About the Unit Converter
The Unit Converter changes a value between common units in three groups: length (metre, kilometre, centimetre, millimetre, mile, yard, foot, inch), weight (kilogram, gram, milligram, pound, ounce, stone) and temperature (Celsius, Fahrenheit, Kelvin).
Conversions use exact definitions, for example 1 inch = 25.4 mm and 1 pound = 0.45359237 kg. Temperature is converted with formulas rather than a multiplier, such as °F = °C × 9/5 + 32.
How to use it
- Choose a Category.
- Enter a Value and pick the From and To units.
- Use Swap units to reverse the direction.
Quick reference
1 mile ≈ 1.609 km. 1 kg ≈ 2.205 lb. 0 °C = 32 °F = 273.15 K.
Body temperature of 37 °C is 98.6 °F.
Results show up to eight decimal places, so round for everyday use.
Real-world examples
Cooking and DIY. 8 inches to centimetres is 20.32.
Travel. 26 miles is about 41.84 km; 75 °F is about 23.9 °C.
Fitness. 180 pounds is about 81.65 kg.
Common mistakes
Confusing weight and volume (a litre is not a kilogram for most things). Using the wrong temperature scale when reading recipes or weather. Rounding too early: keep extra digits and round only at the end.
How it works
Length and weight are converted by first changing the value into a base unit (metres or kilograms) and then into the target unit using exact factors. Temperature cannot use a single factor, so the tool converts through Celsius with formulas such as °C = (°F − 32) × 5/9 and K = °C + 273.15.
Frequently asked questions
Are results exact?
They use exact definitions, shown with limited decimals.
Can I convert volume?
Not yet.
Is anything stored?
No.