Kelvin to Celsius (K to °C) Converter
A complete temperature conversion tool. Enter a value in any field to instantly convert between **Kelvin (K)**, **Celsius (°C)**, and **Fahrenheit (°F)**.
Calculation Steps:
Enter a value to see the step-by-step conversion.
How to Convert Kelvin to Celsius
The conversion from Kelvin (K) to Celsius (°C) is the simplest temperature conversion because the *size* of one kelvin is identical to the size of one degree Celsius. The only difference is their starting point.
The Formula (Kelvin to Celsius)
To convert from Kelvin to Celsius, you simply subtract 273.15.
Example: Convert the boiling point of water (373.15 K) to Celsius.
373.15 K - 273.15 = 100 °C
The Formula (Celsius to Kelvin)
To convert from Celsius to Kelvin, you add 273.15.
What is Absolute Zero?
The Kelvin scale is an "absolute" scale, meaning its zero point (0 K) is **Absolute Zero**. This is the theoretical temperature at which all atomic and molecular motion ceases. There is no temperature colder than 0 K, which is why the Kelvin scale has no negative numbers. Celsius and Fahrenheit are "relative" scales, as their zero points (0°C and 0°F) were set for convenience (e.g., the freezing point of water).
Key Temperature Points
| Point | Kelvin (K) | Celsius (°C) | Fahrenheit (°F) |
|---|---|---|---|
| Absolute Zero | 0 K | -273.15 °C | -459.67 °F |
| Water Freezes | 273.15 K | 0 °C | 32 °F |
| Human Body (Avg) | 310.15 K | 37 °C | 98.6 °F |
| Water Boils | 373.15 K | 100 °C | 212 °F |
Frequently Asked Questions (FAQ)
What is the formula for Kelvin (K) to Celsius (°C)?
The formula is: Celsius = Kelvin - 273.15. (C = K - 273.15).
What is 0 Kelvin in Celsius?
0 Kelvin (K) is equal to -273.15 °C. This is known as Absolute Zero.
What is 0 Celsius in Kelvin?
0 °C (the freezing point of water) is equal to 273.15 K.
Formula (LaTeX) + variables + units
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- NIST — Weights and measures — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/weights-and-measures - NIST — SI units — nist.gov · Accessed 2026-01-19
https://www.nist.gov/pml/owm/metric-si/si-units
Last code update: 2026-01-19
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