Type conversions straight into the calculator
On the home page calculator you can type conversions in plain English: 5 ft 11 in to cm, 72 f to c, 2 cups in ml or 100 mph in km/h.
Handy conversions
| From | To | Multiply by |
|---|---|---|
| inches | centimeters | 2.54 (exact) |
| feet | meters | 0.3048 (exact) |
| miles | kilometers | 1.609344 (exact) |
| pounds | kilograms | 0.45359237 (exact) |
| ounces | grams | 28.3495 |
| US gallons | liters | 3.78541 |
| US cups | milliliters | 236.588 |
| acres | square feet | 43,560 |
| mph | km/h | 1.609344 |
Temperature
Temperature can't be converted by multiplying alone, because the scales start at different points:
°C = (°F − 32) × 5/9 °F = °C × 9/5 + 32 K = °C + 273.15
Water freezes at 32 °F (0 °C) and boils at 212 °F (100 °C) at sea level. −40 is the same in both.
Common mistakes
- Ounces vs fluid ounces. An ounce (oz) is weight; a fluid ounce (fl oz) is volume. They only match for water-like liquids: 8 fl oz of water weighs about 8.3 oz, but a cup (8 fl oz) of flour weighs only about 4.25 oz. Pick the right one in Weight or Volume.
- Temperature differences. A change of 10 °C is a change of 18 °F, not 50 °F. The +32 only applies to actual temperatures, not differences.
- US vs UK gallons and pints. A UK pint is 20 fl oz; a US pint is 16. Recipes from the UK need the imperial units.
- Square feet vs feet squared. A 10 ft square room is 100 sq ft, but "10 square feet" is a much smaller area (about 3.2 × 3.2 ft).
Notes
- "Ton" here means the US short ton (2,000 lb); "metric ton" is 1,000 kg.
- Gallons, quarts, pints, cups and fluid ounces are US measures. UK (imperial) gallons are about 20% bigger.
- KB, MB, GB use 1,000; KiB, MiB, GiB use 1,024, which is how some computers report file sizes.