Celsius to Kelvin Calculator
Convert Celsius temperature to Kelvin for chemistry, physics, thermodynamics, gas-law calculations, and engineering formulas that require absolute temperature. The form has one input, Temperature in Celsius, with a minimum of −273.15°C. It returns the Kelvin result to two decimal places.
Conversion formula
K = °C + 273.15
Celsius and Kelvin use the same interval size, so a change of 1°C is the same size as a change of 1 K. Only the zero point changes. Absolute zero is −273.15°C, which equals 0 K.
For example, 25°C + 273.15 = 298.15 K. A freezing-water reference of 0°C becomes 273.15 K, and 100°C becomes 373.15 K.
Common examples
| Celsius | Kelvin |
|---|---|
| −273.15°C | 0 K |
| 0°C | 273.15 K |
| 20°C | 293.15 K |
| 25°C | 298.15 K |
| 100°C | 373.15 K |
Use Kelvin whenever a formula depends on absolute temperature rather than a convenient weather scale. If you need Fahrenheit instead, use the Celsius to Fahrenheit calculator. For broader comparisons, see the temperature converter and energy converter.