Guide · Published October 26, 2026 · By the site maintainer
Oven temperatures in Celsius, Fahrenheit, and Gas Mark
The setting most home cooks need is Gas Mark 4 = 350 °F = 180 °C. Every other working oven temperature is in the chart below. Oven settings are conventional round numbers, not exact conversions — 180 °C is exactly 356 °F, but no recipe means that, and every publisher rounds it to 350 °F.
Three systems survive in cookbooks because of where and when they were written. US recipes use Fahrenheit. Most of the world uses Celsius. British recipes written for gas ovens use Gas Mark, a scale introduced with early twentieth-century gas cookers, where each mark is a step of heat rather than a temperature you can derive from the others by formula alone.
The complete oven temperature chart
| Gas Mark | Fahrenheit | Celsius | Description |
|---|---|---|---|
| ¼ | 225 °F | 110 °C | Very slow — meringues, slow drying |
| ½ | 250 °F | 130 °C | Very slow — rich fruit cakes |
| 1 | 275 °F | 140 °C | Slow — braises, low roasting |
| 2 | 300 °F | 150 °C | Slow — custards, cheesecakes |
| 3 | 325 °F | 170 °C | Moderately slow — fruit cakes, flans |
| 4 | 350 °F | 180 °C | Moderate — cakes, cookies, casseroles |
| 5 | 375 °F | 190 °C | Moderately hot — breads, pies |
| 6 | 400 °F | 200 °C | Hot — roasting vegetables, pastry |
| 7 | 425 °F | 220 °C | Hot — pizza, flatbreads |
| 8 | 450 °F | 230 °C | Very hot — searing, artisan bread |
| 9 | 475 °F | 240 °C | Very hot — maximum for most home ovens |
Notice the pattern: each Gas Mark step is 25 °F, and the Celsius column is the rounded value cooks actually set, not the exact mathematical conversion. That is deliberate. Oven thermostats cycle above and below the set point by more than the rounding in this table, so chasing an exact 176.7 °C for a 350 °F recipe would be false precision. Our rounding guide explains where that line sits for other measurements.
The fan-assisted (convection) adjustment
A fan oven circulates hot air, so food cooks as if the temperature were higher. The standard adjustment is to set the temperature 20 °C lower than the conventional Celsius figure — roughly 25 to 30 °F lower than the Fahrenheit figure. A recipe at 180 °C conventional becomes 160 °C in a fan oven. Many modern ovens print both scales or convert automatically; when a recipe says "180 °C / 160 °C fan / Gas 4," the middle number has already done this adjustment for you.
Reduce the temperature rather than the time as your first change. Shortening the time as well is the most common way fan-oven conversions go wrong, especially for cakes, which need the full time for structure to set even at a lower temperature.
Converting a temperature that is not on the chart
For anything between the standard settings, use the exact formulas and then round to the nearest settable number:
- Celsius to Fahrenheit: multiply by 9/5 and add 32. Example: 165 °C × 9/5 + 32 = 329 °F, set 325 °F.
- Fahrenheit to Celsius: subtract 32 and multiply by 5/9. Example: (425 − 32) × 5/9 = 218.3 °C, set 220 °C.
- Gas Mark: above Mark 1, each mark is about 13 to 14 °C (25 °F). Mark 4 is 180 °C; count up or down from there.
The Celsius and Fahrenheit converter handles the exact arithmetic for any value, and the temperature scales guide explains why the formula needs the offset of 32 at all.
When a few degrees actually matter
Most roasting and casseroles forgive 10 °C in either direction. Three situations do not forgive much:
- Sugar work and candy: Stages like soft ball and hard crack are defined within a few degrees. Convert exactly, and use a thermometer rather than the dial.
- Meringues and drying: At Gas ¼ to ½, a small overshoot colors and then burns. Err low and extend the time.
- Food safety: Internal temperatures for poultry and reheated dishes are minimums, not targets. Convert with the exact formula and verify with a probe; our recipe conversion guide lists the common internal temperatures in both scales.
Finally, trust an inexpensive oven thermometer over any dial. Home ovens routinely run 10 to 15 °C away from their setting, an error larger than every rounding in the chart above. Converting carefully and then verifying the actual temperature is the whole job.