Three systems, one reason they exist
Fahrenheit is standard in US recipes, Celsius is standard almost everywhere else, and gas mark is a older UK/Australian numbering system from the era of gas ovens without precise dial temperatures — it groups temperatures into numbered bands rather than exact degrees, which is why converting a specific Fahrenheit or Celsius value to gas mark gives you the nearest standard mark rather than a precise one-to-one number. If a recipe's origin isn't stated, US recipes are almost always Fahrenheit, UK/Australian recipes commonly still reference gas mark alongside Celsius, and most other countries use Celsius exclusively.
Common oven temperature reference points
A few benchmarks worth memorizing: 350°F/177°C (gas mark 4) is the most common "moderate" baking temperature, used for cakes and most everyday baking. 325°F/163°C (gas mark 3) is a common "low and slow" temperature for delicate bakes or larger cuts of meat. 425°F/218°C (gas mark 7) is a common "hot oven" setting for roasting vegetables or getting a good crust. These aren't exact rules, but they're useful anchors when a recipe just says "moderate oven" without a specific number.
Quick reference chart
| Fahrenheit | Celsius | Gas Mark | Description |
|---|---|---|---|
| 275°F | 135°C | 1 | Very low |
| 300°F | 149°C | 2 | Low |
| 325°F | 163°C | 3 | Low-moderate |
| 350°F | 177°C | 4 | Moderate |
| 375°F | 190°C | 5 | Moderately hot |
| 400°F | 204°C | 6 | Hot |
| 425°F | 218°C | 7 | Hot |
FAQ
Why doesn't my exact Celsius value match a whole gas mark number? Gas mark is a stepped scale representing ranges, not exact degrees — the converter shows the nearest standard mark for your temperature.
Is this the same as a convection/fan oven temperature? No — these are the standard (non-fan) oven temperatures. See our convection oven converter for the separate fan-oven adjustment.