Unit converter

Convert units of 17 kinds.

From

To

1 m = 3.28084 ftfeet = meters × 3.280839895

1 m in every unit

How to convert units

Pick the kind of measurement: length, weight, temperature and so on.
Type a value in either box and choose the units on each side. The other side updates as you type.
Read the same value in every unit in the table below, and click a row to convert to that unit.

About these converters

Pick the kind of measurement first, such as length, weight or temperature, then the two units. There are 17 kinds, from everyday ones like cups and miles to engineering units for torque, force and pressure, and the table shows your value in every unit of that kind at once.

Length and weight conversions between metric and US or imperial units rest on two exact definitions agreed in 1959: the inch is exactly 2.54 cm and the pound is exactly 0.45359237 kg. Feet, yards, miles, ounces and stone all follow from those, so the answers are exact rather than approximate.

The usual traps are units that share a name. A US gallon is 3.785 liters and a UK gallon is 4.546 liters, a gigabyte can mean 1,000,000,000 bytes or 1,073,741,824, and a ton can be 907 kg, 1,000 kg or 1,016 kg. The unit names here say which one they mean.

Every converter

Length converter

Centimeters to inches, Inches to centimeters, Meters to feet, Feet to meters, Kilometers to miles, Miles to kilometers, Inches to feet, Feet to inches, Millimeters to inches, Inches to millimeters, Feet to centimeters, Centimeters to feet, Yards to meters, Meters to yards, Miles to feet, Inches to meters, Meters to inches, Feet to miles, Yards to feet, Feet to yards, Miles to meters, Meters to miles, Nautical miles to kilometers, Kilometers to nautical miles, Centimeters to meters, Meters to centimeters, Millimeters to centimeters, Centimeters to millimeters, Kilometers to meters, Meters to kilometers, Millimeters to feet, Micrometers (microns) to millimeters, Nanometers to meters, Light-years to kilometers

Weight converter

Kilograms to pounds, Pounds to kilograms, Grams to ounces, Ounces to grams, Stone to kilograms, Kilograms to stone, Ounces to pounds, Pounds to ounces, US tons to kilograms, Grams to pounds, Pounds to grams, Kilograms to ounces, Stone to pounds, Pounds to stone, Grams to kilograms, Kilograms to grams, Milligrams to grams, Grams to milligrams, Micrograms to milligrams, Milligrams to micrograms, US tons to pounds, Pounds to US tons, Carats to grams, Grams to carats, Troy ounces to grams, Grams to troy ounces

Temperature converter

Celsius to Fahrenheit, Fahrenheit to Celsius, Celsius to Kelvin, Kelvin to Celsius, Fahrenheit to Kelvin, Kelvin to Fahrenheit

Volume converter

Milliliters to fluid ounces, Fluid ounces to milliliters, Cups to milliliters, Milliliters to cups, Liters to gallons, Gallons to liters, Teaspoons to milliliters, Tablespoons to milliliters, Cups to fluid ounces, Fluid ounces to cups, Quarts to liters, Liters to quarts, Pints to liters, Cubic feet to gallons, Milliliters to teaspoons, Milliliters to tablespoons, Tablespoons to teaspoons, Cups to tablespoons, Liters to cups, UK gallons to liters, Fluid ounces to liters, Liters to fluid ounces, Cubic meters to cubic feet, Cubic feet to cubic meters, Milliliters to liters, Liters to milliliters, Cubic centimeters (cc) to milliliters, Milliliters to centiliters, Centiliters to milliliters, Gallons to cups, Cups to gallons, Quarts to cups, Pints to cups, Cups to pints

Area converter

Square feet to square meters, Square meters to square feet, Acres to hectares, Hectares to acres, Square feet to acres, Acres to square feet, Square miles to square kilometers, Square kilometers to square miles, Square meters to acres, Square yards to square meters, Square inches to square centimeters, Square feet to square yards

Speed converter

Miles per hour to km/h, Kilometers per hour to mph, Knots to miles per hour, Knots to kilometers per hour, Meters per second to kilometers per hour, Kilometers per hour to meters per second, Meters per second to miles per hour, Miles per hour to meters per second, Miles per hour to knots, Kilometers per hour to knots, Feet per second to miles per hour, Miles per hour to feet per second

Data storage converter

Megabytes to gigabytes, Gigabytes to megabytes, Kilobytes to megabytes, Megabytes to kilobytes, Gigabytes to terabytes, Terabytes to gigabytes, Gigabytes to gibibytes, Gibibytes to gigabytes, Kilobytes to bytes, Terabytes to tebibytes, Bits to bytes, Bytes to bits, Megabytes to terabytes

Time unit converter

Minutes to hours, Hours to minutes, Seconds to minutes, Hours to days, Seconds to hours, Days to weeks, Weeks to days, Weeks to months, Months to weeks, Years to days, Decades to years

Pressure converter

PSI to bar, Bar to PSI, PSI to kilopascals, Kilopascals to PSI, Atmospheres to PSI, Millimeters of mercury to kilopascals, Bar to kilopascals, Kilopascals to bar, Millibars to inches of mercury, Inches of mercury to millibars, Bar to atmospheres, Atmospheres to bar, Pascals to psi, Torr to pascals, Millimeters of mercury (mmHg) to psi, Hectopascals (hPa) to inches of mercury (inHg)

Energy converter

Joules to calories, Calories to joules, Kilocalories to kilojoules, Kilojoules to kilocalories, Kilowatt-hours to BTU, BTU to kilowatt-hours, Joules to kilowatt-hours, Electronvolts to joules, BTU to joules, Megawatt-hours to kilowatt-hours

Power converter

Horsepower to kilowatts, Kilowatts to horsepower, Watts to horsepower, BTU per hour to watts, Watts to BTU per hour, Kilowatts to BTU per hour, Horsepower to watts, Metric horsepower (PS) to horsepower, Kilowatts to metric horsepower (PS), Kilowatts to watts, Watts to kilowatts

Angle converter

Degrees to radians, Radians to degrees, Gradians to degrees, Arcminutes to degrees, Turns to degrees

Frequency converter

Hertz to RPM, RPM to hertz

Force converter

Newtons to pounds-force, Kilogram-force to newtons, Newtons to kilogram-force, Pounds-force to newtons

Torque converter

Newton meters to foot-pounds, Foot-pounds to newton meters, Inch-pounds to foot-pounds, Newton meters to inch-pounds, Kilogram-force meters to newton meters, Newton meters to kilogram-force meters

Data transfer rate converter

Megabits per second to megabytes per second

Fuel economy converter

MPG to liters per 100 km, Liters per 100 km to MPG, UK MPG to liters per 100 km, UK mpg to US mpg, Kilometers per liter to miles per gallon, Miles per gallon to kilometers per liter, US mpg to UK mpg

Questions

What kinds of units can I convert?

Length, weight, temperature, volume, area, speed, data size, time, pressure, energy, power, angle, frequency, force, torque, data transfer rate and fuel economy. Each kind also has its own converter page.

How do I convert metric to imperial?

Choose the kind of unit, put the metric unit on one side and the imperial or US unit on the other. The key exact factors are 1 in = 2.54 cm, 1 ft = 0.3048 m, 1 mile = 1.609344 km, 1 lb = 0.45359237 kg and 1 US gallon = 3.785411784 L.

What is the difference between US and imperial units?

Length and weight are the same in both. Volume is not: a US gallon is 3.785411784 L and an imperial gallon is 4.54609 L, a US pint is 473.18 ml and a UK pint is 568.26 ml. Tons differ too: the US short ton is 2,000 lb and the UK long ton is 2,240 lb.

Why can temperature not be converted with a single factor?

Celsius and Fahrenheit have different zero points as well as different degree sizes, so you multiply and then add: °F = °C × 9/5 + 32. Only kelvin and Rankine start at absolute zero.

Are the conversions exact?

Where a unit has an exact definition (the inch, the pound, the gallons, the calorie, the bar and many more) that definition is used, so the only rounding is in how many digits are shown.