How to Convert Celsius to Fahrenheit (°C to °F)
Temperature conversions help with American oven recipes in Fahrenheit, weather apps set to the wrong unit, and science homework that uses kelvin. This guide shows how to convert celsius into fahrenheit by hand, with examples and a quick-reference table.
The conversion
Temperature scales have different zero points, so you cannot use a single multiplier. Convert through kelvin: °C converted through kelvin: (((°C+273.15)-273.15)*9/5+32).
°C converted through kelvin: (((°C+273.15)-273.15)*9/5+32)
Worked examples
- 15 °C = 59 °F
- 32 °C = 89.6 °F
- 100 °C = 212 °F
Celsius to Fahrenheit table
| Celsius | Fahrenheit |
|---|---|
| -40 °C | -40 °F |
| -10 °C | 14 °F |
| 0 °C | 32 °F |
| 10 °C | 50 °F |
| 20 °C | 68 °F |
| 25 °C | 77 °F |
| 30 °C | 86 °F |
| 37 °C | 98.6 °F |
| 50 °C | 122 °F |
| 100 °C | 212 °F |
| 200 °C | 392 °F |
Common questions
Is °C to °F exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Fahrenheit to Celsius converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Dropping the units
A bare number without a unit is easy to misread later. Always write the unit with the result.
Multiplying when you should divide
Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.
Background
Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
For any value, use the Celsius to Fahrenheit Converter or browse all temperature converters.
Run your own numbers: Celsius to Fahrenheit Converter