Celsius to Kelvin Converter
Convert between Celsius and Kelvin instantly — no signup, nothing sent to a server.
Edit either field — the other updates automatically. K = °C + 273.15.
Formula, conversion table & examples
Formula
K = °C + 273.15
°C = K − 273.15
Celsius to Kelvin conversion table
| Celsius (°C) | Kelvin (K) |
|---|---|
| -273.15 | 0 |
| 0 | 273.15 |
| 20 | 293.15 |
| 37 | 310.15 |
| 100 | 373.15 |
Worked examples
- -273.15 °C = -273.15 × 1 + 273.15 = 0 K
- 0 °C = 0 × 1 + 273.15 = 273.15 K
- 373.15 K back to Celsius: 373.15 − 273.15 ÷ 1 = 100 °C
How to convert Celsius to Kelvin
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1
Enter a value in either field
Type a temperature into the Celsius field, or the Kelvin field — either direction works.
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2
Read the converted value
The other field updates instantly as you type.
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3
Adjust as needed
Keep editing either field to try different temperatures.
Example use cases
Science & lab work
Convert experimental or ambient temperatures to the Kelvin scale used in physics and chemistry.
Astronomy
Convert stellar or planetary temperature readings between Celsius and Kelvin.
Engineering & materials
Convert process or material temperatures for specifications that use absolute temperature.
Education
Check homework or exam answers involving the Kelvin scale.
Frequently asked questions
How do I convert Celsius to Kelvin?
Add 273.15 to the Celsius value. For example, 20°C + 273.15 = 293.15 K.
How do I convert Kelvin to Celsius?
Subtract 273.15 from the Kelvin value. For example, 293.15 K − 273.15 = 20°C.
Why is 273.15 the offset?
Kelvin uses the same size degree as Celsius but starts at absolute zero, which is exactly 273.15°C below the Celsius zero point — so the two scales differ only by this fixed offset, never a multiplier.
Is anything I type sent to a server?
No. Every conversion runs entirely in your browser — nothing is transmitted or logged.