Gas Mark to Celsius Converter

Gas mark is the temperature scale used on gas ovens in the UK, Ireland, and some Commonwealth countries. Gas marks run from 1 (very cool, 140°C) to 9 (very hot, 240°C). Older British recipe books use gas marks exclusively, and many classic recipes still reference them without providing Celsius equivalents.

The relationship between gas marks and Celsius is not linear — each gas mark is roughly 10–14°C higher than the previous one. Gas Mark 4 (180°C) is the central reference point, used in the majority of everyday baking recipes. Gas Mark 6 (200°C) is the standard roasting temperature for most meats and vegetables.

Modern electric ovens do not have gas marks, so this converter is essential for following older recipes. If you have a fan-assisted electric oven, take the Celsius equivalent and subtract 20°C to find your fan oven setting. Gas Mark 4 (180°C) in a conventional gas oven becomes 160°C in a fan-assisted electric oven.

Gas ovens can have hot spots and temperature variation. The top of a gas oven is typically hotter than the bottom. For even baking, place dishes on the middle shelf and consider rotating them halfway through cooking, particularly for cakes and pastries where even browning is important.