# Celsius to Kelvin (°C to K)

Source: https://www.unitconvertercalculator.com/temperature/celsius-to-kelvin/

To convert Celsius to kelvin, simply add 273.15. This is the simplest temperature conversion because both scales use the same degree size - they differ only in their zero point. Kelvin is essential in science, while Celsius dominates everyday life in most countries.

## Formula

K = °C + 273.15

## Conversion Table

| Celsius (°C) | Kelvin (K) |
|---|---|
| -40 °C | 233.15 K |
| -20 °C | 253.15 K |
| -10 °C | 263.15 K |
| 0 °C | 273.15 K |
| 5 °C | 278.15 K |
| 10 °C | 283.15 K |
| 15 °C | 288.15 K |
| 20 °C | 293.15 K |
| 25 °C | 298.15 K |
| 30 °C | 303.15 K |
| 36 °C | 309.15 K |
| 37 °C | 310.15 K |
| 40 °C | 313.15 K |
| 50 °C | 323.15 K |
| 60 °C | 333.15 K |
| 80 °C | 353.15 K |
| 100 °C | 373.15 K |
| 150 °C | 423.15 K |
| 180 °C | 453.15 K |
| 200 °C | 473.15 K |
| 220 °C | 493.15 K |
| 250 °C | 523.15 K |
| 300 °C | 573.15 K |
| 500 °C | 773.15 K |
| 1000 °C | 1273.15 K |

## Units

### Celsius (°C)

A metric temperature scale where 0°C is the freezing point and 100°C is the boiling point of water. Used worldwide except in the US.

### Kelvin (K)

The SI base unit of temperature. 0 K is absolute zero, the theoretical lowest possible temperature. Used in science and engineering.

## Background

Room temperature of 20°C is 293.15 K. Water boils at 373.15 K (100°C) and freezes at 273.15 K (0°C). Scientists use kelvin for thermodynamic calculations, gas law equations, and expressing color temperature. When a recipe says 180°C and a physics formula needs kelvin, just add 273.15.

## Good to Know

In everyday life, nobody uses kelvin - it's purely for science and engineering. But in physics classrooms worldwide, the conversion from Celsius to kelvin is one of the first things students learn.

## FAQ

### How do I convert Celsius to kelvin?

Add 273.15 to the Celsius temperature. For example, 25°C + 273.15 = 298.15 K. This is an exact offset - no multiplication needed because both scales have identical degree sizes.

### Why is there no degree symbol for kelvin?

The kelvin is an SI base unit, not a degree-based scale. Since 1967, it is written as simply 'K' without a degree symbol, unlike °C or °F. Writing '°K' is incorrect.

### What is 0°C in kelvin?

0°C equals exactly 273.15 K. This is the freezing point of water at standard pressure and the offset between the two scales.

## Non-Frequently Asked Questions

### Is Lord Kelvin related to the Kelvin Klein fashion brand?

It is Calvin Klein, not Kelvin Klein. Lord Kelvin (William Thomson) was a physicist who worked on thermodynamics. Calvin Klein makes underwear. Both are famous, but for very different contributions to human comfort.

### Can I get negative Kelvin?

In classical thermodynamics, no. Kelvin starts at absolute zero (0 K = minus 273.15 degrees Celsius) and only goes up. Some quantum physicists have argued about negative temperatures in exotic systems, but your freezer will never show minus 5 Kelvin.

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## See Also

- [Kelvin to Celsius](https://www.unitconvertercalculator.com/temperature/kelvin-to-celsius/)