Temperature Converter

Convert between Celsius, Fahrenheit and Kelvin instantly.

Type in any one field — the other two update automatically.

What is the Temperature Converter?

This tool converts a temperature between the three scales in common use — Celsius (used by most of the world), Fahrenheit (used mainly in the United States), and Kelvin (used in science and engineering) — updating all three fields live as you type into any one of them.

The exact formulas used

Kelvin is an absolute scale — 0 K is absolute zero, the coldest temperature theoretically possible, which is why Kelvin is never expressed as a negative number and doesn't use a degree symbol. Fahrenheit and Celsius are both offset scales that can go negative. This distinction matters in scientific contexts (gas law calculations require Kelvin), while Celsius and Fahrenheit cover virtually all everyday use, from weather forecasts to oven temperatures to body temperature readings.

Want the "why" behind this tool? Read Why Fahrenheit Has Such Strange Round Numbers.