Temperature Converter: Celsius, Fahrenheit and Kelvin
Convert Celsius to Fahrenheit, Fahrenheit to Celsius and Kelvin in one box. Type a temperature in any of the three fields and the others update as you type, with the formula shown so you can do it yourself next time.
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Quick answer: To convert Celsius to Fahrenheit, multiply by 9/5 (1.8) and add 32. So 25 °C × 1.8 + 32 = 77 °F. To go from Fahrenheit to Celsius, subtract 32 and multiply by 5/9: 77 °F − 32 = 45, × 5/9 = 25 °C.
Celsius to Fahrenheit formulas
- °C to °F: °F = °C × 9/5 + 32
- °F to °C: °C = (°F − 32) × 5/9
- °C to K: K = °C + 273.15
- Quick mental estimate: double the Celsius and add 30. 20 °C gives about 70 °F (exact: 68 °F). It is close for everyday weather.
Celsius to Fahrenheit chart
| °C | °F | What it feels like |
|---|---|---|
| −40 | −40 | The point where both scales are equal |
| −18 | 0 | Freezer |
| 0 | 32 | Water freezes |
| 10 | 50 | Cool day |
| 20 | 68 | Room temperature |
| 30 | 86 | Hot day |
| 37 | 98.6 | Normal body temperature |
| 40 | 104 | Heatwave; high fever |
| 100 | 212 | Water boils at sea level |
Oven temperatures
| °C | °F | Gas mark |
|---|---|---|
| 150 | 300 | 2 |
| 160 | 325 | 3 |
| 180 | 350 | 4 |
| 190 | 375 | 5 |
| 200 | 400 | 6 |
| 220 | 425 | 7 |
Recipes round oven temperatures, so 180 °C and 350 °F are treated as the same setting even though 350 °F is exactly 176.7 °C. For fan ovens, many recipes suggest about 20 °C lower.
Who uses which scale?
The United States and a few other places use Fahrenheit for weather and cooking. Almost everywhere else, including India, the UK and Europe, uses Celsius. Scientists use Kelvin, which starts at absolute zero, the coldest possible temperature (0 K = −273.15 °C).
Converting other units? Try the length converter or the weight converter.
FAQ
Is 37 °C a fever?
No, 37 °C (98.6 °F) is the average normal body temperature. A fever usually starts around 38 °C (100.4 °F).
What is 0 °F in Celsius?
About −17.8 °C.
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