ConverterUnit converter
Pick what you are converting, type the amount and choose the two units. The answer shows the sum and the definition behind it, and the same amount in every other unit of that kind.
- Length: mm, cm, m, km, inches, feet, yards, miles, nautical miles.
- Weight: mg, g, kg, tonnes, ounces, pounds, stone, US and UK tons.
- Volume, area and speed, from teaspoons to cubic feet and acres to knots.
- Free
- Works offline after your first visit
- Saves on this device
- No sign-up
- Updated
- Size 25 KB
Try an example
- cm to inches30 cm
- Inches to cmA 12 inch ruler
- Feet to meters6 feet
- kg to lbs70 kg
- lbs to kg150 lb
- Stone to kg11 stone
- Miles to km26.2 miles
- Liters to gallons (US)20 liters
- Liters to gallons (UK)20 liters
- Square feet to m²A 1,500 sq ft home
- Acres to hectares5 acres
- mph to km/h65 mph
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Questions
How many centimeters are in an inch?
Exactly 2.54. The inch has been defined as 2.54 cm since 1959, so 12 inches is 30.48 cm and 30 cm is about 11.811 inches.
How many pounds are in a kilogram?
About 2.20462. A pound is defined as exactly 0.45359237 kg, so to turn kilograms into pounds the converter divides by that number.
Which gallon does it use?
Both, labelled. A US gallon is 3.785411784 liters and a UK gallon is 4.54609 liters. US and UK pints, quarts and fluid ounces are separate units too.
Is a mile the US survey mile?
No. It is the international mile, 1,609.344 m exactly, which US law uses for everything since 2023. The old survey mile differs by about 3 mm.
Why do some answers have ≈?
The answer is exact when it ends within the digits shown, like 12 in = 30.48 cm. When it would run on, it is rounded to six figures and marked ≈.
A question we didn’t answer? Email support@handeware.com and a real person will reply.