Celsius to Kelvin Converter
Convert Celsius to Kelvin instantly. K = °C + 273.15. Formula, table and why Kelvin has no negative numbers or degree sign.
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Quick answer
To convert Celsius to Kelvin, add 273.15: K = °C + 273.15. So 0°C (freezing point of water) is 273.15 K, and 25°C (a common "room temperature" reference) is 298.15 K.
C to K conversion table
| C | K |
|---|---|
| 1 C | 274.15 K |
| 2 C | 275.15 K |
| 3 C | 276.15 K |
| 4 C | 277.15 K |
| 5 C | 278.15 K |
| 6 C | 279.15 K |
| 7 C | 280.15 K |
| 8 C | 281.15 K |
| 9 C | 282.15 K |
| 10 C | 283.15 K |
| 20 C | 293.15 K |
| 30 C | 303.15 K |
| 40 C | 313.15 K |
| 50 C | 323.15 K |
| 60 C | 333.15 K |
| 70 C | 343.15 K |
| 80 C | 353.15 K |
| 90 C | 363.15 K |
| 100 C | 373.15 K |
| 250 C | 523.15 K |
| 500 C | 773.15 K |
| 1000 C | 1273.15 K |
How to convert C to K
This is the simplest conversion on the whole site (a plain addition, no multiplication at all), because Kelvin and Celsius use exactly the same size of degree; they only disagree about where zero sits. Celsius puts zero at water's freezing point; Kelvin puts zero at absolute zero, the coldest temperature theoretically possible, which is −273.15°C.
Kelvin values are never written with a degree symbol (it is "300 K," not "300°K") and are never negative, because the scale is defined so that 0 K is the absolute physical floor: there is nothing colder to convert to. This is also why scientific formulas involving temperature (gas laws, radiation, thermodynamics generally) almost always use Kelvin: a negative or zero-crossing temperature would break equations that involve dividing by temperature.