Unit converter
Metric and imperial, for length, weight, temperature, volume, area, speed and data.
Recipes in cups, heights in feet, a hire car showing miles per hour, a hard drive quoted in gigabytes that your computer calls gibibytes: everyday conversions, each with its own small trap.
Pick a family, pick two units, and the answer updates as you type. Temperature gets proper formulas rather than a ratio, because Celsius, Fahrenheit and Kelvin don’t share a zero.
The data section keeps kilobytes (1,000 bytes) and kibibytes (1,024) apart, which is the reason a "500 GB" disk shows up as about 465 GB in your file manager.
How to use it
- Choose what you’re converting.
- Type the value.
- Pick the units on each side — swap them with one click.
Frequently asked questions
Why is my hard drive smaller than advertised?
Manufacturers count a gigabyte as 1,000,000,000 bytes; operating systems often show gibibytes (1,073,741,824). Same disk, different unit — convert between GB and GiB here to see it.
US or UK gallons?
Both are listed, because they differ by about 20%. US fluid ounces, cups, pints and gallons are the American measures; the UK gallon is separate.
How precise are the results?
Conversions use exact definitions (an inch is exactly 25.4 mm), and the display adapts its decimals to the size of the number.
Can I convert cooking measurements?
Volume conversions are here (teaspoons, tablespoons, cups, millilitres). Converting cups of flour to grams depends on the ingredient, so that needs a recipe-specific table.
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