Fan oven conversion chart
Conventional | Fan oven | Fahrenheit | Gas mark |
|---|---|---|---|
140°C | 120°C | 275°F | 1 |
150°C | 130°C | 300°F | 2 |
160°C | 140°C | 325°F | 3 |
180°C | 160°C | 350°F | 4 |
190°C | 170°C | 375°F | 5 |
200°C | 180°C | 400°F | 6 |
220°C | 200°C | 425°F | 7 |
230°C | 210°C | 450°F | 8 |
240°C | 220°C | 475°F | 9 |
Why a fan oven needs a lower setting
In a conventional oven the air is still, and a layer of cooler air sits around the food. A fan keeps the air moving, which carries heat to the surface faster and evens out hot and cool spots. The same dish browns sooner, so the setting comes down to compensate.
Which oven does the recipe mean?
A recipe from the United Kingdom, Ireland or Australia often gives both, written as 200°C/180°C fan. If it gives one number and says nothing, it usually means a conventional oven.
A recipe from the United States assumes a conventional oven unless it says convection.
A recipe that gives a gas mark means a conventional oven. Gas ovens have no fan setting.
If your oven only has a fan, subtract 20°C from a conventional recipe. If it only has conventional heat, add 20°C to a fan recipe.
When the fan matters, and when it does not
The fan helps most when you want browning and when the oven is full: roast vegetables, roast chicken, two trays of cookies at once. Many bakers turn it off, if the oven allows, for things that should rise gently and stay pale, such as custards and delicate cakes.
Quick answers
Is 180°C fan the same as 200°C? Yes. 180°C fan is 200°C in a conventional oven, 400°F or gas mark 6.
What is 350°F in a fan oven? 160°C fan. In a conventional oven 350°F is 180°C, gas mark 4.
What is gas mark 4 in a fan oven? 160°C fan.
What is 160°C fan in Fahrenheit? 350°F.
For any other temperature, use the oven temperature converter: choose Celsius (fan) on one side and the scale you need on the other.
Sources and method
The chart and the rule of about 20°C follow the oven temperature conversion table published by Which?, the UK consumer organization. The 25°F rule for convection ovens is the convention in American recipes. Ovens vary, so the first time you convert a recipe, check it a few minutes early.
