Celsius to Kelvin Converter
Convert Celsius to Kelvin and Kelvin to Celsius instantly. Free °C ↔ K calculator with formula and common temperatures table.Updated 2026-03-16
Formula: K = °C + 273.15 | °C = K − 273.15
Common Temperature Conversions
| Description | Celsius (°C) | Kelvin (K) |
|---|---|---|
| Absolute Zero | −273.15 °C | 0 K |
| Liquid Nitrogen | −196 °C | 77.15 K |
| Dry Ice | −78.5 °C | 194.65 K |
| Water Freezes | 0 °C | 273.15 K |
| Room Temperature | 20 °C | 293.15 K |
| Human Body | 37 °C | 310.15 K |
| Water Boils | 100 °C | 373.15 K |
| Oven (Hot) | 200 °C | 473.15 K |
| Iron Melts | 1538 °C | 1811.15 K |
| Sun Surface | 5500 °C | 5773.15 K |
How to Convert Celsius to Kelvin
To convert Celsius to Kelvin, simply add 273.15: K = °C + 273.15
For example, 25 °C = 25 + 273.15 = 298.15 K
To convert Kelvin to Celsius, subtract 273.15: °C = K − 273.15
💡 The Kelvin scale starts at absolute zero (0 K = −273.15 °C). A degree change in Celsius equals a degree change in Kelvin. All calculations happen locally in your browser.
Frequently Asked Questions
What is the formula for Celsius to Kelvin?
K = °C + 273.15. Simply add 273.15 to any Celsius temperature to get Kelvin.
What is 0 °C in Kelvin?
0 °C equals 273.15 K. This is the freezing point of water at standard atmospheric pressure.
What is absolute zero in Celsius?
Absolute zero is −273.15 °C (0 K). It is the lowest possible temperature where all molecular motion stops.
Why do scientists use Kelvin instead of Celsius?
Kelvin is the SI unit for temperature. It starts at absolute zero, making it ideal for scientific calculations involving gas laws, thermodynamics, and physics where negative temperatures would be problematic.
Is a degree in Celsius the same size as a Kelvin?
Yes! A change of 1 °C equals a change of 1 K. The scales are offset by 273.15 but have identical step sizes.