Convert between Celsius, Fahrenheit, and Kelvin temperature scales.
Celsius
Fahrenheit
Kelvin
Convert between Celsius, Fahrenheit, and Kelvin with one tool.
See results as you type without clicking any buttons.
Quick reference for important temperatures like boiling, freezing, and body temperature.
Properly handles below-zero temperatures across all scales.
Temperature conversion is frequently needed when reading international weather forecasts, following cooking recipes from other countries, or working in scientific contexts. Our converter handles all three major scales instantly.
Understanding temperature scales is important in science and engineering. Kelvin is used in physics and chemistry, Celsius in most of the world for weather and cooking, and Fahrenheit primarily in the United States.
For C to F, multiply first then add. For F to C, subtract first then multiply. Reversing the order gives wrong results.
A change of 10C equals a change of 18F, but 10C is not the same as 18F in absolute temperature.
Kelvin starts at absolute zero. Entering a negative Kelvin value is physically meaningless.
Rankine is the Fahrenheit-based absolute scale. Converting to Rankine requires different formulas than Kelvin.
Multiply by 9/5 and add 32. Formula: F = (C x 9/5) + 32. Example: 25C = (25 x 1.8) + 32 = 77F.
Subtract 32 and multiply by 5/9. Formula: C = (F - 32) x 5/9. Example: 72F = (72 - 32) x 5/9 = 22.2C.
Absolute zero is 0 Kelvin, -273.15C, or -459.67F. It is the theoretical lowest possible temperature where molecular motion stops.
Anders Celsius proposed his scale in 1742 (originally inverted). Daniel Fahrenheit developed his scale in 1724 using brine as 0F and body temperature as 96F.
The United States, Bahamas, Cayman Islands, Liberia, Palau, and some US territories use Fahrenheit. Almost all other countries use Celsius.