Celsius to Fahrenheit Converter (°C to °F)

How to use this calculator: celsius to fahrenheit

1. 1Enter the value measured in celsius (°C).
2. 2Confirm the direction is Celsius (°C) to Fahrenheit (°F); reversing the units changes the factor or offset.
3. 3Apply °F = (°C × 9/5) + 32. The live converter performs this substitution as you type.
4. 4Read the answer in °F and keep only justified precision.

Conversion formula

Celsius and Fahrenheit use different zero points and different degree sizes. To convert, multiply the Celsius value by 9/5 and add 32. Water freezes at 0 °C (32 °F) and boils at 100 °C (212 °F).

Temperature scales use different degree sizes and zero points, so the equation needs a multiplier and an offset. Check 0 °C = 32 °F.

Worked conversion example: Celsius to Fahrenheit

1. Given: 25 °C
2. Substitute: °F = (25 × 9/5) + 32
3. Result: 25 °C = 77 °F

Accuracy checklist

The converter keeps extra precision internally. Report only the precision supported by the original measurement and follow the required rounding rule.

Direction check: a smaller unit usually gives a larger number; temperature is an exception.

Unit definitions and SI traceability: NIST Office of Weights and Measures — SI Units.