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Celsius to Kelvin converter
Enter a number, fraction, power, π, or arithmetic expression.1 °C = 274.15 K K = °C + 273.15
Ready for local conversionCelsius to Kelvin formula
K = °C + 273.15
Add exactly 273.15; one Celsius degree interval equals one kelvin
Zero kelvin is absolute zero, corresponding to exactly −273.15 °C, while the size of each temperature interval is identical on both scales.
How to convert Degrees Celsius to Kelvin
Add exactly 273.15 to the Celsius value. Kelvin is written without a degree sign because it is an absolute thermodynamic unit.
Example calculation
A room temperature of 25 °C is exactly 298.15 K: 25 + 273.15 = 298.15.
25 °C = 298.15 K
When this conversion is useful
Use Celsius to kelvin for gas-law calculations, scientific reports, color temperature comparisons, laboratory work, and other absolute-temperature formulas.
Common Degrees Celsius to Kelvin conversions
| Degrees Celsius (°C) | Kelvin (K) |
|---|---|
| -273.15 | 0 |
| -40 | 233.15 |
| 0 | 273.15 |
| 20 | 293.15 |
| 100 | 373.15 |
| 1000 | 1273.15 |
Celsius to Kelvin FAQ
Add exactly 273.15 to the Celsius temperature.
It is exactly 273.15 K. Writing 273 K is a rounded approximation.
No. The unit is written as kelvin with the symbol K, not degrees Kelvin or °K.