Convert between UK gas marks and °C/°F — and between a conventional oven setting and the (usually 20°C / 25°F lower) fan-assisted setting for the same result.
| Gas mark | °C | °F | Description |
|---|
Fan ovens are conventionally set about 20°C (25°F) cooler for the same result — some manufacturers say 10% cooler instead. Check your oven's manual if it states otherwise.
A UK oven temperature scale used mainly for gas ovens and in British recipes, running roughly from ¼ (very cool) to 9 (very hot). It doesn't convert to °C by a formula — it's a published lookup table, reproduced above.
A fan circulates hot air around the food, transferring heat faster and more evenly than a conventional oven relying on natural convection. Recipes written for conventional ovens are typically adjusted down by about 20°C (25°F) — or the cooking time is shortened instead — when using a fan setting.
No — it's the standard published convention. Real ovens vary by several degrees from their dial setting, and manufacturers don't all use the same fan offset. An oven thermometer is the only way to check your specific oven.
