The conversion

800°F = 426.67°C

°C = (°F − 32) × 5/9, so (800 − 32) × 5/9 = 426.67.

800 °F is well outside the range outdoor air occupies on Earth, so there is no useful weather description for it — this page is arithmetic rather than a forecast.

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 to Celsius either side of 800 °F.
FahrenheitCelsius
795 °F423.89 °C
796 °F424.44 °C
797 °F425 °C
798 °F425.56 °C
799 °F426.11 °C
800 °F426.67 °C
801 °F427.22 °C
802 °F427.78 °C
803 °F428.33 °C
804 °F428.89 °C
805 °F429.44 °C

The other direction

426.67 °C converts back to 800 °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.