UnitConCelsius to Kelvin Converter
Convert Celsius to Kelvin for thermodynamics, chemistry, astrophysics, and any scientific calculation that requires absolute temperature. Kelvin is the SI base unit of temperature and is required in gas law calculations.
Formula
Add 273.15 to the Celsius value to get Kelvin. To reverse, subtract 273.15 from Kelvin to get Celsius.
Quick reference
| Celsius (°C) | Kelvin (K) |
|---|---|
| -273.15 | 0 |
| -196 | 77.15 |
| -40 | 233.15 |
| 0 | 273.15 |
| 20 | 293.15 |
| 37 | 310.15 |
| 100 | 373.15 |
| 200 | 473.15 |
| 300 | 573.15 |
| 500 | 773.15 |
About these units
Celsius
The Celsius scale anchors 0° at water's freezing point and 100° at its boiling point (at 1 atm). Defined in the 18th century, it became the international scientific and everyday temperature standard in the metric system.
Kelvin
Lord Kelvin (William Thomson) proposed the absolute temperature scale in 1848, anchoring zero at the theoretical minimum energy state. The kelvin was formally defined as 1/273.16 of the triple point of water in 1954, and redefined via Boltzmann's constant in 2019.
Frequently asked questions
0 + 273.15 = 273.15 K, the freezing point of water.
Absolute zero (0 K) equals -273.15°C.
Kelvin starts at absolute zero, which means equations like the ideal gas law (PV = nRT) work correctly — negative temperatures would cause division errors or unphysical results in those formulas.