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Conversionscooking

Oven Temperature Converter

Oven temperatures across Celsius, Fahrenheit and gas mark, with the fan oven adjustment. A fan oven runs about twenty degrees Celsius hotter in effect, so recipes written for conventional ovens need reducing.

Also called: gas mark converter, celsius to fahrenheit oven.

From
Celsius
180

180°C, 356°F, gas mark 4.24. For a fan oven, set about twenty degrees Celsius lower than a conventional recipe states. moderate, the usual baking range

Fahrenheit
356
Gas mark
4.24
Fan oven equivalent in Celsius
160
Typical use
moderate, the usual baking range
On fan ovens
For a fan oven, set about twenty degrees Celsius lower than a conventional recipe states.
How this is calculated
Method and background

How this is calculated

Celsius and Fahrenheit differ in both degree size and zero point, so the conversion needs both a factor and an offset. Gas marks are a British scale where mark 1 is 275°F and each mark adds 25°F. The fan adjustment is the practical part: circulating air transfers heat faster, so a fan oven at the same setting cooks as though it were about twenty degrees Celsius hotter, and a recipe written for a conventional oven should be set twenty lower.

the two scales have different zero points as well as different degree sizes, which is why the conversion has an offset
C, F
The two scales

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

a standard baking temperature

Temperature
180
From
Celsius
Fan or convection oven
No

Celsius180

180 x 9/5 + 32

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gas mark 4 converts back

Temperature
4
From
Gas mark
Fan or convection oven
No

Celsius176.7

boundary: mark 1 is 275F plus 3 x 25

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the scales cross at minus forty

Temperature
-40
From
Celsius
Fan or convection oven
No

Celsius-40

degenerate case: the one temperature where the scales agree

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Method and limits

What it assumes

  • A twenty degree Celsius fan reduction, which is the common convention.

What it deliberately does not model

  • Ovens vary from their dial by more than the fan adjustment. An oven thermometer settles it.
  • Some manufacturers recommend a 25 degree reduction rather than 20.

Formula version 1.0.0 · definition 1.0.0 · United States · Report a problem with this calculator

Frequently asked questions

Do I reduce the temperature for a fan oven?
Yes, by about twenty degrees Celsius from what a conventional recipe states. Circulating air transfers heat faster at the same dial setting.
What is gas mark 4?
180°C or 350°F, the most common baking temperature. Each gas mark is 25°F, starting from mark 1 at 275°F.