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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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Page guide

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 °F0 °C
40 °F4.44 °C
50 °F10 °C
60 °F15.56 °C
65 °F18.33 °C
70 °F21.11 °C
72 °F22.22 °C
75 °F23.89 °C
80 °F26.67 °C
90 °F32.22 °C
98.6 °F37 °C
100 °F37.78 °C
212 °F100 °C
300 °F148.89 °C
350 °F176.67 °C
400 °F204.44 °C
450 °F232.22 °C

Values are rounded to 2 decimal places.

How to use Fahrenheit to celsius
  1. Enter the values you want to calculate and choose the relevant units or settings.
  2. The result updates as you type. Adjust the available settings if needed.
  3. 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.