0.01745329252

Height (feet + inches ↔ cm)

How to convert degrees to radians

Start from the exact relation: 1 ° = 0.01745329252 rad

Put your value into the formula: rad = ° × 0.01745329

Round to the precision you need. The tables on this page show 2 to 3 decimals.

90 × 0.01745329 = 1.571 rad

0 × 0.01745329 = 0 rad

Mental-math shortcut

Use ° ÷ 57.3. For 90 ° that gives about 1.571 rad instead of 1.571 rad (0.0074% too low).

Definition and source: A full turn is 360° = 2π rad, so 1 rad = 180/π ° ≈ 57.29578° and 1° = π/180 rad ≈ 0.0174533 rad. The radian is the SI unit of plane angle. Source: BIPM, The International System of Units (SI Brochure, 9th ed., 2019) (checked 2026-10-12).

Radians to Degrees →

More angle conversions

What is 90 degrees in radians?

90 degrees = 1.571 radians. Multiply the value in ° by 0.01745329.

What is 0.5 radians in degrees?

0.5 radians = 28.65 degrees.

How do I convert degrees to radians in my head?

Why doesn’t my calculator give 1 for sin(90)?

It may be in radian mode: sin(90 rad) = 0.894, while sin(90°) = 1. Programming languages such as JavaScript and Python also expect radians.

About these units

radian (rad)

A radian is the angle made by an arc as long as the radius, about 57.2958°. Trig functions in maths and programming use radians.

degree (°)

A degree (°) is 1/360 of a full turn.

Reverse conversion: Degrees to Radians

1 rad = 57.29577951 °

Formula: ° = rad × 57.29577951

Height (feet + inches ↔ cm)

1 rad in other units

How to convert radians to degrees

Start from the exact relation: 1 rad = 57.29577951 °

Put your value into the formula: ° = rad × 57.29578

Round to the precision you need. The tables on this page show 2 to 3 decimals.

0.5 × 57.29578 = 28.65 °

0.1 × 57.29578 = 5.73 °

Mental-math shortcut

Use rad × 57.3. For 0.5 rad that gives about 28.65 ° instead of 28.65 ° (0.0074% too high).

Definition and source: A full turn is 360° = 2π rad, so 1 rad = 180/π ° ≈ 57.29578° and 1° = π/180 rad ≈ 0.0174533 rad. The radian is the SI unit of plane angle. Source: BIPM, The International System of Units (SI Brochure, 9th ed., 2019) (checked 2026-10-12).

Degrees to Radians →

More angle conversions

What is 0.5 radians in degrees?

0.5 radians = 28.65 degrees. Multiply the value in rad by 57.29578.

What is 90 degrees in radians?

90 degrees = 1.571 radians.

How do I convert radians to degrees in my head?

What are common radian values in degrees?

π/6 = 30°, π/4 = 45°, π/3 = 60°, π/2 = 90°, π = 180° and 2π = 360°.

Screen sizes are diagonals

A 65-inch TV has a 65-inch (about 165 cm) diagonal, and the aspect ratio sets the width and height. On a 16:9 screen, width ≈ diagonal × 0.8716 and height ≈ diagonal × 0.4903, so a 65-inch picture is about 143.9 × 80.9 cm (56.7 × 31.9 in). Bezels and stands are not included, so check the product's outer dimensions when measuring your space.

Viewing distance and pixel density

The suggested viewing distance is where the screen fills 30° to 40° of your view, the range recommended by the film industry. "Pixels blend in from" is the distance at which one pixel spans one arcminute, the detail limit of 20/20 vision. Sitting closer than that is where higher resolutions make a visible difference.

Aspect ratios

16:9: TVs and most monitors and laptops

21:9 (really 64:27): ultrawide monitors

16:10 and 3:2: some laptops and tablets

19.5:9 and 20:9: recent smartphones

How big is a 65-inch TV?

The 16:9 picture is about 56.7 × 31.9 in (143.9 × 80.9 cm). The full set with bezels is slightly larger and varies by model.

How many cm is a 27-inch monitor?

The diagonal is about 68.6 cm. A 16:9 panel is about 59.8 cm wide and 33.6 cm tall.

How base conversion works

To convert a decimal number to another base, keep dividing by the base and read the remainders backwards. For 13 in binary: 13 ÷ 2 = 6 remainder 1, 6 ÷ 2 = 3 remainder 0, 3 ÷ 2 = 1 remainder 1, 1 ÷ 2 = 0 remainder 1, giving 1101. Going back, 1101 is 1×8 + 1×4 + 0×2 + 1×1 = 13.

Hexadecimal uses 0 to 9 and A to F (10 to 15). Four binary digits map to one hex digit, which is why hex is used for colour codes (#FF8800) and memory addresses.

Octal groups binary digits in threes and shows up in Linux file permissions (755).

Numbers starting with 0x, 0b or 0o can be pasted as they are.

The tool works with whole numbers of any length and stays exact for very large values.

What is 255 in binary?

11111111. In hex it is FF and in octal 377.

How are negative numbers shown?

With a minus sign, like -1010, together with the 8, 16, 32 or 64-bit two's complement value.

How to read Roman numerals

Seven letters are used: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500 and M = 1,000. Write the largest values first and add them up. A smaller value in front of a larger one is subtracted, and only six such pairs exist: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).

2026 = MM + XX + VI = MMXXVI

1994 = M + CM + XC + IV = MCMXCIV

A letter repeats at most three times, so 4 is IV rather than IIII, although clock faces often show IIII.

There is no symbol for zero, and standard notation stops at 3,999 (MMMCMXCIX). Larger numbers put a bar over letters (the vinculum) to multiply them by 1,000.

What is 2026 in Roman numerals?

MMXXVI.

Is there a Roman numeral for zero?

No. Some medieval writers used N, from the Latin nulla (nothing), but it is not part of the standard system.

Writing amounts on checks

On a US check, write the dollars in words and the cents as a fraction of 100: "One thousand two hundred thirty-four and 50/100 dollars". Draw a line through the empty space after it so nothing can be added. Numbers from twenty-one to ninety-nine take a hyphen.

Other languages

Spanish: "mil doscientos treinta y cuatro". Mexican checks read "MIL DOSCIENTOS TREINTA Y CUATRO PESOS 50/100 M.N."

Chinese uppercase RMB, used on invoices and checks: 壹仟贰佰叁拾肆元伍角整

Japanese formal numerals (daiji) on receipts: 金壱千弐百参拾四円也

Korean contracts: 일금 일천이백삼십사원정

English uses the short scale, so a billion is 1,000,000,000. Spanish uses the long scale: "mil millones" is 1,000,000,000 and "un billón" is 1,000,000,000,000.

How do I write cents on a check?

Write the dollars in words and the cents as a fraction, like "and 50/100". With no cents, write "and 00/100".

Do I need "and" in English numbers?

American usage leaves it out ("one hundred five"), while British usage adds it ("one hundred and five"). Tick the British option to include it.

What is BMI?

Body mass index (BMI) is your weight divided by the square of your height. It shows how heavy you are for your height. Because it is simple and correlates well with body fat, it is the most widely used screen for underweight, overweight and obesity in adults.

BMI = weight (kg) ÷ height (m)²

For example, 65 kg at 170 cm gives 65 ÷ (1.7 × 1.7) ≈ 22.5. With pounds and inches, use 703 × weight (lb) ÷ height (in)²: 5 ft 9 in (69 in) and 160 lb give 703 × 160 ÷ 69² ≈ 23.6. This calculator rounds BMI to one decimal place and then compares it with the chosen table.

Why the cut-offs differ by country

The World Health Organization (WHO) classes a BMI under 18.5 as underweight, 18.5 to 24.9 as normal, 25 or more as overweight and 30 or more as obese, with obesity split into three classes at 30, 35 and 40. Evidence has built up, however, that Asian populations show a different link between BMI, body fat and health risk than European populations, and that many Asian people already have a high risk of type 2 diabetes and heart disease below a BMI of 25. In 2004 a WHO expert consultation kept the international cut-offs but listed extra public health action points at BMI 23, 27.5, 32.5 and 37.5 for countries to consider.

Korea: the Korean Society for the Study of Obesity (KSSO) 2022 guideline calls 23 to 24.9 pre-obese (overweight or at-risk weight) and 25 or more obese, with classes I to III starting at 25, 30 and 35. Class III is also called severe obesity.

Japan: the Japan Society for the Study of Obesity (JASSO) calls 25 or more obese, in grades 1 to 4. Being obese does not by itself mean "obesity disease" that needs weight loss, and a BMI of 22, where illness is least common, is used for standard body weight.

China: health standard WS/T 428-2013 (weight criteria for adults) classes 18.5 to 23.9 as normal, 24 to 27.9 as overweight and 28 or more as obese.

So the same BMI of 24 is normal under WHO and Japanese cut-offs, pre-obese in Korea and overweight in China. Switch the standard in the calculator above to compare.

Limits of BMI

It cannot tell muscle from fat. Very muscular people can have a high BMI without much body fat.

It does not show where fat sits. Fat around the waist is more closely tied to health risk, so waist circumference is checked too. KSSO, for example, defines abdominal obesity in Korean adults as a waist of 90 cm or more in men and 85 cm or more in women.

Older adults and people who are pregnant or breastfeeding: the link between BMI and body fat is weaker.

Children and teens are still growing, so adult cut-offs do not apply. They are assessed with age- and sex-specific growth references; WHO uses BMI-for-age for ages 5 to 19.

BMI is a starting point, not a diagnosis. Blood pressure, blood sugar, cholesterol and habits matter too, so discuss your results with a health professional.

How to measure accurately

Body weight changes during the day, so weigh yourself at the same time and under the same conditions each time, for example in the morning before eating, after using the toilet and in light clothing. Measure height without shoes, with heels, buttocks and shoulders against a wall. Your last values, units and standard are saved only in this browser, so they are still there next time.

What is the BMI for 170 cm and 65 kg?

65 ÷ 1.7² ≈ 22.5. That is in the normal range under the WHO, Korean, Japanese and Chinese cut-offs.

Is a BMI of 23 obese?

No. Under the Korean (KSSO) cut-offs, 23 to 24.9 is pre-obese (overweight or at-risk weight) and obesity starts at 25. It is normal under the WHO and Japanese cut-offs, and also normal in China (18.5 to 23.9).

Are BMI cut-offs different for women and men?

No, adult cut-offs are the same for both sexes. WHO states that its adult BMI ranges do not depend on age or sex, and the Japanese standard weight (BMI 22) is also the same for women and men. Body fat at a given BMI can still differ from person to person.

Can children and teens use this calculator?

It will compute the number, but the categories are for adults. Children and teens are assessed against age- and sex-specific growth references (BMI-for-age percentiles), so ask a paediatrician or use your country's child growth charts.