Temperature Converter

Convert Celsius, Fahrenheit, Kelvin, and Rankine — instantly, as you type.

Quick fill:
°C Celsius
°F Fahrenheit
K Kelvin
°R Rankine

Temperature Conversion Formulas

All conversions are performed via Celsius as the base unit. Below are the standard formulas used by this tool.

How do I convert Celsius to Fahrenheit?

Multiply by 9/5, then add 32: °F = (°C × 9/5) + 32. Example: 100°C → 212°F (water's boiling point at sea level).

How do I convert Celsius to Kelvin?

Add 273.15 to the Celsius value: K = °C + 273.15. Kelvin is the SI unit for thermodynamic temperature and starts at absolute zero — there are no negative Kelvin values.

What temperature is the same in Celsius and Fahrenheit?

At −40°, both scales read the same value. This is because the two formulas intersect at that exact point — a useful sanity-check when doing manual conversions.

What is absolute zero in Celsius and Fahrenheit?

Absolute zero is 0 K = −273.15°C = −459.67°F. The Rankine scale also starts at absolute zero but uses Fahrenheit-sized degrees, so 0°R = 0 K.