Celsius to Kelvin
K = °C + 273.15 — type a value and see the result instantly
1 °C = 274.15 K
⇄ Kelvin → CelsiusCelsius and Kelvin have the same step size, so converting is a simple shift: K = °C + 273.15. The reverse is °C = K − 273.15. For example, 25 °C = 298.15 K and 100 °C = 373.15 K.
Kelvin is the SI unit of thermodynamic temperature and starts at absolute zero (0 K = −273.15 °C), so it has no negative values and is written without a degree sign. Water freezes at 273.15 K and boils at 373.15 K; room temperature is about 293–295 K.
Kelvin is the SI base unit of temperature; one kelvin equals one degree Celsius in size. Lighting uses it for colour temperature: 2,700 K is warm white, 4,000 K neutral and 6,500 K daylight; the surface of the Sun is about 5,778 K.
Quick answers
Celsius to Kelvin conversion table
| Celsius (°C) | Kelvin (K) |
|---|---|
| −273.15 °C | 0 K |
| −200 °C | 73.15 K |
| −196 °C | 77.15 K |
| −100 °C | 173.15 K |
| −78.5 °C | 194.65 K |
| −50 °C | 223.15 K |
| −40 °C | 233.15 K |
| −20 °C | 253.15 K |
| −10 °C | 263.15 K |
| 0 °C | 273.15 K |
| 10 °C | 283.15 K |
| 20 °C | 293.15 K |
| 25 °C | 298.15 K |
| 30 °C | 303.15 K |
| 37 °C | 310.15 K |
| 40 °C | 313.15 K |
| 50 °C | 323.15 K |
| 60 °C | 333.15 K |
| 80 °C | 353.15 K |
| 100 °C | 373.15 K |
| 150 °C | 423.15 K |
| 200 °C | 473.15 K |
| 300 °C | 573.15 K |
| 500 °C | 773.15 K |
| 1,000 °C | 1,273.15 K |
Kelvin to Celsius quick table
| Kelvin (K) | Celsius (°C) |
|---|---|
| 0 K | −273.15 °C |
| 50 K | −223.15 °C |
| 100 K | −173.15 °C |
| 250 K | −23.15 °C |
| 280 K | 6.85 °C |
| 298.15 K | 25 °C |
| 310 K | 36.85 °C |
| 400 K | 126.85 °C |
| 1,000 K | 726.85 °C |
| 5,778 K | 5,504.85 °C |
Frequently Asked Questions
What is 100 °C in K?
100 °C = 373.15 K (K = °C + 273.15).
How do I convert Kelvin to Celsius?
°C = K − 273.15. For example, 298.15 K = 25 °C.
What is absolute zero?
Absolute zero is the lowest possible temperature: 0 K = −273.15 °C = −459.67 °F.
Why is there no degree sign with Kelvin?
Kelvin is an absolute SI unit, not a scale measured in degrees from a reference point, so it is written as 300 K, not 300 °K (the degree sign was dropped in 1967).