Fahrenheit to Celsius Converter
Convert Fahrenheit to Celsius instantly. The order matters here: subtract 32 first, then scale, because the two scales have different zero points as well as different degree sizes.
Enter a temperature below and the answer updates as you type. The formula, a reference chart and common questions follow.
Fahrenheit to Celsius converter
degrees Fahrenheit (°F)= degrees Celsius (°C)The formula
(°F − 32) × 5/9 = °C. Five ninths is about 0.5556, so you can also subtract 32 and then divide by 1.8.
Subtracting 32 removes the offset between the scales, since water freezes at 32 °F but at 0 °C. Only then does the multiplication by five ninths convert the size of the degree, because a Fahrenheit degree is smaller than a Celsius one.
Doing it the other way round is the classic mistake and gives an answer roughly eighteen degrees out. As a rough check for weather, subtract 30 and halve: 70 °F becomes 40, then 20 °C, against a true figure of 21.1 °C.
Fahrenheit to Celsius chart
| Fahrenheit | Celsius | Reference |
|---|---|---|
| −40 °F | −40 °C | Scales coincide |
| 0 °F | −17.8 °C | Severe cold |
| 32 °F | 0 °C | Water freezes |
| 50 °F | 10 °C | Cool spring day |
| 68 °F | 20 °C | Room temperature |
| 77 °F | 25 °C | Warm summer day |
| 86 °F | 30 °C | Hot summer day |
| 98.6 °F | 37 °C | Body temperature |
| 212 °F | 100 °C | Water boils |
Frequently asked questions
What is 100 degrees Fahrenheit in Celsius?
One hundred degrees Fahrenheit is 37.8 degrees Celsius: 100 minus 32 is 68, and 68 multiplied by five ninths is 37.8.
What is 350 °F in Celsius for baking?
350 °F is 177 °C, which British recipes round to 180 °C, or about 160 °C in a fan oven.
Why subtract 32 first?
Because the scales do not share a zero. Removing the 32 degree offset before scaling is what makes the arithmetic correct.
What is a normal body temperature in Celsius?
98.6 °F is 37 °C, though healthy readings range from roughly 36.1 to 37.2 °C depending on the person and time of day.
Is there a quick mental method?
Subtract 30 and then halve. For 80 °F that gives 25 °C against a true 26.7, close enough for a forecast.
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