Oven temperatures translated for your kitchen
Convert Fahrenheit, Celsius, and approximate Gas Mark settings before the oven preheats.
Oven temperatures appear in different languages depending on the cookbook, appliance, and country. US recipes usually use Fahrenheit, many international recipes use Celsius, and older British recipes may use Gas Mark. KitchenCalc translates between those systems and puts the approximate setting in one result so you can move on to the recipe with less uncertainty.
Fahrenheit and Celsius have a straightforward mathematical relationship: subtract 32 from Fahrenheit, then multiply by 5/9. To go the other way, multiply Celsius by 9/5 and add 32. Gas Mark is different. It is a practical sequence of approximate oven settings rather than a perfectly even mathematical scale. The tool uses the familiar GM1 through GM9 reference and chooses the closest setting for temperatures between those marks.
Gas Mark 1 is about 275°F or 140°C; GM2 is 300°F/150°C; GM3 is 325°F/160°C; GM4 is 350°F/180°C; GM5 is 375°F/190°C; GM6 is 400°F/200°C; GM7 is 425°F/220°C; GM8 is 450°F/230°C; and GM9 is 475°F/240°C. Treat those values as useful guidance, not laboratory calibration. Oven thermostats vary, and the center of the oven can be warmer or cooler than the dial suggests.
Fan or convection ovens move hot air more actively, so many recipes start about 25°F, or roughly 15°C, lower than a conventional setting. Use that as a practical starting point and check your food early. Pan color, material, rack position, and batter depth also affect timing. A converted temperature is a good translation, while the first batch teaches you how your own oven behaves.
Reference table
| Gas Mark | Fahrenheit | Celsius |
|---|---|---|
| 1 | 275°F | 140°C |
| 3 | 325°F | 160°C |
| 4 | 350°F | 180°C |
| 6 | 400°F | 200°C |
| 9 | 475°F | 240°C |
Worked example
Example: 200°C is 392°F, closest to Gas Mark 6. In a fan oven, begin around 365–370°F and check early.
Frequently asked questions
Are Gas Mark values exact?
No. They are approximate reference points that vary with the oven and the source recipe.
How much should I reduce for convection?
A common starting point is 25°F or about 15°C, followed by an early doneness check.