Unit converter
Pick a category or search for a unit, type a value, and see it converted into every unit at once.
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Choose a result to convert from that unit.
Type a value to convert it.
In every unit
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How it works
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Choose what you’re measuring
Pick a category such as length or temperature, or type a unit name or symbol in the search box to jump straight to it.
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Type a value and pick the units
Enter the number with your usual decimal separator, choose the unit you have and the one you want. The swap button flips them.
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Read, check and copy
The result comes with the exact conversion factor, and the table below shows the same value in every other unit, each ready to copy.
Frequently asked questions
How many kilometers are in a mile?
One mile is exactly 1.609344 kilometers, because the international inch is defined as 2.54 cm. To go from kilometers to miles, divide by 1.609344.
How do I convert Celsius to Fahrenheit?
Multiply by 9/5, then add 32. For example, 20 °C × 9/5 + 32 = 68 °F. To go back, subtract 32 and multiply by 5/9. Kelvin is Celsius plus 273.15.
Is a gigabyte 1,000 or 1,024 megabytes?
In the standard (SI) sense, 1 GB is 1,000 MB, or 1,000,000,000 bytes. The binary unit, 1 GiB, is 1,024 MiB, or 1,073,741,824 bytes. Some operating systems label GiB values as “GB”, which is why a 500 GB drive can show about 465 “GB”.
Why are US and UK gallons different?
They come from different historical definitions. A US gallon is exactly 3.785411784 liters, and a UK (imperial) gallon is exactly 4.54609 liters, about 20 % larger. US and UK pints and fluid ounces differ too.
How precise are the conversions?
Each unit uses its exact legal definition (for example 1 lb = 0.45359237 kg, 1 atm = 101,325 Pa). Results show up to 10 significant digits, and very large or very small values switch to scientific notation.
Is anything I type sent to a server?
No. Every conversion is calculated in your browser. Only your last chosen category is remembered on this device, for your next visit.