Temperature converter
Celsius to Kelvin Converter
Convert °C to K or reverse with one click. Type a value below for an instant result.
Celsius °C
Kelvin K
°C → K · runs in your browser, no server
How to convert celsius to kelvin
Celsius (°C) and Kelvin (K) both measure temperature. Whether you are studying, traveling, cooking, or working on a project, converting between them should be fast and accurate.
Looking for the opposite direction? See our dedicated kelvin to celsius converter — same formula reversed, with content written for that direction.
The standard relationship used on this page means that 1 celsius equals 274.15 K. Enter any number in the calculator — use the swap button to reverse the direction without leaving the page.
Converting 20 °C gives 293.15 K. This is a practical reference when switching between celsius and kelvin for weather forecasts, cooking, science labs, and HVAC settings.
Need kelvin to celsius instead? Try our Kelvin to Celsius converter. kelvin → celsius
When you'll use this
- Converting a lab temperature reading for a physics or chemistry gas-law calculation that requires absolute temperature
- Completing a science homework problem that specifies Celsius input but requires Kelvin for the formula
- Understanding an astronomy article's Celsius-stated temperature (e.g., a planet's surface) in the Kelvin scale scientists actually use
- Calibrating lab equipment or a scientific sensor that outputs readings in Kelvin
- Converting a materials-science specification (melting point, boiling point) from Celsius to Kelvin for engineering work
Practical note
This conversion shows up constantly in science coursework because many formulas — the ideal gas law being the classic example — only work correctly with an absolute temperature scale. A room-temperature reading of 20°C converts to exactly 293.15 K, the figure that actually needs to go into a gas-law equation; using 20 directly instead of 293.15 is one of the most common mistakes students make on chemistry homework. Because the Celsius-to-Kelvin relationship is pure addition rather than a scaled formula, it is one of the simpler temperature conversions to do by hand, but the 273.15 offset is easy to forget under exam pressure.
Tips
- The conversion is simple addition: Kelvin = Celsius + 273.15, with no multiplication or scaling involved, unlike the Celsius-to-Fahrenheit formula.
- Kelvin has no negative numbers in normal physics contexts — 0 K (absolute zero) is -273.15°C, so any realistic Celsius temperature converts to a positive Kelvin value.
- Gas law calculations (like the ideal gas law, PV = nRT) require absolute temperature — plugging in Celsius directly instead of Kelvin is one of the most common student errors in introductory chemistry.
Read our full guide: Celsius vs Fahrenheit explained
°C to K conversion table
| °C | K |
|---|---|
| -5 | 268.15 |
| 0 | 273.15 |
| 10 | 283.15 |
| 15 | 288.15 |
| 20 | 293.15 |
| 25 | 298.15 |
| 30 | 303.15 |
K to °C conversion table
Or click the swap button in the converter to switch from K to °C.
| K | °C |
|---|---|
| 268 | -5.15 |
| 273 | -0.15 |
| 283 | 9.85 |
| 288 | 14.85 |
| 293 | 19.85 |
| 298 | 24.85 |
| 303 | 29.85 |
Frequently asked questions
How many kelvins are in 1 celsius? +
One celsius equals 274.15 K. Use the converter above for any value — results are calculated locally with full precision.
How do I convert °C to K? +
Use the formula: K = °C + 273.15. Enter your value in the calculator and the result appears instantly. Click the swap button to convert K back to °C.
How many celsiuss are in 1 kelvin? +
One kelvin equals -272.15 °C. Swap the converter direction to work backwards from K to °C.
What is 10 °C in K? +
10 °C is 283.15 K. See the conversion table on this page for more common values.
When would I convert celsius to kelvin? +
This conversion is useful for weather forecasts, cooking, science labs, and HVAC settings. ConvertHub runs entirely in your browser — no data is uploaded to any server.
Is celsius to kelvin the same as kelvin to celsius? +
They are inverse operations. This page focuses on °C → K with examples and tables for that direction. For K → °C, use our separate kelvin to celsius converter page.