Fahrenheit to Celsius
Open Fahrenheit to Celsius on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.
Tool capabilities
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Convert temperatures from Fahrenheit to Celsius.
How to convert degrees Fahrenheit to degrees Celsius
0 °F = -17.78 °C. Water freezes at 32 °F (0 °C) and boils at 212 °F (100 °C) at sea level.
Formula: °C = (°F − 32) × 5/9
Examples
- 72 °F = 22.22 °C
- 98.6 °F = 37 °C
- 350 °F = 176.67 °C
°F to °C conversion table
| Degrees Fahrenheit (°F) | Degrees Celsius (°C) |
|---|---|
| -40 °F | -40 °C |
| -20 °F | -28.89 °C |
| 0 °F | -17.78 °C |
| 10 °F | -12.22 °C |
| 20 °F | -6.67 °C |
| 32 °F | 0 °C |
| 40 °F | 4.44 °C |
| 50 °F | 10 °C |
| 60 °F | 15.56 °C |
| 65 °F | 18.33 °C |
| 70 °F | 21.11 °C |
| 72 °F | 22.22 °C |
| 75 °F | 23.89 °C |
| 80 °F | 26.67 °C |
| 90 °F | 32.22 °C |
| 98.6 °F | 37 °C |
| 100 °F | 37.78 °C |
| 212 °F | 100 °C |
| 300 °F | 148.89 °C |
| 350 °F | 176.67 °C |
| 400 °F | 204.44 °C |
| 450 °F | 232.22 °C |
Values are rounded to 2 decimal places.
How to use Fahrenheit to celsius
- Enter the values you want to calculate and choose the relevant units or settings.
- The result updates as you type. Adjust the available settings if needed.
- Review the result, then use Copy result or a download link when available.
Useful next steps
How Fahrenheit to celsius works
This converter changes an absolute temperature from degrees Fahrenheit to degrees Celsius with the formula °C = (°F - 32) × 5/9. The answer updates as you type and is rounded to 12 significant digits, so 0 °F shows as -17.7777777778 °C. Anything below absolute zero, -459.67 °F, is rejected. It converts temperature readings, not temperature differences: a change of 18 °F is a change of 10 °C, while entering 18 here gives the reading -7.77777777778 °C.
Before you start
Make sure your number is a temperature reading rather than a rise or drop in temperature. Use a period for decimals, such as 98.6, because commas are not accepted.
A worked example
Entering 98.6 returns 37, and 350, a common oven setting, returns 176.666666667, or about 176.67 °C. Entering -40 returns -40, the one point where both scales match.
Continue your workflow: Length, Weight, Temperature.
Common questions
What is the formula to convert Fahrenheit to Celsius?
Subtract 32 from the Fahrenheit value, then multiply by 5/9. For 68 °F, (68 - 32) × 5/9 = 36 × 5/9 = 20 °C. To go the other way, multiply Celsius by 9/5 and add 32.
Is there a quick way to estimate it in my head?
Subtract 30 and halve the result. 68 °F gives 19, close to the exact 20 °C. The shortcut works for everyday weather but drifts at the extremes: 212 °F gives 91 instead of 100. Use the exact formula for cooking, medicine or science.
What is 98.6 °F in Celsius?
98.6 °F converts to exactly 37 °C, the traditional reference value for normal body temperature. Real readings vary between people and through the day. Another common reference, 100.4 °F, converts to 38 °C.
Can I use this to convert a temperature change?
Not directly. The formula includes an offset of 32 that only applies to readings. A difference needs just the 5/9 factor, so a rise of 9 °F is a rise of 5 °C. Entering 9 here would give -12.7777777778 °C, which is the reading for 9 °F, not the size of the change.
What is the lowest temperature I can convert?
Absolute zero, -459.67 °F, which converts to -273.15 °C. Nothing can be colder, so the tool rejects lower values with an error. At -40 the two scales meet, so -40 °F is also -40 °C.