Converters
Convert units of length, weight, area, temperature, volume, speed, data, energy, pressure and more, all with exact factors.
Unit conversions with the exact factors, including the ones where the two systems disagree about what a gallon or a ton is, and the pairs that are nearly but not quite the same unit.
Convert between degrees, radians, gradians, turns, arcminutes and arcseconds.
Area ConverterConvert between square metres, square feet, hectares, acres and the rest.
Data Storage ConverterConvert between bytes, kilobytes, gigabytes and their binary counterparts, which are not the same thing.
Data Transfer Rate ConverterConvert between megabits per second, megabytes per second and every other bit and byte rate.
Energy ConverterConvert between joules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, foot-pounds and electronvolts.
Frequency ConverterConvert between hertz, kilohertz, megahertz, gigahertz and revolutions per minute.
Length ConverterConvert between metres, kilometres, miles, feet, inches and the rest, with exact factors.
Power ConverterConvert between watts, kilowatts, megawatts, both kinds of horsepower and BTU per hour.
Pressure ConverterConvert between pascals, hectopascals, bars, millibars, psi, atmospheres, torr and millimetres of mercury.
Roman Numeral ConverterConvert Roman numerals to numbers and back, with malformed numerals refused rather than guessed at.
Speed ConverterConvert between kilometres per hour, miles per hour, knots and metres per second.
Temperature ConverterConvert between Celsius, Fahrenheit, Kelvin and Rankine: each scale starts somewhere else, so the zero is shifted before scaling.
Time Unit ConverterConvert a duration between nanoseconds, milliseconds, seconds, minutes, hours, days and weeks.
Volume ConverterConvert between litres, gallons, pints and cups, keeping US and imperial measures apart.
Weight ConverterConvert between kilograms, grams, pounds, ounces, stones, tonnes, and the US short ton and UK long ton.