Gas Mark 3 in Celsius
Gas mark 3 is 160 °C.
Try your own numbers
Last checked 11/11/2026. Sources: Which?: Oven temperature conversion table (gas marks 1 to 9 with fan temperatures; fan ovens about 20 °C lower); Wikipedia: Gas mark (gas marks ¼ and ½; marks rise 25 °F each; prints 170 °C for gas mark 3).
Gas Mark 3 in Celsius: the working
Charts disagree about gas mark 3. Which? gives 160 °C and some cookery sites give 170 °C. This page uses 160 °C, and a thermometer settles it for your oven.
Gas mark 3 is 160 °C (325 °F) on the usual chart. 160 °C × 9 ÷ 5 + 32 = 320 °F. The dial value is rounded to the nearest 10 °C or 25 °F.
Common questions
What is the exact conversion?
160 °C is 320 °F. The dial value is rounded to 160 °C or 325 °F.
Do I need to change it for a fan oven?
A recipe written for a conventional oven is usually set about 20 °C (25 °F) lower in a fan oven. Many ovens do this for you, so check your manual and your oven thermometer.