The Kelvin to Celsius formula
To convert Kelvin to Celsius, subtract 273.15: °C = K − 273.15. For example, 300 K − 273.15 = 26.85 °C. A change of 1 K equals a change of 1 °C, so only the offset differs. To reverse it, use the Celsius to Kelvin calculator.
A second example: a domestic freezer at 255 K is 255 − 273.15 = −18.15 °C, and a hot oven at 473.15 K is exactly 200 °C. Because the step size is shared, you can also convert a range in one move — 273.15 K to 373.15 K is simply 0 °C to 100 °C, the full liquid range of water at sea level.
Worth having open at the same time: the fahrenheit to celsius calculator.
How to convert K to °C
Enter a temperature in Kelvin and the calculator subtracts 273.15 to give Celsius. Kelvin is common in science, while Celsius is used for everyday weather and cooking. Room temperature is roughly 293–298 K, or about 20–25 °C.
Values in kelvin are never written with a degree symbol, so 300 K is correct and 300 °K is not. Kelvin readings are also always positive, which makes a negative input a reliable sign that a value was entered on the wrong scale.
Some reference points to check your answers against: liquid nitrogen boils at 77 K (−196.15 °C), water freezes at 273.15 K, average human body temperature is about 310 K (36.85 °C), and the surface of the Sun sits near 5,778 K. Colour temperatures for lighting use the same unit — a warm 2,700 K bulb and a daylight 6,500 K bulb describe emitted colour, not how hot the lamp gets.
If the next number you need is a related one, the celsius to fahrenheit calculator covers it.
Kelvin to Celsius reference table
| Kelvin | Celsius |
|---|---|
| 0 K | −273.15 °C |
| 273.15 K | 0 °C |
| 300 K | 26.85 °C |
| 373.15 K | 100 °C |
A quick pass through the fahrenheit to kelvin calculator saves a step later on.
Frequently asked questions
- What is 300 Kelvin in Celsius?
- 300 K equals 26.85 °C (300 − 273.15).
- What is the Kelvin to Celsius formula?
- °C = K − 273.15.
- What is 0 Kelvin in Celsius?
- 0 K is absolute zero, which equals −273.15 °C.
- How do I convert Celsius back to Kelvin?
- Add 273.15, or use the Celsius to Kelvin calculator.
- Why do scientists use Kelvin instead of Celsius?
- Because Kelvin starts at absolute zero, so its values are true ratios. A gas at 600 K really does hold twice the thermal energy of one at 300 K, whereas 60 °C is nowhere near twice as hot as 30 °C — a comparison that only works on an absolute scale.