How-to guides · 3 min read
How to Convert Celsius to Fahrenheit (and Back) Fast
Celsius to Fahrenheit
Multiply by 1.8 (that is 9/5), then add 32.
25 °C in °F
Step-by-step working 2 steps
- 1Convert to Celsius first
25 °C
- 2Convert Celsius to °F
25 × 9/5 + 32 = 77 °F
Fahrenheit to Celsius
Subtract 32, then multiply by 5/9.
98.6 °F in °C
Step-by-step working 2 steps
- 1Convert to Celsius first
(98.6 − 32) × 5/9 = 37 °C
- 2Convert Celsius to °C
37 °C
A mental shortcut
Double the Celsius value and add 30. For 20 °C: 40 + 30 = 70 °F; the exact answer is 68. Good for weather, not for baking or science.
Handy reference points
| Situation | °C | °F |
|---|---|---|
| Water freezes | 0 | 32 |
| Comfortable room | 20 | 68 |
| Body temperature | 37 | 98.6 |
| Water boils (sea level) | 100 | 212 |
More values in the temperature conversion chart; other units in the unit converter.
Frequently asked questions
What is 0 °C in Fahrenheit?
32 °F.
Why add 32?
The two scales have different zero points: Fahrenheit’s 0 is 32 degrees below the freezing point of water.
Keep reading
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