What is the formula for Celsius to Kelvin?

Add 273.15 to the Celsius value. K = °C + 273.15. For example, 0°C (water freezing) = 273.15 K, and 100°C (water boiling) = 373.15 K.

Why does the Kelvin scale start at absolute zero?

Kelvin is defined starting at absolute zero (-273.15°C), the theoretical minimum temperature where all thermal motion ceases. This makes Kelvin ideal for physics equations that require a true zero.

Does Kelvin use the degree symbol?

No. Temperatures in Kelvin are written as K (not °K). You write 300 K, not 300 °K.

Convert Celsius to Kelvin Online

Kelvin is the SI base unit for temperature and is essential in scientific, physics, chemistry, and engineering contexts. Unlike Celsius and Fahrenheit, Kelvin is an absolute temperature scale with no negative values — absolute zero (0 K) is the lowest possible temperature, where all molecular motion stops. Converting from Celsius to Kelvin uses the simple formula K = °C + 273.15. This tool performs the conversion instantly for any Celsius temperature. Scientists use Kelvin when working with thermodynamic equations, gas laws, black body radiation, and any calculation where the zero point matters mathematically. The converter also works for converting Kelvin back to Celsius by subtracting 273.15.

Temperature

Unit

Celsius (°C)

100°C

Fahrenheit (°F)

212°F

Kelvin (K)

373.15K

FAQ

What is the formula for Celsius to Kelvin?: Add 273.15 to the Celsius value. K = °C + 273.15. For example, 0°C (water freezing) = 273.15 K, and 100°C (water boiling) = 373.15 K.
Why does the Kelvin scale start at absolute zero?: Kelvin is defined starting at absolute zero (-273.15°C), the theoretical minimum temperature where all thermal motion ceases. This makes Kelvin ideal for physics equations that require a true zero.
Does Kelvin use the degree symbol?: No. Temperatures in Kelvin are written as K (not °K). You write 300 K, not 300 °K.

Related Conversions

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