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Temperature Converter

Convert between Celsius (°C), Fahrenheit (°F) and Kelvin (K) with the exact offset formulas.

How temperature conversion works

Temperature is unlike every other category: the scales have different zero points, so converting needs a formula with an offset rather than a plain multiplication. Celsius and Kelvin share the same step size (K = °C + 273.15), while Fahrenheit degrees are smaller — °F = °C × 9/5 + 32.

ConversionFormula
°C to °F°F = °C × 9/5 + 32
°F to °C°C = (°F − 32) × 5/9
°C to KK = °C + 273.15
K to °C°C = K − 273.15
°F to KK = (°F − 32) × 5/9 + 273.15
K to °F°F = (K − 273.15) × 9/5 + 32

All temperature conversions

Every temperature pair has its own quick-reference page with a conversion table:

Back to the full unit converter for all seven categories.

Common mistakes to avoid

A quick accuracy check

Want to sanity-check any converter? Convert -40 from Celsius to Fahrenheit: the result must be exactly -40, the only temperature where the two scales meet. Then convert 0 Kelvin to Celsius: you should get -273.15, absolute zero. A converter that handles both edge cases correctly has sound temperature formulas, and this one does.

Frequently asked questions

What is the formula for Celsius to Fahrenheit?

Multiply by 9/5 and add 32: °F = °C × 9/5 + 32. Going back: °C = (°F − 32) × 5/9. Kelvin only shifts the zero point: K = °C + 273.15.

At what temperature do Celsius and Fahrenheit meet?

−40 °C equals −40 °F — the only point where the two scales read the same. It makes a good sanity check for any temperature converter.