Convert degrees Fahrenheit to degrees Celsius
Enter any value to calculate the result instantly.
degrees Fahrenheit to degrees Celsius formula
Subtract 32 from the Fahrenheit value, then multiply by 5/9. Subtracting the offset before scaling is essential.
Conversion table
Use these reference values for a quick comparison. The calculator above accepts positive, negative, decimal, and large values when they are meaningful for the quantity.
| degrees Fahrenheit | degrees Celsius |
|---|---|
| -40 F | -40 C |
| 32 F | 1.400000e-9 C |
| 50 F | 10 C |
| 68 F | 20 C |
| 98.6 F | 37 C |
| 212 F | 100 C |
How to use this converter
Enter the source measurement in the first field. CalUnit applies the displayed formula and updates the destination value immediately. You can use decimals and negative values, copy the result into your work, and compare it with the reference table. Keep the original unit beside the starting measurement so another reader can verify the calculation. For a different unit pair, open the complete temperature conversion guide or the multi-unit temperature converter.
When this conversion is useful
This conversion helps compare US weather reports and oven settings with metric references. Negative values are handled by the same formula.
Accuracy and rounding
The scale relationship is exact. Round weather values to a useful whole or tenth degree rather than displaying unnecessary decimals.
Standards references
CalUnit checks physical unit relationships against authoritative measurement references. See the NIST Guide to the SI conversion factors and the BIPM SI Brochure. Regional cooking measures and digital storage conventions are identified separately because their names can represent more than one definition.