Toolman

Gas mark 1/2

130°C · 250°F · 110°C fan

Very cool oven — very slow braises, overnight cooking.

Gas mark 1/2 in every scale

Gas mark1/2
Fahrenheit250°F (exact — gas mark 1/2 is defined as this)
Celsius, conventional oven130°C (the arithmetic conversion is 121.1°C; recipes round it)
Celsius, fan oven110°C
Fahrenheit, fan oven230°F
DescriptionVery cool

Frequently asked questions

What is gas mark 1/2 in Celsius?

130°C in a conventional oven, or 110°C in a fan oven.

What is gas mark 1/2 in Fahrenheit?

250°F, exactly — gas mark 1/2 is defined as 250°F.

Why is gas mark 1/2 called 130°C when 250°F is 121.1°C?

Because 121.1°C is not a number an oven dial can be set to. Recipes round to the nearest ten, and the rounded figure is the convention everywhere — the 8.9 degree difference is well inside the accuracy of a domestic thermostat.

What is gas mark 1/2 used for?

Very cool — very slow braises, overnight cooking.

The settings either side

Gas markFahrenheitCelsiusFan / convection
1/4225°F110°C90°C fanVery cool
1/2250°F130°C110°C fanVery cool
1275°F140°C120°C fanCool

The full chart, and why the three scales disagree →

All oven temperatures · 130°C to °F precisely · Cooking measurements