Unit Converter
Convert length, weight, temperature, area, volume and speed between metric and imperial units.
About unit conversion
Each unit is defined by its ratio to a base unit (for example metres for length), so converting is a matter of scaling by those ratios. Temperature is handled separately because its scales have different zero points.
FAQ
How accurate is it?
It uses exact internationally-defined conversion factors, so results are accurate to the digits shown.
For general use.
Use the result with confidence
Choose the measurement category
Select length, weight, area, volume, temperature or speed before choosing units. Enter the numerical value only; the selectors provide the units. Swapping units reverses the conversion direction, so check both labels before copying the result.
Check familiar conversions
1 metre = 100 centimetres. 1 square metre is about 10.763910 square feet; area conversion squares the length factor. Temperature is different: °F = °C × 9/5 + 32, so 0°C = 32°F. Multiplying a temperature by a simple unit ratio would be wrong.
US volume units and display precision
The gallon, quart, pint, cup and fluid ounce here use US customary volume. One US gallon is 3.785411784 litres, not an imperial gallon. Kilograms cannot be converted to litres without a material’s density. Results are rounded for display; retain extra precision for engineering or dosing work.
The example changes this calculator’s fields. It does not save or replace a journal or backup.