Convert oven times and temperatures for an air fryer

The standard adjustment is 20 °C down and 20 per cent off the time - But it only holds for some kinds of food, and knowing which is the difference between crisp chicken and a dry one.

Oven temperature Scale Oven time (minutes)

Air fryer at

For about

First check at

What an air fryer actually is, which explains the whole adjustment

An air fryer is a small fan oven with an aggressive fan and a basket that lets air reach the underside of the food. Nothing about it is frying. The name is marketing, and understanding that is the key to converting recipes into it, because everything it does well and badly follows from being a very efficient convection oven.

Because the chamber is small, it preheats in two or three minutes and recovers temperature almost instantly when you open it. Because the fan is strong and the food sits on a mesh, moisture is stripped from the surface quickly. That is why chips, wings and anything breaded work so well, and why a delicate sponge does not.

Where the twenty-and-twenty rule holds, and where it does not

The rule - Drop the temperature by 20 °C and cut the time by a fifth - Works reliably for food that is meant to end up dry and crisp on the outside: chips, roast potatoes, wings, breaded chicken, sausages, halloumi, frozen products of every kind.

It breaks down in three cases, and this is where most air fryer disappointment comes from:

Anything with a wet batter. It blows off the food and onto the element before it sets. Breadcrumbs and dry dredges are fine; a tempura or a beer batter is not.
Anything that needs to stay moist. A chicken breast with no coating comes out noticeably drier than it would in an oven, because the fan is doing exactly the job it is designed to do.
Anything that rises. Cakes, Yorkshire puddings and soufflés are at the mercy of a strong fan hitting an unset surface.

The one rule that matters more than the arithmetic

Check early. The “first check” figure above is roughly 55 per cent of the original time, and the reason it exists is that air fryers vary far more between models than ovens do. A 1,400 W basket model and a 1,800 W dual-drawer model at the same setting are not cooking at the same rate.

Shake or turn at that first check, look at the colour, and set a short timer from there. After two or three goes you will know your own machine, and this page becomes unnecessary - Which is the correct outcome for any converter.

How to convert an oven recipe for an air fryer

Enter the oven temperature and time Use the figures the original recipe gives for a conventional oven.
Read the air fryer settings Temperature drops by about 20 °C and time by about a fifth, and the page says which foods that rule does not hold for.
Check early A first-check time is given as well, because air fryers vary more between machines than ovens do.

Questions about moving a recipe into an air fryer

What is the rule for converting an oven recipe to an air fryer?

Drop the temperature by about 20 °C and cut the time by about a fifth, then check early. An air fryer is a small convection oven, so the adjustment is the same one you would make for a fan oven, with a shorter time because the cavity is small.

What does not work in an air fryer?

Anything with a wet batter, which blows off the food before it sets. Large quantities also fail, because an air fryer relies on air reaching every surface and a crowded basket steams instead of crisping.

Do I need to preheat an air fryer?

For anything cooked briefly, yes - two or three minutes. A cold start means the food sits in warm air while the machine catches up, which is the opposite of what an air fryer is for.