Oven Temperature Converter

Enter an oven temperature from a recipe in Fahrenheit, Celsius, a fan (convection) setting or a gas mark, and the converter gives the equivalent in every other system, plus the traditional description such as moderate or hot. It is designed for cooking, so it rounds to the steps used on oven dials, and shows the exact figure too. A scale marks the temperature against the gas marks and the matching fan setting.

°F = °C × 9 ÷ 5 + 32    °C = (°F − 32) × 5 ÷ 9

fan °C ≈ conventional °C − 20

The Celsius to Fahrenheit formula is exact, so 180 °C is 356 °F and 350 °F is 176.7 °C. Recipes and dials round these to convenient steps, which is why 180 °C and 350 °F are treated as the same moderate oven. Gas marks are a scale used on British gas cookers, with each mark roughly 10 to 15 °C apart.

A fan oven circulates hot air, which transfers heat to food faster than still air, so recipes written for a conventional oven usually need a lower setting. Consumer testers such as Which? advise reducing the temperature by about 20 °C; in Fahrenheit the usual advice is about 25 °F. Some newer ovens apply this adjustment automatically on their convection setting, so check your manual. Many British recipes now give both figures, for example 200 °C or 180 °C fan.

Older cookbooks often describe the oven instead of giving a number. A slow or cool oven is roughly 140 to 150 °C, a moderate oven about 180 °C, a hot oven around 200 to 220 °C and a very hot oven 230 °C or more. These descriptions varied between books and countries, so treat them as a range and watch the food, especially for cakes and pastry that depend on the right heat.

1. Choose what the recipe gives: Fahrenheit, Celsius, a fan setting or a gas mark.
2. Enter the temperature, or pick the gas mark from the list.
3. Read the setting for your oven. Use the fan figure if your oven circulates air and does not adjust automatically.

Air fryers are small, powerful convection ovens. A common starting point is to use the fan oven temperature, or to reduce a conventional recipe by about 20 °C, and to shorten the cooking time, checking the food early because the small cavity heats quickly. Manufacturers' guides differ, so follow the instructions for your model where they exist. Toaster ovens without a fan generally follow conventional oven temperatures but may brown food faster because the elements are close to it.

Above about 3,000 feet, water boils at a lower temperature and doughs rise faster, so many high-altitude baking guides suggest raising the oven temperature by 15 to 25 °F and shortening the baking time, along with changes to leavening and liquid. Check a guide from your state extension service for tested adjustments.

• Oven thermostats are often off by 10 °C or more. An oven thermometer on the middle shelf shows the real temperature.
• Preheat fully before baking; many ovens signal they are ready before the whole cavity has reached temperature.
• Opening the door drops the temperature quickly, so check food through the window where you can.
• Dark metal pans brown faster than glass or light pans; some bakers lower the temperature slightly for dark pans.