Unit converters

Convert length, weight, temperature, speed and more. Free to use, no sign-up needed.

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15 tools

Length ConverterConvert between millimetres, metres, kilometres, inches, feet, yards and miles. Weight ConverterConvert between grams, kilograms, tonnes, ounces, pounds and stone. Area ConverterConvert between square metres, hectares, acres, square feet and square miles. Volume ConverterConvert between litres, millilitres, gallons, pints, cups and spoons. Speed ConverterConvert between metres per second, km/h, mph, knots and feet per second. Time ConverterConvert between milliseconds, seconds, minutes, hours, days, weeks and years. Data Storage ConverterConvert between bytes, kilobytes and megabytes, in both 1000 and 1024 forms. Pressure ConverterConvert between pascals, bar, PSI, atmospheres and millimetres of mercury. Energy ConverterConvert between joules, calories, kilocalories, watt hours and BTU. Power ConverterConvert between watts, kilowatts, megawatts and both kinds of horsepower. Angle ConverterConvert between degrees, radians, gradians, turns, arcminutes and arcseconds. Temperature ConverterConvert between Celsius, Fahrenheit, Kelvin and Rankine. Fuel Economy ConverterConvert between litres per 100 km, km per litre and miles per gallon. Number Base ConverterConvert numbers between binary, octal, decimal, hexadecimal and base 36. Roman Numeral ConverterTurn numbers into Roman numerals, or read Roman numerals back as numbers.

Good to know

How do I convert a value?

Choose the units to convert from and to, then enter the number without a unit or currency symbol.

Can I convert a whole column?

Yes. Paste one number per line. Each line uses the same pair of units.

Why are there several similar unit names?

Some units have different definitions, such as US and Imperial gallons or decimal and binary storage units. Choose the one used by your source. Any fixed month or year length is shown in the unit label.