Celsius to Kelvin (°C to K)
Result
274.15 Kelvin
Formula
K = °C + 273.15
The kelvin is the SI base unit, defined through the Boltzmann constant. A Celsius temperature is the kelvin temperature minus 273.15, and a Fahrenheit degree is 5/9 of a Celsius degree with water freezing at 32 °F. Rankine uses Fahrenheit-sized degrees from absolute zero.
Worked examples
- -273.15 °C × 1 + 273.15 = 0 K
- 0 °C × 1 + 273.15 = 273.15 K
- 25 °C × 1 + 273.15 = 298.15 K
- 100 °C × 1 + 273.15 = 373.15 K
Things to know about °C to K
- A kelvin and a Celsius degree are the same size, so only the zero point moves.
- Absolute zero, 0 K, is −273.15 °C. Kelvin values are written without a degree sign.
Celsius to Kelvin table
| Celsius (°C) | Kelvin (K) |
|---|---|
| -273.15 | 0 |
| 0 | 273.15 |
| 1 | 274.15 |
| 2 | 275.15 |
| 5 | 278.15 |
| 10 | 283.15 |
| 20 | 293.15 |
| 25 | 298.15 |
| 50 | 323.15 |
| 100 | 373.15 |
| 1,000 | 1,273.15 |
The units
- Celsius (°C)
- Celsius: the kelvin temperature minus 273.15. Water freezes at about 0 °C and boils at about 100 °C at sea level.
- Kelvin (K)
- The kelvin, the SI base unit of temperature, measured from absolute zero. A kelvin is the same size as a Celsius degree.
Sources for these factors
- The International System of Units (SI Brochure), 9th edition — BIPM
- Guide for the Use of the International System of Units (SP 811), Appendix B: conversion factors — NIST
- Handbook 44 (2024), Appendix C: General Tables of Units of Measurement — NIST
Last reviewed against these sources. An automated check recomputes every factor from its definition on each build. How we check accuracy