Temperature calculator
Fahrenheit to Celsius Converter
Convert fahrenheit (f) to celsius (c) with the exact temperature formula, worked examples, and a common-values table.
Exact conversion
Fahrenheit to celsius formula
c = (f × 0.555555556) − 17.7777778
1 f equals -17.2222222 c. 10 f equals -12.2222222 c.
About these units
- f
- Degrees Fahrenheit.
- c
- Degrees Celsius.
Before you use the result
f to c context and checks
- Best use
- Use temperature conversions for weather, cooking, lab notes, HVAC, and equipment settings.
- Common mistake
- Temperature scales use offsets, so Celsius to Fahrenheit is not only multiplication. Temperature differences use different handling.
- Precision note
- Avoid rounding before applying an offset formula because the zero point and interval size both affect the result.
Example check: -40 f converts to -40 c. Use this known value to sanity-check a spreadsheet, homework solution, spec sheet, or manual calculation.
Common f to c conversion table
| f | c |
|---|---|
| -40 f | -40 c |
| 0 f | -17.7777778 c |
| 20 f | -6.66666667 c |
| 100 f | 37.7777778 c |
FAQ8 common questions for this calculator.
FAQs
How do I convert fahrenheit to celsius?+
Use this formula: c = (f × 0.555555556) − 17.7777778. Enter the f value and the calculator applies the relationship immediately.
How many c are in 1 f?+
1 f equals -17.2222222 c.
What is 10 f in c?+
10 f equals -12.2222222 c. The displayed result may be rounded, while the calculator keeps full precision internally.
Can I convert celsius back to fahrenheit?+
Yes. Use Swap in the converter to reverse the units and calculate c to f.
How does the Fahrenheit to Celsius Converter calculate the result?+
For the Fahrenheit to Celsius Converter, it uses the Fahrenheit to celsius formula: c = (f × 0.555555556) − 17.7777778. 1 f equals -17.2222222 c. 10 f equals -12.2222222 c.
What information do I need to use the Fahrenheit to Celsius Converter?+
Enter the values requested by the form, keep units consistent, and use the displayed assumptions to decide whether the Fahrenheit to Celsius Converter matches your scenario.
How accurate is the Fahrenheit to Celsius Converter?+
Fahrenheit to Celsius Converter is accurate for the values and assumptions entered on this page. It uses the Fahrenheit to celsius formula. Recheck the inputs before relying on the estimate.
What should I check before using the Fahrenheit to Celsius Converter result?+
For the Fahrenheit to Celsius Converter, check that the units, inputs, and assumptions match your situation. Change one input at a time to understand which values have the largest effect on the result.
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How to use the Fahrenheit to Celsius Converter
Convert fahrenheit (f) to celsius (c) with the exact temperature formula, worked examples, and a common-values table. Use the instant result for the fahrenheit to celsius conversion, then check the common-value table, reverse link, and unit notes before copying the answer.
- 1
Enter Fahrenheit
Type the fahrenheit value you want to convert. Decimal values work when you need a partial unit.
- 2
Read Celsius
Use the main result for the exact celsius value, then scan the common-value table for nearby reference points.
- 3
Confirm Fahrenheit to Celsius
Confirm the fahrenheit to celsius unit symbols before using the number in a report, product listing, invoice, or assignment.