The full oven conversion chart
The one rule to remember: fan (convection) ovens cook about 25°F (15–20°C) hotter than the dial says, because moving air transfers heat faster. So for a conventional-oven recipe, set a fan oven roughly 25°F / 20°C lower.
| Description | Fahrenheit | Celsius | Gas mark | Fan oven (°C) |
|---|---|---|---|---|
| Very cool (warming) | 225°F | 110°C | 1/4 | 90°C |
| Cool | 250°F | 120°C | 1/2 | 100°C |
| Very low (slow roast) | 275°F | 140°C | 1 | 120°C |
| Low | 300°F | 150°C | 2 | 130°C |
| Moderately low | 325°F | 160°C | 3 | 140°C |
| Moderate (most baking) | 350°F | 180°C | 4 | 160°C |
| Moderately hot | 375°F | 190°C | 5 | 170°C |
| Hot | 400°F | 200°C | 6 | 180°C |
| Very hot | 425°F | 220°C | 7 | 200°C |
| Very hot (roasting) | 450°F | 230°C | 8 | 210°C |
| Extremely hot | 475°F | 240°C | 9 | 220°C |
| Pizza / max | 500°F+ | 260°C+ | - | 240°C+ |
What the common settings are for
Three numbers cover most cooking
- 350°F (180°C, gas 4) - the default for cakes, cookies and casseroles. Gentle enough to cook through without burning the outside.
- 400°F (200°C, gas 6) - roast vegetables, chicken pieces and anything you want browned and crisp.
- 450°F (230°C, gas 8) - pizza, bread with a burst of oven spring, and hard sears.
Convert any exact value with the Fahrenheit to Celsius converter, and once the food is in, judge doneness with a thermometer, not the clock.
Why ovens lie to you
Home ovens routinely run 25–50°F away from their dial setting and swing further as the thermostat cycles. A $10 oven thermometer placed on the middle rack tells the truth. Preheating matters too: most ovens need 15–20 minutes to truly stabilize, not the 5 minutes the beep suggests. If bakes consistently brown too fast at the top, the oven likely runs hot - drop the dial 15°F and note the result.
Bake, roast, broil: what the modes actually do
- Bake heats mostly from the bottom element with gentle ambient heat - the default for anything with batter or dough.
- Roast (on ovens that separate it) runs hotter top heat for browning meat and vegetables.
- Broil is direct top-element heat at roughly 500-550°F (260-290°C) - effectively an upside-down grill. Food sits inches from the element and turns in minutes, so stay nearby.
- Fan / convection circulates air for even color and faster cooking - and is exactly why fan recipes need the 25°F reduction covered above.
When to use convection (and when not to)
The fan is your friend for roasted vegetables, whole birds, cookies on multiple trays, and anything that should brown and crisp - moving air sweeps away the moist boundary layer and delivers heat faster.
Switch it off for delicate batters: soufflés, custards, flans, and many cakes rise lopsided or skin over when air blasts them. When in doubt, follow the recipe’s mode, apply the fan conversion from the chart, and confirm doneness with an internal thermometer - the meat temperature chart is the final word for anything with muscle in it.
Conversion fixes the scale, not the oven
A correct Celsius-to-Fahrenheit conversion cannot account for an oven that runs hot, cycles widely or places its sensor far from the food. Fan-assisted ovens can also cook differently from conventional ovens even when the displayed number is converted perfectly. Treat a recipe conversion as the starting setting, then use the recipe’s visual and internal-temperature cues.
For repeatable baking, place an oven thermometer near the working shelf and observe several heating cycles. Do not recalibrate from one instant, because thermostats normally switch heat on and off around a target. If the average remains consistently different, follow the appliance instructions or arrange service rather than applying a different mental correction to every recipe.
Keep temperature and cooking mode together in your notes: for example, conventional or fan, shelf position, pan type and actual result. That record is more useful than assuming every oven marked 180°C produces the same heat around the food.