Celsius to Fahrenheit

Convert temperatures between Celsius and Fahrenheit instantly. Includes formula explanation and common temperature reference points.

How it works

°F = (°C × 9/5) + 32. °C = (°F − 32) × 5/9. K = °C + 273.15. The scales meet at −40°.

Worked example

20°C × 1.8 + 32 = 68°F. Reversing, 98.6°F − 32 = 66.6, × 5/9 = 37°C — normal body temperature.

Frequently asked questions

What is the quick mental conversion?

Double the Celsius figure and add 30. 20°C → 70°F estimated versus 68°F actual — accurate enough for weather within the everyday range.

Which reference points should I memorise?

0°C = 32°F (freezing), 37°C = 98.6°F (body), 100°C = 212°F (boiling), and −40 is the same in both scales.

Why is the formula not a simple multiplication?

The scales have different zero points as well as different degree sizes, so conversion needs both a factor of 9/5 and a 32-degree offset.