Unit Converter

Kelvin to Celsius Converter

Convert Kelvin to Celsius instantly. 1 K = -272.15 °C. Free, accurate temperature conversion with formula and table.

Celsius

-272.15 °C

1 K = -272.15 °C

Kelvin to Celsius formula

°C = K − 273.15

Kelvin and Celsius are both absolute temperature scales commonly used in science. The Kelvin scale is the SI base unit, starting at absolute zero. Celsius is derived from Kelvin by subtracting 273.15, the reference point where water freezes at 0°C, which equals 273.15 K.

Kelvin to Celsius conversion table

Kelvin (K)Celsius (°C)
-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
40 K-233.15 °C
50 K-223.15 °C
100 K-173.15 °C

When you need to convert kelvin to celsius

  • Interpreting scientific research papers and thermodynamic data that use absolute temperature
  • Physics and chemistry experiments requiring precise temperature conversions
  • Understanding extreme temperatures in astrophysics and laboratory conditions
  • Converting equipment specifications and calibration data for industrial applications

Frequently asked questions

What is the formula for converting Kelvin to Celsius?

The formula is °C = K − 273.15. Simply subtract 273.15 from the Kelvin value to get Celsius. This works because Celsius is offset from Kelvin by exactly that amount.

Why is Kelvin used in science instead of Celsius?

Kelvin is the SI standard unit and starts at absolute zero, making it essential for thermodynamic calculations and gas laws. Celsius is more practical for everyday use, but scientific work requires Kelvin's absolute reference point.

Can Celsius temperatures be negative in Kelvin?

No. Kelvin cannot be negative because it starts at absolute zero. Negative Celsius values convert to positive Kelvin values below 273.15 K. For example, −40°C equals 233.15 K.

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FreeToolz Editorial Team · Last reviewed July 2026

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