Celsius to Kelvin Converter
Convert °C to Kelvin instantly. Free online calculator—add 273.15. For science labs and absolute temperature.
How to Convert Celsius to Kelvin
To convert Celsius to Kelvin, add 273.15 to the Celsius value.
Conversion Formula:
value + 273.15Conversion Examples
Example: 0 °C to K
- 0 + 273.15 = 273.15 K
0°C = 273.15 K
Water freezing.
Example: 25 °C to K
- 25 + 273.15 = 298.15 K
25°C = 298.15 K
Room temperature.
Conversion Chart
| Celsius | Kelvin |
|---|---|
| -50 | 223.15 |
| -20 | 253.15 |
| 0 | 273.15 |
| 10 | 283.15 |
| 20 | 293.15 |
| 25 | 298.15 |
| 30 | 303.15 |
| 50 | 323.15 |
| 75 | 348.15 |
| 100 | 373.15 |
Conversion Formula
Celsius and Kelvin use the same step size. Kelvin starts at absolute zero, which is −273.15°C, so adding 273.15 shifts any Celsius reading onto the absolute scale.
Quick Conversion Tip
Just add 273.15. Differences are identical: a 15°C rise equals a 15 K rise.
Unit Definitions
Celsius (°C)
Metric temperature scale with 0° at water freezing and 100° at boiling under standard pressure.
Shares degree size with Kelvin. Add 273.15 to reach Kelvin and subtract 273.15 from Kelvin to return to Celsius.
Kelvin (K)
Absolute temperature scale used in science and engineering, starting at absolute zero.
Same increment as Celsius but shifted by +273.15. Kelvin to Celsius subtracts 273.15; Kelvin to Fahrenheit uses (K − 273.15) × 9/5 + 32.
Common Use Cases
- Chemistry and physics labs.
- Thermodynamics problems.
- SI unit homework.
- Comparing weather °C to scientific K.
Understanding the Conversion
Celsius to Kelvin: K = °C + 273.15. Same size degree; Kelvin scale starts at absolute zero.
0°C = 273.15 K; 100°C = 373.15 K.
Chemistry and physics labs. The table and FAQ on this page walk through the factor if you need it.
FAQs
How do I convert °C to Kelvin?
Add 273.15 to Celsius.
Is a 1°C change the same as 1 K?
Yes—same increment size.
What is absolute zero in Celsius?
About −273.15°C.