Oven Temperature Conversions for Baking (°C, °F, Gas Marks & Fan)

Baking is the least forgiving kind of cooking, and temperature is where recipes quietly betray you. A cake recipe written for a conventional oven in Celsius, opened by someone with a fan oven that reads in the same units, can still go wrong — because the *number* being the same doesn't mean the *heat* is the same. Add gas marks and Fahrenheit into the mix and it's no wonder edges burn while middles stay raw. This guide lays out every relationship you need on one page.

The master conversion chart

Here are the temperatures baking actually happens at, lined up across all four systems. "Fan" is the conventional Celsius figure reduced by 20°C — the standard adjustment explained in the next section:

The fan-oven adjustment nobody explains

A fan (convection) oven circulates hot air, so it heats food faster and more evenly than a conventional oven at the same dial setting. If you follow a conventional recipe's temperature exactly in a fan oven, your bake runs effectively *hotter* — the outside sets and browns before the inside catches up. The fix is a simple rule:

• Reduce the temperature by about 20°C when converting a conventional-oven recipe to a fan oven (so conventional 180°C → fan 160°C).
• Or reduce the time by roughly 10–15% instead, if you'd rather keep the temperature — but for baking, dropping the temperature is usually the safer choice.
• Don't do both unless a recipe explicitly tells you to, or you'll end up underbaked.

To move a specific figure between Celsius and Fahrenheit precisely — say a recipe calls for an unusual 165°C and you have a Fahrenheit dial — drop it into the temperature converter, which gives the exact figure instead of forcing you to interpolate between chart rows.

The formula, for when you're between chart rows

The Celsius–Fahrenheit relationship is fixed, so you can always compute it yourself:

1. 1°C to °F: multiply by 9, divide by 5, add 32. So 180°C → (180 × 9 ÷ 5) + 32 = 356°F, which recipes round to 350°F.
2. 2°F to °C: subtract 32, multiply by 5, divide by 9. So 375°F → (375 − 32) × 5 ÷ 9 ≈ 190°C.
3. 3Gas marks: each step is 25°F, starting at Gas Mark 1 = 275°F. Gas Mark 4 is therefore 275 + (3 × 25) = 350°F.

While you're at it: the other recipe conversions

Temperature is one of three things that trip up cross-country recipes; the others are volume (cups vs millilitres) and weight (ounces vs grams). If your recipe mixes systems — American cups with a European oven, say — the cooking measurement converter handles cups, tablespoons, millilitres and grams so the ingredient amounts are as reliable as your newly-correct oven temperature.

The bottom line

Anchor on 180°C = 350°F = Gas Mark 4, subtract about 20°C for a fan oven, and use the multiply-by-9-divide-by-5-add-32 formula for anything between the rows. Get the oven right and the most common baking failure — browned outside, raw middle — largely disappears. Everything else is just following the recipe.