Celsius to Kelvin Converter

Convert Celsius to kelvin instantly — the first step of every thermodynamics numerical.

Formula used

How to use this converter

  1. Type the temperature in the first box.
  2. Choose the starting scale and the target scale.
  3. The converted temperature shows right away.

The formula

Just add: K = °C + 273.15. Example: 25 °C + 273.15 = 298.15 K. It is the easiest temperature conversion there is.

Quick conversion table

CelsiusKelvinNote
−273.15 °C0 KAbsolute zero
0 °C273.15 KWater freezes
25 °C298.15 KRoom temperature
37 °C310.15 KBody temperature
100 °C373.15 KWater boils

Board exam essential

CBSE and state board physics papers love asking for temperatures in kelvin — gas law numericals in Class 11 basically require it. The common student mistake is adding 273 instead of 273.15; in board exams, the .15 can matter. This tool never forgets it.

Frequently asked questions

How do you convert celsius to kelvin?

Add 273.15: K = °C + 273.15.

What is 25°C in kelvin?

298.15 K.

Is it 273 or 273.15?

Exactly 273.15 — using 273 is an approximation teachers accept roughly, but 273.15 is correct.

What is −273.15°C in kelvin?

0 K — absolute zero.