Convert Celsius to Kelvin

Convert Celsius to Kelvin by adding 273.15. Covers the absolute zero concept, scientific calculations, color temperature, and thermodynamic applications.

Temperature

Detailed Explanation

Celsius to Kelvin Conversion

The conversion is the simplest of all temperature scales:

K = °C + 273.15

There is no multiplication or division — just add 273.15.

Key Reference Points

°C K Significance
-273.15 0 Absolute zero
-196 77.15 Liquid nitrogen boiling point
-78.5 194.65 Dry ice sublimation
0 273.15 Water freezes
20 293.15 Room temperature
37 310.15 Human body temperature
100 373.15 Water boils
1000 1273.15 Lava temperature
5500 5773.15 Sun surface temperature

Why Kelvin Matters in Science

Kelvin is the SI base unit of temperature. Unlike Celsius and Fahrenheit, Kelvin has no negative values because 0 K is absolute zero — the theoretical lowest temperature where molecular motion ceases. This makes Kelvin essential for:

  • Gas laws (PV = nRT uses Kelvin)
  • Thermodynamic calculations
  • Radiation formulas (Stefan-Boltzmann law, Wien's law)
  • Color temperature in photography and display calibration

Color Temperature

In photography and display technology, light color is measured in Kelvin:

  • 2700 K = Warm white (incandescent bulb)
  • 4000 K = Neutral white
  • 5500 K = Daylight
  • 6500 K = Cool daylight (D65 standard white point for monitors)

Degree Symbol

Kelvin does not use the degree symbol (°). It is written as simply "K", not "°K". This convention was adopted in 1967 by the International System of Units.

Use Case

A physics student needs to convert laboratory temperature readings from Celsius to Kelvin for thermodynamic calculations involving the ideal gas law.

Try It — Unit Converter

Open full tool