Celsius to Kelvin Converter

Convert Celsius to Kelvin Instantly

This converter changes Celsius (°C) into Kelvin (K) as you type. Unlike simple unit conversions, temperature scales have different zero points, so the calculation uses a formula rather than a single multiplier. Enter any value above, switch direction with the swap button, or pick another scale from the dropdowns to move between Celsius, Fahrenheit, Kelvin, and Rankine.

The Celsius to Kelvin Formula

The exact conversion formula is:

K = °C + 273.15

To convert back (Kelvin to Celsius):

°C = K − 273.15

Worked Examples

Common temperatures converted from Celsius to Kelvin:

• 0 °C = 273.15 K
• 25 °C = 298.15 K
• 37 °C = 310.15 K
• 100 °C = 373.15 K

Understanding the Celsius and Kelvin Scales

Celsius sets 0° at the freezing point of water and 100° at its boiling point, and is the everyday standard in most of the world. Fahrenheit places freezing at 32° and boiling at 212°, and is used mainly in the United States. Kelvin starts at absolute zero (−273.15 °C), the coldest temperature physically possible, and is the SI base unit used in science. Rankine is the Fahrenheit-sized equivalent of Kelvin. Because the scales differ in both their zero point and their step size, converting between them requires the formula above rather than a single factor.

Where This Conversion Is Used

• Weather — reading forecasts and temperatures reported on a different scale
• Cooking and baking — following oven temperatures from international recipes
• Science and engineering — converting laboratory and thermodynamic data
• Medical — interpreting body temperature and fever readings
• Travel — understanding the local climate when abroad

Frequently Asked Questions

What is 0 °C in K?

0 °C equals 273.15 K. Use the calculator above for any other value.

What is normal body temperature in K?

Normal human body temperature is about 37 °C, which is 98.6 °F and 310.15 K.

Why can't I just multiply by one number?

Temperature scales have different starting points, not just different step sizes. That offset means you need the full formula — adding or subtracting a constant as well as scaling — to convert correctly.

Does this work on mobile?

Yes. The converter runs in any browser on phone, tablet, or desktop with no app or sign-up needed.