Authoritative definitions of the International System of Units and SI prefixes.
Unit conversion
Celsius to Kelvin Converter
1 °C = 274.15 K. Enter a value to convert °C to K, then use the formula and table below. Displayed digits may be rounded.
TemperatureInstant result
Decimals
Formula result = input + 273.15. 1 °C = 274.15 K
Nonzero results too small for the selected decimal places use scientific notation.
Nonzero results too small for the selected decimal places use scientific notation.
Common examples
One value, several units
Fahrenheit33.8 °F
Kelvin274.15 K
Rankine493.47 °R
Conversion table
| °C | K |
|---|---|
| 1 °C | 274.15 K |
| 2 °C | 275.15 K |
| 5 °C | 278.15 K |
| 10 °C | 283.15 K |
| 25 °C | 298.15 K |
| 50 °C | 323.15 K |
| 100 °C | 373.15 K |
Conversion chart
1 °C274.15 K
5 °C278.15 K
10 °C283.15 K
25 °C298.15 K
50 °C323.15 K
Worked example
1 °C = 274.15 K. Apply the selected conversion formula to other input values.
Unit definition
Celsius (°C) Water freezes at 0 °C at standard pressure.
Unit history
The scale is named for Anders Celsius; its modern definition is tied to the kelvin with an exact offset of 273.15.
Step by step
1. Parse the value, including fractions.
2. Convert °C to kelvin.
3. Convert the base value to K and apply your display precision.
Understand the result before using it
Celsius to Kelvin converts a value measured in Celsius (°C) into the equivalent value in Kelvin (K). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = input + 273.15
Assumptions
- Celsius and Kelvin represent the same temperature quantity.
- The input is expressed in °C; the output is expressed in K.
- The unit definitions and conventional relationship shown on this page apply.
Worked example
1 °C = 274.15 K. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a °C measurement in a document that expects K.
- Compare a celsius value with a value reported in kelvin.
- Check the °C to K arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Temperature scales use offsets as well as scale factors, so a simple multiply-or-divide shortcut is not generally valid.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Celsius to Kelvin?
result = input + 273.15. Input is in °C; result is in K. 1 °C = 274.15 K. The displayed digits may be rounded.
What is 1 °C in K?
1 °C = 274.15 K. The displayed digits may be rounded. Use the full formula for other inputs; offset, reciprocal, and logarithmic scales cannot generally use this example as a multiplier.
Can I reverse the °C to K conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts K back to °C.
Is the Celsius to Kelvin result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.