Celsius to Fahrenheit
Convert Celsius to Fahrenheit in your browser. Temperature is an offset scale, not a simple multiple, so 0 °C is 32 °F rather than zero.
°F = °C × 1.8 + 32
NIST SP 811 (2008), Appendix B.8 — degree Fahrenheit (temperature) (°F) to degree Celsius (°C): t/°C = (t/°F − 32)/1.8
Temperature is the conversion that breaks naive converters, because the two scales do not share a zero. Every other unit on this site is a plain ratio: double the kilometers and you double the miles. Here you have to scale and then shift, which is why 0 °C is 32 °F and why the two scales cross at exactly −40.
How it is calculated
°F = °C × 1.8 + 32
The standard states the inverse, that °C equals (°F − 32) divided by 1.8, and this is that relation rearranged. Note that the offset applies to temperatures, not to differences: a rise of 1 °C is a rise of 1.8 °F, with no 32 involved.
Common values
| degrees Celsius | degrees Fahrenheit |
|---|---|
| -40 | -40 |
| -18 | -0.4 |
| 0 | 32 |
| 10 | 50 |
| 16 | 60.8 |
| 20 | 68 |
| 25 | 77 |
| 30 | 86 |
| 37 | 98.6 |
| 100 | 212 |
| 180 | 356 |
| 200 | 392 |
Questions people ask
- What is normal body temperature in Fahrenheit?
- 37 °C is 98.6 °F. The precision is misleading: the original measurement was 37 °C to two digits, so 98.6 suggests more accuracy than anyone actually measured.
- Where do the two scales meet?
- At −40. It is the only point where the number is the same in both, which makes it a quick sanity check for any converter you do not trust.
- Why not convert through kelvin?
- Because it costs accuracy. Going through kelvin subtracts 273.15 from a number close to 273.15, which throws away significant digits exactly around freezing point. This tool converts directly and lands on 32 °F for 0 °C without any floating point dust.
Related tools
Fahrenheit to Celsius
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