What is 1 °C in Kelvin?

1 °C = 274.15 K. In the other direction, 1 K = -272.15 °C.

What is the Celsius scale?

The Celsius scale places 0 at the freezing point of water and 100 at its boiling point at standard pressure. It is the civil temperature scale almost everywhere outside the United States.

What is the Kelvin scale?

The kelvin is the SI base unit of thermodynamic temperature, starting at absolute zero. It shares Celsius’ degree size, so a rise of 1 K is a rise of 1 °C. Values are written without a degree symbol.

Unit-To-Unit Temperature conversion

Celsius to Kelvin

1 °C = 274.15 K

Add 273.15 and drop the degree symbol. Because the degree size is identical, a temperature difference is the same number in both scales — a 5 °C rise is a 5 K rise.

Formula K = °C + 273.15

Celsius (°C) max 24 digits

Kelvin (K) max 24 digits

Type in either field — the other updates on every keystroke. Need other units? Open the full temperature converter.

Celsius to Kelvin — quick reference
Celsius	Kelvin
-40 °C	233.15 K
-20 °C	253.15 K
-10 °C	263.15 K
0 °C	273.15 K
10 °C	283.15 K
20 °C	293.15 K
25 °C	298.15 K
30 °C	303.15 K
37 °C	310.15 K
50 °C	323.15 K
75 °C	348.15 K
100 °C	373.15 K
200 °C	473.15 K

Kelvin to Celsius — reverse
Kelvin	Celsius
-40 K	-313.15 °C
-20 K	-293.15 °C
-10 K	-283.15 °C
0 K	-273.15 °C
10 K	-263.15 °C
20 K	-253.15 °C
25 K	-248.15 °C
30 K	-243.15 °C
37 K	-236.15 °C
50 K	-223.15 °C
75 K	-198.15 °C
100 K	-173.15 °C
200 K	-73.15 °C

Worked examples

Common values
Situation	From	To
Absolute zero	-273.15 °C	0 K
Liquid nitrogen boils	-195.8 °C	77.35 K
Water freezes	0 °C	273.15 K
Room temperature	20 °C	293.15 K
Body temperature	37 °C	310.15 K
Water boils	100 °C	373.15 K

Mental-math shortcut

Add 273. The exact figure is 273.15.

Where this conversion comes up

Gas-law and chemistry calculations need kelvin. Bulb colour temperature is also quoted in kelvin, for example 2700 K for a warm white bulb.

Common mistakes

Kelvin has no degree sign, so write 300 K, not 300°K. A change of 1°C is a change of 1 K.

Background

The kelvin is named after Lord Kelvin. Since 2019 it is defined by fixing the value of the Boltzmann constant.

Learn more

Frequently asked

What is 1 °C in Kelvin?: 1 °C = 274.15 K. In the other direction, 1 K = -272.15 °C.
What is the Celsius scale?: The Celsius scale places 0 at the freezing point of water and 100 at its boiling point at standard pressure. It is the civil temperature scale almost everywhere outside the United States.
What is the Kelvin scale?: The kelvin is the SI base unit of thermodynamic temperature, starting at absolute zero. It shares Celsius’ degree size, so a rise of 1 K is a rise of 1 °C. Values are written without a degree symbol.
What is 0°C in kelvin?: 0°C is 273.15 K.

Related temperature conversions

Celsius to Fahrenheit Fahrenheit to Celsius Kelvin to Celsius Fahrenheit to Kelvin Rankine to Celsius