Fahrenheit to Celsius Converter
Convert fahrenheit (°F) to celsius (°C) instantly, with the exact conversion factor and a table of common values.
How it works
Fahrenheit and celsius are both units of temperature, so converting between them is a single multiplication by a fixed factor — there is no rounding rule or regional variation to worry about.
The factor used here is exact: 1 °F is defined as — °C. Results are shown to enough decimal places to stay useful for small values without turning large ones into noise.
The formula
Fahrenheit → Celsius
°C = °F × factor
Celsius → Fahrenheit
°F = °C ÷ factor
Worked examples
| Scenario | Working | Result |
|---|---|---|
| -40 °F | -40 °F | -40 °C |
| 0 °F | 0 °F | -17.7778 °C |
| 32 °F | 32 °F | 0 °C |
| 50 °F | 50 °F | 10 °C |
When you'd use it
- Reading a recipe, spec sheet or label written in the other system
- Filling in a form that expects a specific unit
- Checking luggage, shipping or equipment limits
- Coursework and lab reports that require SI units
Common questions
How many celsius are in a fahrenheit?
One fahrenheit equals — celsius. Multiply by that number to convert, or divide by it to go the other way.
Is the conversion exact?
The factor is exact by definition — these units are defined in terms of each other. Only the display is rounded, and you can copy the full-precision result.
Why does my answer differ slightly from another converter?
Almost always rounding. Some converters round the factor itself before multiplying, which compounds the error on large values. This one multiplies first and rounds only for display.