Unit Converter
Length, weight, temperature and more.
Runs entirely in your browser. Nothing you enter or upload leaves your device.
What the unit converter does
This converter changes a measurement from one unit to another across ten categories: length, weight, temperature, volume, area, speed, time, data, pressure and energy. Metric units sit alongside imperial and US customary ones, so you can move between the systems used in recipes, travel, DIY, schoolwork and technical specifications.
Typical jobs include turning a recipe’s cups into millilitres, tyre pressure from PSI into bar, a speed limit in miles per hour into kilometres per hour, or a file size in gigabytes into gibibytes.
How to use the unit converter
- Pick a category. The page remembers it for next time.
- Enter a value and choose the units to convert from and to. Use the swap button to reverse them.
- The table below shows the value in every unit of the category at once.
Understanding the results
Under the main result, a line spells out the conversion and the rate for one unit, for example how many feet make one metre. Very large or very small results switch to scientific notation, such as 1.5e-7. You can type numbers that way too, and commas in large numbers are ignored.
Temperature works differently from the other categories, because the scales do not share a zero point. The tool converts through Celsius using the standard formulas, and warns you if a value falls below absolute zero (−273.15 °C).
Questions
How accurate are the conversions?
They use exact international definitions where they exist (for example 1 inch = 2.54 cm, 1 pound = 0.45359237 kg) and are shown to 10 significant digits.
Why are there two kinds of gigabyte?
GB uses powers of 1000 and is used by drive makers; GiB uses powers of 1024 and is what many operating systems show. That is why a 1 TB drive appears as about 931 GiB.
Are US and UK gallons the same?
No. A US gallon is 3.785 litres and a UK gallon is 4.546 litres. Both are listed. The teaspoon, tablespoon, fluid ounce, cup, pint and quart in the list are US measures.
Are food calories the same as calories here?
Food labels that say “calories” almost always mean kilocalories, so choose Kilocalorie for those figures. One kilocalorie is 4.184 kilojoules.
How long is a year in the time category?
365.25 days, the average length of a calendar year once leap years are included. Months are not listed because their length varies.
Is my input sent anywhere?
No. Every conversion is calculated in your browser as you type.