K
What is a Kelvin?
Temperature Unit
Definition
Kelvin is the SI base unit of temperature. It starts at absolute zero (0 K = -273.15°C), the theoretical point where all molecular motion stops.
Popular Kelvin Conversions
Most common conversions from Kelvin
History
The Kelvin scale was named after Lord Kelvin (William Thomson), who proposed an absolute temperature scale in 1848. It was adopted as an SI base unit in 1954.
Common Uses
- Scientific research and physics
- Color temperature in photography and lighting
- Astronomy and astrophysics
- Engineering and thermodynamics
Fun Facts
Kelvin does not use the degree symbol (just 'K', not '°K')
The surface of the Sun is about 5,778 K
The cosmic microwave background is about 2.7 K