Oven temperature converter
Enter an oven temperature, get it in °F, °C and gas mark.
What is 350 °F in Celsius?
176.7 °C exactly — recipes round it to 180 °C, which is gas mark 4.
How do I convert oven temperatures?
°C = (°F − 32) × 5 ÷ 9, and °F = °C × 9 ÷ 5 + 32. 425 °F is 218.3 °C, written as 220 °C in recipes.
What is a gas mark?
The temperature scale on British gas ovens. There is no official standard for it — the usual table starts at gas mark 1 = 275 °F (140 °C) and adds 25 °F for each mark, so gas mark 4 is 350 °F and gas mark 6 is 400 °F.
Why do recipes round the Celsius temperature?
Oven dials go in steps of 10 °C, and ovens are rarely accurate to a few degrees anyway. 176.7 °C becomes 180 °C, 162.8 °C becomes 160 or 165 °C.
What about fan or convection ovens?
Fan ovens cook faster at the same setting, so recipes often give a lower temperature for them. How much lower depends on the oven — check its manual.
What is 375 °F in Celsius and gas mark?
190.6 °C exactly. Recipes write 190 °C, which is gas mark 5.
How do I convert 160 °C to Fahrenheit?
160 × 9 ÷ 5 + 32 = 320 °F. The nearest gas mark is 3 (325 °F), so a recipe will usually list 325 °F.
How the conversion works
Water freezes at 32 °F and 0 °C and boils at 212 °F and 100 °C, so 180 Fahrenheit degrees span the same range as 100 Celsius degrees. That is the ratio 9 to 5. To go from Fahrenheit, subtract the 32-degree offset first and then multiply by 5 ÷ 9; to go from Celsius, multiply by 9 ÷ 5 first and then add 32. Mixing the order of the two steps is the usual source of errors.
Worked examples
425 °F: (425 − 32) × 5 ÷ 9 = 218.3 °C, shown in recipes as 220 °C or gas mark 7. 200 °C: 200 × 9 ÷ 5 + 32 = 392 °F, which sits on gas mark 6. Notice that recipe conversions are rounded to the nearest convenient dial setting, so a converted figure and a recipe’s printed figure can differ by a few degrees without either being wrong.
Gas marks
The gas mark table used here runs from mark ¼ (225 °F, 110 °C) to mark 10 (500 °F, 260 °C). From mark ¼ upward each step is 25 °F, which is why the Celsius equivalents move in uneven 10 or 20 degree jumps once rounded. Gas marks come from British cookery, so if you are using an American recipe on a gas-mark oven, convert to Celsius first and then pick the nearest mark.
Common mistakes
Reading a fan (convection) oven recipe as a conventional one is the most common one: the figure printed may already be lowered for the fan, so check which kind of oven the recipe is written for. Setting the dial and trusting it is another; home ovens can run well off their dial, and an inexpensive oven thermometer shows the real temperature. Finally, do not apply this converter to cooking times, which do not scale with the temperature conversion.
Sources: the Celsius–Fahrenheit relation is the NIST definition of the two scales (the ice and steam points of water); the gas mark table follows the commonly published chart, which has no official standard. Related: cooking measurement converter, cake pan converter and recipe scaler.