What is the Kelvin to Celsius Converter?
This tool converts a temperature on the Kelvin (K) absolute scale into degrees Celsius (°C). The Kelvin scale starts at absolute zero, the coldest possible temperature, where 0 K equals -273.15 °C. Because both scales use the exact same degree size, converting between them only requires shifting by a fixed offset — no scaling or multiplication is involved.
How to use it
Enter your temperature in Kelvin and press calculate. The converter returns the equivalent value in degrees Celsius along with a step-by-step worked solution. The default value is 300 K, roughly normal room temperature. The Kelvin scale has no negative values, so if you enter a number below 0 the tool still computes the result but flags it as physically impossible.
The formula explained
The conversion is: $$^{\circ}\text{C} = \text{K} - 273.15$$ The constant 273.15 is exact by definition and represents the difference between the zero points of the two scales. Useful reference points: absolute zero is \(0\ \text{K} = -273.15\ {}^{\circ}\text{C}\), water freezes at \(273.15\ \text{K} = 0\ {}^{\circ}\text{C}\), and water boils at \(373.15\ \text{K} = 100\ {}^{\circ}\text{C}\).
Worked example
Convert 300 K to Celsius: $$^{\circ}\text{C} = 300 - 273.15 = 26.85\ {}^{\circ}\text{C}$$ So 300 K equals 26.85 °C, a comfortable room temperature. Another example: \(0\ \text{K} = 0 - 273.15 = -273.15\ {}^{\circ}\text{C}\), which is absolute zero.
FAQ
Why subtract 273.15 and not 273? The precise offset between Kelvin and Celsius is exactly 273.15 by international definition. Using 273 introduces a 0.15 degree error.
Can Kelvin be negative? No. 0 K is absolute zero, the lowest possible temperature, so genuine Kelvin readings are always at or above zero.
Is a 1 K change the same as a 1 °C change? Yes. The two scales share identical degree intervals; only their starting points differ.
