Temperature Converter (Celsius, Fahrenheit, Kelvin)

Convert a temperature between Celsius, Fahrenheit, and Kelvin. Runs entirely in your browser.

How it works

Unlike length or weight, temperature scales don't share a zero point, so conversion needs an offset, not just a multiplication: Celsius and Kelvin share the same step size (1°C = 1K) but are shifted by 273.15; Fahrenheit both shifts and scales (1°C = 1.8°F of change). Kelvin is an absolute scale — 0 K is absolute zero, so negative Kelvin isn't physically meaningful.

Formulas: °F = °C × 9/5 + 32, K = °C + 273.15.

Common conversions

FromToResult
0 °C°F32 °F (freezing point of water)
100 °C°F212 °F (boiling point of water)
37 °C°F98.6 °F (average body temperature)
0 K°C-273.15 °C (absolute zero)

FAQ

What temperature is the same in Celsius and Fahrenheit?

-40° — it's the one point where both scales agree.

Why can't Kelvin be negative?

Kelvin measures temperature from absolute zero, the theoretical point where particles have minimum thermal motion — there's nothing colder, so nothing below 0 K.