Gas Mark 4, Fan Ovens and Dessertspoons: How to Follow a British Recipe in North America

You’ve found the perfect recipe for a Victoria sponge or a sticky toffee pudding, and it asks you to bake at “Gas Mark 4, or 160°C fan”. If you grew up with Fahrenheit and measuring cups, half of that sentence is a puzzle. Here’s what British and Australian recipes mean, and how to convert them.

Gas Mark

Gas Mark is the temperature scale printed on British gas ovens. Each step is roughly 25°F, and it’s easy to convert once you know a few landmarks.

Gas Mark	°C	°F
1	140	275
2	150	300
3	170	325
4	180	350
5	190	375
6	200	400
7	220	425
8	230	450

The one to remember is Gas Mark 4 = 180°C = 350°F: the everyday cake temperature on both sides of the Atlantic.

Fan ovens

A fan oven (a convection oven in North America) blows hot air around the food, so it cooks faster and more evenly. Recipes compensate by setting the fan temperature about 20°C lower than a conventional oven. When a British recipe says “180°C, 160°C fan”, those are the same bake on two kinds of oven.

The mix-up happens when a recipe gives only one number. Many UK and Australian recipes assume a fan oven by default, so if you bake one at that temperature in a conventional oven, it can come out underdone. Check whether the recipe says “fan”, and if your oven has no fan, add about 20°C.

Spoons and cups aren’t the same size everywhere

Spoons look universal, but they aren’t:

• A teaspoon is 5 mL nearly everywhere.
• A dessertspoon, common in British recipes, is 10 mL: two teaspoons.
• A tablespoon is 15 mL in the UK and close to that in the US, but 20 mL in Australia. An Australian recipe calling for a tablespoon of baking powder means a third more than an American tablespoon.
• A cup is about 237 mL in the US but 250 mL in Australian and Canadian metric recipes.
• A pint is 568 mL in the UK and only 473 mL in the US. A British pint of milk is about 20 percent more than an American one.

Grams, not cups

Most British recipes measure dry ingredients by weight: 225 g of flour, 175 g of sugar. You can convert these to cups, but you’ll lose accuracy, because a cup of flour can weigh anywhere from 120 g to 150 g depending on how you fill it. (We wrote about why cups and grams don’t convert simply.) A kitchen scale is the easiest way to follow British baking recipes exactly as written.

Pan sizes

British tins are usually given in centimetres: a 20 cm round is close to an 8-inch pan, and a 23 cm round is close to a 9-inch one. Close isn’t always good enough. A 9-inch round has about 26 percent more area than an 8-inch, so the same batter bakes thinner and faster.

Doing all of this in one place

KitchenCalc was built for exactly this kind of recipe. It converts between Celsius, Fahrenheit, Gas Mark, and fan Celsius and Fahrenheit in any direction. It knows the British dessertspoon and uses the modern metric spoon sizes UK recipes mean. It converts grams to cups using each ingredient’s real density rather than a single number for everything.

For pans, it compares the area of the tin the recipe wants with the one you own. Swap a metal 8-inch round for a glass 9-inch round, and it tells you the area is 26 percent larger, to scale the batter by 1.27×, and to drop the oven by 25°F because glass holds heat differently.

It’s a one-time purchase for the Mac, with no account and no internet connection needed for any of the conversions.