Unit converter
Convert length, weight, temperature, volume, area, speed, energy, power, pressure, fuel consumption and time between metric and imperial units.
How to use
Choose the type of measure, type the value and pick the unit you have and the unit you want. The result shows the conversion and, below it, the same value in every other unit of that type. Swap turns the conversion around, and the result updates as you type.
There are eleven types: length, weight and mass, temperature, volume and capacity (including US cups, spoons and pints, and imperial pints and gallons), area, speed, energy, power, pressure, fuel consumption and time. Results keep up to 10 significant digits, so exact conversions such as 1 inch = 2.54 cm show in full.
The factors are built from the exact definitions in the NIST guide to the SI and the UK Weights and Measures Act 1985: the inch is 2.54 cm, the yard 0.9144 m, the pound 0.45359237 kg, the US gallon 231 cubic inches and the imperial gallon 4.54609 litres. Temperature and fuel consumption are not simple multiples and are converted with their formulas.
Example
The example: 180 °C, a common oven temperature, is 356 °F and 453.15 K.
1 mile and 1 inch1.609344 km and 2.54 cm, both exact.180 °C in an oven recipe356 °F; 350 °F is about 176.7 °C.A car that uses 6.5 L/100 km36.19 miles per US gallon or 43.46 per imperial gallon.Tyres at 32 psi2.206 bar, or 220.6 kPa.
Frequently asked questions
Are US and UK gallons and pints the same?
No. The US gallon is 3.785 litres and the imperial gallon 4.546 litres, so a US pint is 473.18 mL and an imperial pint 568.26 mL. Fluid ounces differ the other way: 29.57 mL in the US and 28.41 mL in the UK.
What is the difference between hp and PS or CV?
Horsepower (hp) is 550 foot-pounds per second, about 745.7 W. The metric horsepower used in Europe and Latin America (PS, CV, ch, cv) is 735.5 W, so 100 PS is 98.63 hp.
Why does L/100 km go down when mpg goes up?
Because they measure opposite things: litres used per distance, or distance per gallon. One is 235.2 divided by the other for US gallons, so 6.5 L/100 km is 36.19 mpg (US) and 43.46 mpg with imperial gallons.
How many grams is a cup of flour?
It depends on the ingredient, because a cup measures volume. A US cup is 236.6 mL; the USDA food database gives 125 g for a cup of all-purpose flour and other ingredients weigh different amounts. This converter works with volumes and weights, not with ingredients.
Is a calorie on a food label the same as a calorie here?
The food Calorie is a kilocalorie (kcal), 4.184 kJ. A day’s 2,000 kcal is 8,368 kJ, or about 2.32 kWh.