Oven temperature converter

Fahrenheit, Celsius, gas mark and the fan-oven adjustment.

Fahrenheit
350 °F
Celsius
177 °C
Gas mark
4
Fan / convection
155 °C · 325 °F

Roughly 20 °C lower

Oven temperature chart

°F°CFan °CGasDescription
22510585¼Very cool
250120100½Very cool
2751351151Cool
3001501302Cool
3251651453Warm
3501751554Moderate
3751901705Moderate
4002051856Moderately hot
4252202007Hot
4502302108Hot
4752452259Very hot
50026024010Very hot

How it works

Oven conversions are just temperature conversions, with two wrinkles: gas marks, and fans.

°C = (°F − 32) × 5/9 gas mark = (°F − 275) ÷ 25 + 1

Gas marks

The UK gas mark scale starts at mark 1 = 275 °F and adds 25 °F per mark, with fractional marks ¼ and ½ below it for very slow cooking. It is a coarse scale on purpose — gas ovens swing far more than the numbers suggest.

Rounding is fine here

Recipes are written in round numbers because domestic ovens are routinely 10–15 °C off and cycle around their setpoint. 350 °F converts to 176.7 °C, but every European recipe writes 180. An oven thermometer tells you more than another decimal place ever will.

Altitude

Above about 3,000 ft, lower pressure means water boils cooler and leavening expands faster. The usual adjustment is to raise the oven by 15–25 °F and shorten the bake slightly, plus a little extra liquid.