When you need this conversion
British recipes that use gas marks, US recipes in Fahrenheit on a Celsius oven, and fan or convection ovens that need an adjustment.
Gas mark chart
- Gas ¼: 110 °C / 225 °F (very cool)
- Gas ½: 130 °C / 250 °F (very cool)
- Gas 1: 140 °C / 275 °F (cool)
- Gas 2: 150 °C / 300 °F (cool)
- Gas 3: 170 °C / 325 °F (moderate)
- Gas 4: 180 °C / 350 °F (moderate)
- Gas 5: 190 °C / 375 °F (moderately hot)
- Gas 6: 200 °C / 400 °F (hot)
- Gas 7: 220 °C / 425 °F (hot)
- Gas 8: 230 °C / 450 °F (very hot)
- Gas 9: 240 °C / 475 °F (very hot)
Why the numbers are rounded
The exact conversion of 350 °F is 176.67 °C, but ovens and recipes use 180 °C. The difference is smaller than the swing of most home oven thermostats. For exact conversions, use Fahrenheit to Celsius.
Common mistakes
Not adjusting for a fan oven. Following a conventional temperature in a fan oven can over-brown the outside before the middle is done.
Trusting the dial. Home ovens are often off by 10–20 °C. An oven thermometer shows the real temperature.
For other temperatures, use Celsius to Fahrenheit.