Oven Temperature Converter
Convert oven temperatures between Fahrenheit, Celsius, and gas mark.
Input sheet
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Recipes from the UK and Europe list oven temperatures in Celsius or gas marks, while US recipes use Fahrenheit. This converter translates between all three so a recipe written for one oven works in yours.
How it works
C = (F − 32) × 5/9; gas mark steps ~14 C each from gas mark 1 at ~135 C.
Fahrenheit to Celsius is the standard conversion: subtract 32, then multiply by five-ninths. Gas marks are a British scale where each step is roughly 14°C, anchored near gas mark 1 at about 135°C, climbing to gas mark 9 at the high end.
The descriptive bands help when a recipe just says 'hot oven': below about 300°F is a slow oven, 300–375°F is moderate, 375–425°F is hot, and above that is very hot. These are useful sanity checks when a translated number looks off.
Celsius = (Fahrenheit − 32) × 5/9; gas mark ≈ (Celsius − 135) ÷ 14 + 1
Worked examples
A US recipe calls for a 350°F oven; you have a Celsius dial. → 177°C, gas mark 4 (a moderate oven)
(350 − 32) × 5/9 = 176.7 ≈ 177°C; (176.7 − 135) ÷ 14 + 1 ≈ gas mark 4.
Converting a 425°F roasting temperature. → 218°C (a hot oven)
(425 − 32) × 5/9 = 218.3 ≈ 218°C.
Tips & gotchas
- Drop the dial about 25°F (roughly 15°C) for a fan-assisted or convection oven — fan ovens cook faster than the conventional temperatures most recipes assume.
- Home ovens routinely run 25°F off their setpoint. A standalone oven thermometer (around $10) tells you what your oven actually does versus what the dial claims.
- Gas marks outside 1–9 fall off the usable scale — very low or very high targets just don't map to a standard gas-mark number.
- For delicate bakes like custards or meringues, exact temperature matters more than for roasting, where there is more forgiveness.
FAQ
Should I adjust the temperature for a fan oven?
Yes. A convection or fan oven moves hot air across the food, so it cooks faster. Reduce the conventional Celsius temperature by about 15–20°C (or 25°F) unless the recipe was already written for a fan oven.
What is a gas mark?
It is the British oven dial scale, numbered roughly 1 to 9 instead of degrees. Each mark is about 14°C apart, starting near 135°C at gas mark 1. Gas mark 4 (about 180°C / 350°F) is the everyday baking setting.
Why does my oven not match the set temperature?
Thermostats drift and ovens have hot and cool spots. It is common to be off by 25°F or more. Verify with an oven thermometer and rotate pans partway through bakes to even out the difference.
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