Fahrenheit to Celsius
Convert °F To °C
The result updates as you type
To (°C)
1 °F = -17.2222222222 °C
Conversion formula and examples
Calculation formula: °C ≈ °F × 0.5555555556 − 17.77777778
| Source value (°F) | Result (°C) |
|---|---|
| -40 | ≈ -40 |
| 0 | ≈ -17.77777778 |
| 20 | ≈ -6.666666667 |
| 100 | ≈ 37.77777778 |
Table values are rounded to 10 significant digits. Use the converter above for your own value.
About this tool
Convert fahrenheit to Celsius online. Enter a value, choose rounding and see the calculation formula and example conversion table.
Frequently asked questions
How do I convert Fahrenheit to Celsius?
Enter the source value in the first field and select Convert. The heading shows the conversion direction. Use the formula and examples on this page to check the result.
How do I round the result?
Auto mode displays up to 10 decimal places. To set the precision, enable rounding and choose 1 to 10 decimal places. The example table is rounded separately for readability.