Reference
Gas Mark Conversion Chart
Every gas mark from ¼ to 9 in Fahrenheit, exact Celsius, the Celsius printed in UK recipes, and the fan oven equivalent.
Updated October 2026
| Gas Mark | °F | Exact °C | Recipe °C | Fan °C |
|---|---|---|---|---|
| Gas Mark ¼ | 225°F | 107.2°C | 110°C | 90°C |
| Gas Mark ½ | 250°F | 121.1°C | 120°C | 100°C |
| Gas Mark 1 | 275°F | 135°C | 140°C | 120°C |
| Gas Mark 2 | 300°F | 148.9°C | 150°C | 130°C |
| Gas Mark 3 | 325°F | 162.8°C | 160°C | 140°C |
| Gas Mark 4 | 350°F | 176.7°C | 180°C | 160°C |
| Gas Mark 5 | 375°F | 190.6°C | 190°C | 170°C |
| Gas Mark 6 | 400°F | 204.4°C | 200°C | 180°C |
| Gas Mark 7 | 425°F | 218.3°C | 220°C | 200°C |
| Gas Mark 8 | 450°F | 232.2°C | 230°C | 210°C |
| Gas Mark 9 | 475°F | 246.1°C | 240°C | 220°C |
How the gas mark scale works
Gas Mark is the temperature scale on gas cookers in the UK and Ireland, and you will still find it in British and Irish recipes and cookbooks. It is defined in Fahrenheit: Gas Mark 1 is 275°F and every mark after that adds 25°F, so Gas Mark 4 is 350°F and Gas Mark 9 is 475°F. Gas Mark ½ (250°F) and ¼ (225°F) are the very cool settings below Gas Mark 1.
Because the steps are 25°F, they are about 14°C apart, which doesn’t round neatly. That is why UK charts print rounded values such as 180°C for Gas Mark 4 (exactly 176.7°C), and why some charts disagree by 10°C for a mark or two. The “Recipe °C” column above matches the figures used by most UK recipe publishers.
Cooking by gas mark
- Gas ovens have zones. The top is hotter than the bottom, and the mark refers to the middle shelf.
- Preheat fully. Give the oven 15–20 minutes to reach the mark before baking.
- Converting to electric? Use the Recipe °C for a conventional electric oven, or the Fan °C for a fan oven.
- Converting from °C? If your temperature falls between two marks, use the nearer one and check early. The converter tells you when that happens.
Common questions
Why do some charts say Gas Mark 3 is 170°C?
Gas Mark 3 is 325°F, which is 163°C. Some charts round down to 160°C and some round up to 170°C. Either is fine for cooking.
Is there a Gas Mark 10?
A few older ovens go beyond Gas Mark 9, but the standard scale used in recipes runs from ¼ to 9.
Which shelf does the gas mark refer to?
The middle shelf. Gas ovens are hotter at the top and cooler at the bottom, which you can use to your advantage: roast potatoes up top, a slow-cooking dish lower down.
How do I use a gas mark recipe in an electric fan oven?
Look up the conventional °C for the gas mark, then subtract 20°C. Gas Mark 4 is 180°C, so use 160°C fan.