Unit Converter
Convert length, weight, temperature, volume, speed and area.
Result
1 mi = 1.609344 km
How to use the Unit Converter
- Choose what you want to convert, such as length or temperature.
- Pick the units in the 'From' and 'To' menus.
- Type a value in either box. The other box shows the converted amount.
- Use the swap button to reverse the units, and copy the result if needed.
About the Unit Converter
Convert between everyday units in seconds. This unit converter covers length, weight, temperature, volume, speed and area, with both metric and imperial units. It works in both directions: type in either box and the other updates immediately, so you can check a recipe, a road sign, a floor plan or a shipping weight without a separate lookup.
For length, weight, volume, speed and area, every unit is defined by how many base units it contains: the metre, kilogram, litre, metre per second and square metre. A conversion multiplies your value by the size of the starting unit and divides by the size of the target unit. For example, one mile is 1,609.344 metres and one kilometre is 1,000 metres, so one mile is 1.609344 kilometres.
Temperature scales do not share a zero point, so they use formulas instead: °F = °C × 9/5 + 32 and K = °C + 273.15. The tool converts through Celsius and refuses values below absolute zero. The definitions used are the international ones, and US and UK gallons are listed separately because they differ. Results show up to ten significant digits.
Frequently asked questions
Why are there US and UK gallons?
They are different sizes. A US gallon is 3.785 litres and a UK (imperial) gallon is 4.546 litres, so choose the one that matches where you are.
How do I convert Celsius to Fahrenheit?
Multiply by 9, divide by 5 and add 32. For example, 100°C × 9 ÷ 5 + 32 = 212°F. The tool does this for you.
Can I type in the second box?
Yes. Whichever box you type in is treated as the starting value and the other box is calculated.
How precise are the results?
Results are rounded to ten significant digits, which is far more precise than any everyday use needs.
Why can't I convert between different groups, such as metres and kilograms?
They measure different things. Choose a group first, then pick units from that group only.