Everyday math · Conversion

Unit converter

Convert length, weight, temperature, volume, area, and speed between metric and imperial units.

Convert

Converted value
—
—
Rate—

Rough sheet

step-by-step
BMI Calculator Currency Converter Percentage Calculator Scientific Calculator

Why temperature is different

Length, weight, volume, area, and speed conversions all work by multiplying your value by a fixed ratio between units — there's a single conversion factor between, say, miles and kilometers. Temperature is the exception: converting between Celsius, Fahrenheit, and Kelvin requires both multiplying and adding or subtracting an offset, because the three scales don't share a common zero point, which is why temperature can't use the same simple ratio approach as the other categories.

Frequently asked questions

Length, weight, volume, area, and speed all scale by simple multiplication, but Celsius, Fahrenheit, and Kelvin have different zero points, so converting between them needs an offset as well as a scale factor.

Yes, the conversion factors used are the standard defined equivalents (for example, exactly 2.54 centimeters to an inch), so results are precise to the decimal places shown.