The most requested conversions
- Length: 1 inch = 2.54 cm; 1 foot = 30.48 cm; 1 yard = 0.9144 m; 1 mile = 1.609 km; 1 nautical mile = 1.852 km.
- Weight: 1 pound = 453.6 g; 1 ounce = 28.35 g; 1 stone = 6.35 kg; 1 kg = 2.205 pounds.
- Temperature: °F = °C × 9/5 + 32; °C = (°F − 32) × 5/9. 0 °C = 32 °F, 100 °C = 212 °F, 37 °C = 98.6 °F. Kelvin is °C + 273.15.
- Volume: 1 US gallon = 3.785 l; 1 fluid ounce = 29.57 ml; 1 US cup = 236.6 ml; 1 tablespoon = 14.8 ml; 1 teaspoon = 4.9 ml.
- Area: 1 acre = 4,047 m²; 1 hectare = 10,000 m²; 1 square foot = 0.0929 m².
- Speed: 1 mph = 1.609 km/h; 1 knot = 1.852 km/h; 1 m/s = 3.6 km/h.
- Data: 1 byte = 8 bits; 1 GB = 1,000 MB (decimal units, the ones used by manufacturers and providers); 100 Mbit/s = 12.5 MB/s.
Metric and imperial units
The metric system (metres, kilograms, litres) is used almost everywhere; imperial and US customary units (inches, pounds, gallons, Fahrenheit) remain common in the United States and partly in the UK. Mind the differences: the British gallon and pint are larger than the American ones (1 UK gallon = 4.546 l); this converter uses US measures, the most common online and in recipes.
Using the table
Below the result you get a table of values near the one you entered (for temperature, in steps of 5 and 10 degrees): handy for getting a feel without redoing the calculation, for example when reading a recipe or checking the weather forecast in another country.
Frequently asked questions
How many centimetres in an inch?
Exactly 2.54 cm. A 15.6-inch screen therefore measures about 39.6 cm diagonally.
How do I convert Fahrenheit to Celsius in my head?
Subtract 30 and halve it: 70 °F ≈ 20 °C (the exact value is 21.1 °C). For the reverse, double and add 30.
How much is a cup in millilitres?
A US cup is 236.6 ml, roughly 240 ml; a tablespoon is 14.8 ml and a teaspoon 4.9 ml.