Convert oven temperatures for international recipes, with an optional fan/convection adjustment.
| Fahrenheit | Celsius | Gas Mark | Description |
|---|
Enter a temperature in Fahrenheit or Celsius and read the other, plus the gas mark and the word a British recipe would use for that heat. The reference table below the result shows where your number sits on the whole scale, which is more useful than a single conversion when a recipe says "gas mark 6" and your oven only has numbers.
Tick the fan box if you are cooking in a convection oven. It subtracts 25°F or 20°C from the conventional figure, which is the usual adjustment rather than a law of physics.
A cake recipe written for a British kitchen says 180°C, fan 160°C.
| Reading | Value |
|---|---|
| Conventional | 180°C = 356°F, gas mark 4 |
| With the fan box ticked | 331°F / 160°C |
| The other direction | 350°F = 177°C, gas mark 4 |
Note the asymmetry: 180°C converts to 356°F, which most ovens would round to 350°F, and 350°F converts back to 177°C rather than 180°C. That two-degree gap is why a recipe written in one system and followed in the other sometimes needs an extra few minutes. It is rounding, not a different cake.
The conversion is exact arithmetic: Fahrenheit to Celsius is minus 32, times five, divided by nine. The gas mark is not arithmetic at all. It is a numbered scale that grew out of the notches on British gas ovens, and each number is roughly 25°F apart, which is why gas mark 4 is 350°F and gas mark 6 is 400°F. The table on this page is the conventional mapping; individual ovens vary by more than the gap between two marks.
That is the honest caveat about any oven conversion. A domestic oven set to 350°F cycles somewhere around that temperature, often swinging 20°F either way, and an oven thermometer usually shows the truth. Use the conversion to get the dial right, then trust the cake: if it is browning faster than the recipe predicts, the oven is running hot regardless of what the display says.
Convection moves heat differently rather than simply running hotter, so the 25°F reduction is a starting point. Dense bakes and anything in a deep tin often need the full reduction plus a shorter time; thin cookies may need less.
350°F, or 180°C. It is the most common baking temperature in British recipes and the default on this page.
Usually, by about 20°C. Check the manual for your oven, since some manufacturers build the adjustment in and expect you to set the conventional number.
Because it was written for both convection and conventional ovens. The lower number is the fan setting, and using the higher one in a fan oven will overbake the outside.
The degrees are, but oven dials are not. A European oven marked 180 means 180°C conventional; some US ovens labelled in Celsius are converted from Fahrenheit and land on odd numbers.
Not meaningfully. Slow cookers are described as low, high, and warm, with no standard temperature, so there is nothing to convert.
The temperature formulas are exact. Gas marks are a British dial convention, not an SI unit.
Last updated: November 2, 2026. Reviewed by David Liu.