How to convert celsius to fahrenheit
Useful for weather, cooking, HVAC, science communication, and international travel. Temperature requires both a scale ratio and a zero-point offset, applied in the correct order.
°F = (°C × 9/5) + 32
Worked example: 25 °C = 77 °F.
Celsius to Fahrenheit reference table
| °C | °F |
|---|---|
| -40 | -40 |
| 0 | 32 |
| 20 | 68 |
| 37 | 98.6 |
| 100 | 212 |
Absolute zero
CalcOS rejects thermodynamic temperatures below 0 K: −273.15 °C or −459.67 °F. This physical boundary is enforced regardless of the selected display scale.
Temperature versus temperature difference
The offsets in the formulas above apply to absolute readings. For intervals, a change of 1 °C equals 1 K, and a change of 1 °F equals 5/9 K; the +32 offset is not applied.
Related temperature conversion
Sources: BIPM SI Brochure and NIST Handbook 44, Appendix C. See the complete Temperature Converter guide.