Nearly all home cooks will recognize this moment. You’ve taken out a recipe that instructs you to set the oven to gas mark 6. The recipe may have come from an older British cookbook or from a page your mother bookmarked years ago. The absence of a gas mark dial in your oven is the issue. It features numbers in Celsius, a fan symbol, and a digital display. Let’s start frowning.
In a fan oven, gas mark 6 is 180°C. The short answer is that. However, it is worthwhile to understand the slightly longer answer because the reasoning behind it will prevent you from making a mess the next time a recipe gives you an unfamiliar setting.
Gas mark 6 in a traditional oven (gas or electric, no fan) is equivalent to 200°C, or 400°F if you’re using an American recipe. To get the same effect, fan ovens operate about 20°C colder. Thus, 200°C in a regular oven turns into 180°C in a fan. By constantly circulating hot air around the food, the fan cooks it faster and more evenly, requiring less heat to achieve the same results. It’s a useful distinction that really counts, particularly when baking.
Many home cooks may have spent years cooking at the incorrect temperature without fully understanding why things weren’t quite right. A slightly drier roast than anticipated. A more resilient sponge. When the oven is 20 degrees hotter than the recipe calls for, you get these kinds of outcomes precisely.
It’s also important to note that most British kitchens now come equipped with fan ovens. Even if your oven has a conventional setting, there’s a good chance it’s fan-assisted by default if you purchased it within the last ten or so years. The majority of contemporary recipes have subtly begun to take this into consideration; when a recipe mentions a temperature without further explanation, it is more likely to be referring to a fan oven. However, older cookbooks were written in a different time period. For many years, British cooking was written in gas marks, and some of those recipes are still used today because they are effective.
Oven Temperature Conversion Table — Gas Mark 6 and Full Scale
| Gas Mark | Fan Oven (°C) | Conventional (°C) | Fahrenheit (°F) | Heat Level |
|---|---|---|---|---|
| 1 | 120°C | 140°C | 275°F | Cool |
| 2 | 130°C | 150°C | 300°F | Cool |
| 3 | 140°C | 160°C | 325°F | Moderate |
| 4 | 160°C | 180°C | 350°F | Moderate |
| 5 | 170°C | 190°C | 375°F | Moderately Hot |
| 6 | 180°C | 200°C | 400°F | Moderately Hot |
| 7 | 200°C | 220°C | 425°F | Hot |
| 8 | 210°C | 230°C | 450°F | Very Hot |
| 9 | 220°C | 240°C | 475°F | Very Hot |
Gas Mark 6 At a Glance
| Setting | Temperature |
|---|---|
| Fan Oven | 180°C |
| Conventional Oven | 200°C |
| Fahrenheit | 400°F |
| Heat Description | Moderately Hot |
| Fan Reduction vs Conventional | −20°C |
Common Dishes Cooked at Gas Mark 6 (180°C Fan)
| Dish | Approx. Cooking Time | Notes |
|---|---|---|
| Roast Chicken (1.5kg) | 1 hr 20 mins | Rest 15 mins before carving |
| Victoria Sponge | 20–25 mins | Check with skewer at centre |
| Roast Vegetables | 35–45 mins | Turn halfway through |
| Shortcrust Pastry Tart | 25–30 mins | Blind bake first |
| Meatloaf | 55–65 mins | Cover with foil for first half |
| Lasagne | 40–50 mins | Until golden and bubbling |
| Banana Bread | 50–60 mins | Test with skewer before removing |
Gas mark 6 is firmly in the “moderately hot” range according to the conversion table that is widely accepted. Gas mark 5, or 170°C fan, is located beneath it and is used for foods that require a longer, more gentle cooking time. Above it, gas mark 7 reaches 200°C fan, which is where bread and crispy roast potatoes are found. Gas mark 6 is right in the middle; it’s hot enough to properly brown food without scorching the surface before the center has had time to cook through.
Oven accuracy seems to be overlooked more often than it should be. An oven that is set to 180°C may actually be operating at 140°C or closer to 220°C, according to testing conducted by consumer organizations. The guesswork is eliminated by placing a cheap oven thermometer inside the rack. It’s a minor habit worth developing, especially if you bake frequently and haven’t been pleased with the outcome.
For the practical question at hand, when the recipe specifies gas mark 6, set your fan oven to 180°C. This includes the majority of roasting establishments, traybakes, casseroles with lids removed for the last step, and numerous cakes. It’s a dependable and practical heat source. And you’ll know exactly where to look on the dial the next time an old recipe gives you a gas mark.
