The conversion
5°F = −15°C
°C = (°F − 32) × 5/9, so (5 − 32) × 5/9 = −15.
As an outdoor air temperature, 5 °F sits in the bitter band. The other scale is on the dial beside it in the app, so a reading like this needs no conversion at all.
Convert something else
68°F
The range either side
Neighbouring values, for when the number you actually wanted was a degree or two away.
| Fahrenheit | Celsius |
|---|---|
| 0 °F | −17.78 °C |
| 1 °F | −17.22 °C |
| 2 °F | −16.67 °C |
| 3 °F | −16.11 °C |
| 4 °F | −15.56 °C |
| 5 °F | −15 °C |
| 6 °F | −14.44 °C |
| 7 °F | −13.89 °C |
| 8 °F | −13.33 °C |
| 9 °F | −12.78 °C |
| 10 °F | −12.22 °C |
The other direction
−15 °C converts back to 5 °F, which is the same relationship read the other way. Going from Celsius to Fahrenheit, multiply by 9/5 first and then add 32. Adding first is the usual mistake.
The full converter handles any value, in either direction, including kelvin, and shows the formula as it works.