Kelvin to Celsius
One K equals -272.15 °C. Type any number and the answer appears as you type — the maths happens in your browser.
The same value in every unit
| Unit | Value |
|---|
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Common values
| Kelvin | Celsius |
|---|---|
| -40 K | -313.15 °C |
| -20 K | -293.15 °C |
| -10 K | -283.15 °C |
| 0 K | -273.15 °C |
| 10 K | -263.15 °C |
| 20 K | -253.15 °C |
| 25 K | -248.15 °C |
| 30 K | -243.15 °C |
| 37 K | -236.15 °C |
| 50 K | -223.15 °C |
| 100 K | -173.15 °C |
| 200 K | -73.15 °C |
How to use
- Enter the number of Kelvin in the field.
- The result in Celsius updates on every keystroke.
- Use the table below for the values people look up most often.
Formula and reverse conversion
The formula
To convert by hand: °C = K − 273.15. Going back the other way, one °C is 274.15 K.
Why you cannot just multiply
Celsius, Fahrenheit and Kelvin start counting from different points, so a temperature is converted with a formula rather than a factor. That is why −40 is the same number in Celsius and Fahrenheit, and why a difference between two temperatures converts differently from a temperature itself.
°C = K − 273.15
Frequently asked questions
How many Celsius are in one Kelvin?
One K is -272.15 °C.
How do I convert Kelvin to Celsius?
Multiply by the factor: °C = K − 273.15.
Is the result exact?
The factors are the exact legal definitions, and up to ten significant digits are kept in the answer. Rounding happens only in the display.
How do I convert Celsius back to Kelvin?
One °C is 274.15 K — or open the reverse page linked below.