ConvBolt — Unit ConverterDegrees Fahrenheit to Degrees Celsius Converter
Converting degrees Fahrenheit to degrees Celsius is a multiplication by a fixed factor: 1 °F = -17.22222 °C. The table below covers the values people look up most often, and the formula section shows exactly where that factor comes from.
Weather, cooking and lab work are the three everyday sources: a forecast written in degrees Fahrenheit against a thermostat set in degrees Celsius, and a lab protocol that fixes a point on one scale while a log records the other.
Kelvin and the degree scales differ by an offset, not a ratio: -17.77778 °C corresponds to 0 °F, so the arithmetic is a shift plus a scale step. That offset is also why a small rounding error in fahrenheit can look alarming once it is restated in celsius — the number you see is the sum of two operations, not one.
Degrees Fahrenheit to Degrees Celsius formula
Use this formula to convert any fahrenheit value to degrees Celsius:
Worked example: 100 °F × -17.22222 = 37.77778 °C.
Degrees Fahrenheit to Degrees Celsius conversion table
| Degrees Fahrenheit (°F) | Degrees Celsius (°C) |
|---|---|
| -40 °F | -40 °C |
| 0 °F | -17.77778 °C |
| 10 °F | -12.22222 °C |
| 20 °F | -6.666667 °C |
| 30 °F | -1.111111 °C |
| 37 °F | 2.777778 °C |
| 50 °F | 10 °C |
| 100 °F | 37.77778 °C |
| 150 °F | 65.55556 °C |
| 200 °F | 93.33333 °C |
| 300 °F | 148.8889 °C |
How to convert degrees Fahrenheit to degrees Celsius
Multiply the fahrenheit value by -17.22222 to get the equivalent in degrees Celsius. This single factor works for every value in the table above and for anything else you need — there is no per-value adjustment, which is why a conversion table and a calculator always agree.
If you need the opposite direction, use the Degrees Celsius to Degrees Fahrenheit converter instead of dividing by hand; both pages use the same source factors. For every other °F conversion in one place, see the °F conversion hub.
Frequently asked questions
How many degrees Celsius are in 1 fahrenheit?
1 fahrenheit = -17.22222 °C.
What is 100 degrees Fahrenheit in degrees Celsius?
100 °F = 37.77778 °C.
Is converting degrees Fahrenheit to degrees Celsius the same as degrees Celsius to degrees Fahrenheit?
No — the direction changes the multiplier. The reverse conversion (1 °C = 33.8 °F) is on the Degrees Celsius to Degrees Fahrenheit page.
Related conversions
Try the ConvBolt Unit Converter for any other temperature unit, browse the Temperature conversions, or read our conversion guides.