How to Convert Any Oven Recipe for an Air Fryer

You have a recipe open that says 400°F for 25 minutes, and an air fryer on the counter that you would rather use than heat the whole oven for one tray of chicken thighs. The recipe has no air fryer instructions, because most recipes do not.

The conversion is genuinely simple, and it is the same arithmetic every time. What is less obvious is which recipes convert at all — and that the two habits at the bottom of this page matter far more to the result than getting the temperature exactly right.

The conversion, in one line

Drop the temperature by 25°F (about 15°C) and cut the time by roughly 20%. Then start checking at two-thirds of the original time.

So that 400°F for 25 minutes becomes 375°F for about 20 minutes, with your first look at around 16 or 17 minutes. In Celsius, 200°C for 25 minutes becomes roughly 185°C for 20.

That last instruction is the one people skip and then regret. Air fryers vary enormously — a 4-litre basket model and an 8-litre dual-zone behave differently with the same numbers on the display — so the first time you convert a particular dish, treat the time as an estimate and your eyes as the authority.

Read the columns independently: any oven temperature pairs with any oven time. Most air fryers top out around 400–450°F, and many set in 5- or 10-degree steps, so round to the nearest setting your machine offers.

Why those numbers, and not some others

An air fryer is a small convection oven with an aggressive fan. Nothing is being fried. The fan moves hot air fast enough that heat transfers into the food considerably quicker than in a still oven, and the chamber is small enough to recover temperature almost instantly when you open it.

That is the whole explanation for both adjustments. The faster heat transfer is why the time comes down. The reason the temperature also comes down is that the surface would otherwise run ahead of the interior — you would get a dark crust over an underdone middle, which is the single most common air fryer disappointment.

It also explains why the conversion is more forgiving on thin things than thick ones. Chicken tenders, fries, sliced vegetables and fish fillets convert almost perfectly. A thick bone-in roast is where the crust-versus-centre problem bites, and where a thermometer stops being optional.

What it looks like on real dishes

Rounded to what an air fryer display can actually be set to:

Bone-in chicken pieces, thick pork chops and anything over about two inches thick: convert the temperature as above, ignore the time entirely, and cook to internal temperature.

Five recipes that do not convert

This is the part a conversion chart will not tell you, and it saves more dinners than the arithmetic does.

• Anything in a wet batter. Beer-battered fish, tempura, corn dogs. The fan blows liquid batter off the food and onto the element before it can set. Dry coatings — flour, egg, breadcrumbs, pressed on firmly — work beautifully. Wet ones do not.
• Anything soupy. Braises, casseroles with a lot of liquid, curries. There is nothing for the fan to do, and the liquid will simply sit there.
• Large roasts and whole birds. Not because it cannot be done, but because most baskets cannot hold one with air space around it, and air space is the entire mechanism.
• Loose light leaves. Kale chips are the classic disaster — untethered leaves fly into the heating element. If you insist, weigh them down or use a rack.
• Delicate risen bakes. Soufflés, chiffon cakes, anything whose structure depends on still air. The fan is not gentle.

The two habits that matter more than the numbers

Cook in a single layer, and accept batches. This is the difference between roasted and steamed, and it is where most conversions actually fail. Food piled two deep blocks the airflow that the whole appliance is built around; the pieces in the middle stew in their own moisture while the ones on top burn. Two batches in a single layer beat one crowded basket every time, and the second batch takes less time because the machine is already hot.

Shake or turn halfway. Air fryers have hot spots, usually toward the element. Thirty seconds of shaking is worth more than any temperature adjustment on this page.

Two smaller things: preheat for three to five minutes if the recipe involves anything crisping, and if you use parchment, make sure food is holding it down before the fan starts — loose parchment can lift into the element.

Use a thermometer, not the clock, for meat

Converted times are estimates by definition, so for anything where undercooking matters, temperature is the only honest test. The USDA safe minimums worth memorising: poultry 165°F (74°C), ground meat 160°F (71°C), pork and whole cuts of beef, veal and lamb 145°F (63°C) with a three-minute rest, and fish 145°F (63°C).

An instant-read thermometer costs less than one ruined chicken and removes the guessing permanently.

Where an app helps, and where it does not

Worth being straight about this: RecipeScan does not convert oven instructions into air fryer instructions for you. No app can reliably do that, because the answer depends on your machine, the thickness of what you are cooking and how full the basket is — the three things a recipe file knows nothing about.

What it does do is get the recipe onto your phone in the first place. Photograph a cookbook page, a handwritten card or a screen and the recipe becomes a proper ingredient-and-step list you can follow hands-free while cooking, with timers you start by voice instead of with greasy fingers. It also has plenty of recipes written for an air fryer from the start, which is generally better than converting one. And if you are cooking for a different number of people than the recipe assumes, it will scale the quantities for you — though remember that scaling the ingredients does not scale the basket, so a doubled recipe is two batches.

Do the conversion yourself with the line at the top of this page. Let the app handle getting the recipe there and keeping your hands free.

Frequently asked questions

Do I need to preheat an air fryer?

For anything you want crisp, yes — three to five minutes. For a slow bake it matters much less. Some models preheat so fast that the manual tells you not to bother; check yours.

Can I use foil or parchment in an air fryer?

Usually, with two conditions: never cover the whole base, because that blocks the airflow the machine works by, and never put either in empty before the food. Loose parchment can lift into the element.

Why is my food dry in the air fryer?

Almost always overcooking, because the converted time was treated as a rule rather than an estimate. Start checking at two-thirds. A light coat of oil on lean food helps; so does a rest before cutting.

Does the 25°F rule work in reverse?

Yes, roughly — add 25°F and about a quarter more time to take an air fryer recipe to a conventional oven. Expect it to be less crisp, because a full-size oven cannot move air the same way.

Do convection ovens need the same adjustment?

They need the temperature drop but not the same time cut. A convection setting on a full-size oven is usually about 25°F lower than the stated conventional temperature with only a slightly shorter time. The air fryer’s extra speed comes from its small chamber, not just from having a fan.