🌡️ Kelvin to Celsius Converter
Instantly convert temperatures from Kelvin (K) to Celsius (°C). The Kelvin scale is the SI base unit for temperature, starting at absolute zero (0 K = −273.15 °C).
What Is the Kelvin Scale?
The Kelvin scale is the SI base unit for temperature, named after the British physicist Lord Kelvin (William Thomson) (1824–1907). It is an absolute thermodynamic temperature scale, meaning it starts at absolute zero, the point at which all molecular motion ceases.
Key characteristics of the Kelvin scale:
- Zero point: 0 K is absolute zero, equivalent to −273.15 °C.
- Degree size: A Kelvin is the same size as a degree Celsius — the scales use the same increment.
- Freezing point of water: 273.15 K (0 °C).
- Boiling point of water: 373.15 K (100 °C).
- No degree symbol: Temperatures in Kelvin are written as "K" (e.g., 300 K), not "°K".
The Kelvin scale is widely used in science, engineering, and thermodynamics because it allows for direct comparison of thermal energy and avoids negative values.
How to Convert Kelvin to Celsius
The formula to convert Kelvin to Celsius is:
°C = K − 273.15
Simply subtract 273.15 from any Kelvin temperature.
This formula works because the Celsius and Kelvin scales use the same degree size, but have different zero points. Celsius sets 0 °C at the freezing point of water, while Kelvin sets 0 K at absolute zero (−273.15 °C).
For example, to convert 373.15 K (the boiling point of water) to Celsius:
°C = 373.15 − 273.15
°C = 100.00 °C
Why Use This Converter?
- Instant results: Get accurate conversions in real-time.
- Step-by-step breakdown: See exactly how the conversion is calculated.
- Common reference table: Quickly check temperatures from 0 K to 1000 K.
- Free & private: No registration, no data storage — all calculations are done in your browser.
❓ Kelvin to Celsius FAQ
What is the formula to convert Kelvin to Celsius?
The formula is °C = K − 273.15. Simply subtract 273.15 from the Kelvin temperature.
What is the Kelvin scale used for?
The Kelvin scale is the SI base unit for temperature and is used in science, physics, chemistry, and engineering for thermodynamic calculations. It is the standard scale for measuring absolute temperature.
What is the difference between Kelvin and Celsius?
Both scales use the same degree size, but Celsius sets 0 °C at the freezing point of water, while Kelvin sets 0 K at absolute zero (−273.15 °C). The two scales differ only by a constant offset.
What is absolute zero in Celsius?
Absolute zero is −273.15 °C, which is equivalent to 0 K.
What is the freezing point of water in Kelvin?
Water freezes at 273.15 K (0 °C).
What is the boiling point of water in Kelvin?
Water boils at 373.15 K (100 °C).
Who invented the Kelvin scale?
The Kelvin scale was invented by Lord Kelvin (William Thomson) (1824–1907), a British physicist and engineer.
Why is there no degree symbol with Kelvin?
Kelvin is an absolute temperature scale, and the unit is simply called "Kelvin" (symbol: K), not "degrees Kelvin" (not °K). The degree symbol is not used with absolute temperature scales.
How accurate is this converter?
This converter provides highly accurate results using the standard conversion formula °C = K − 273.15. You can adjust the decimal precision to suit your needs.
Is this converter free?
Yes, this converter is completely free to use. No registration or personal data storage is required.