How to Convert Oven Recipes to the Air Fryer (Time and Temp Rule)

You have a recipe you love and an air fryer on the counter, and the recipe was written for an oven. You do not need a new cookbook. You need one small piece of arithmetic and a few notes on where it stops working.

The conversion rule is not precise, and nobody serious pretends it is. It gets you to a sensible starting point. A thermometer and a look at the food settle everything after that. Treat it as a first guess rather than a promise and you will convert almost anything without ruining dinner.

The rule in one line

Drop the oven temperature by 25F, cut the cooking time by about 20 percent, and start checking at the halfway mark.

That is the whole thing. A recipe calling for 400F for 30 minutes becomes 375F for about 24 minutes in the air fryer, with your first look at around the 12 minute mark. Food Network gives the same 25F reduction, and the 25F plus 20 percent pairing is the standard advice across recipe sites and conversion charts.

For Celsius recipes, knock off about 15C and take the same 20 percent off the clock. If your recipe was already written for a fan or convection oven, it has had the reduction applied once already, so keep the stated temperature and simply trim the time.

Why the rule works

An air fryer is a small convection oven with an aggressive fan. Two things follow from that.

The moving air strips away the cool, humid layer that sits against food in a still oven, so heat transfers faster at the same dial setting. That is the 25F. And the cooking chamber is tiny, so it comes up to temperature quickly and the walls sit close to the food, which reflects heat back at it. That is the 20 percent.

It also explains why the rule holds up better for some foods than others. Anything that wants dry, direct heat and a browned surface converts beautifully. Anything that depends on a gentle, still environment to set or rise is where you start making adjustments. If you want the longer version of how the airflow shapes your results, our guide to choosing an air fryer covers what the fan and the basket shape actually do.

The four step method

1. Write down the oven numbers. Temperature and total time, straight from the recipe. 2. Subtract 25F and multiply the time by 0.8. Thirty minutes becomes 24. Forty five becomes 36. Twenty becomes 16. 3. Preheat, then load a single layer. Most conversions fail on crowding, not on math. Food needs space around it or you are steaming, not air frying. 4. Check at halfway, then every few minutes. Shake or flip at that first check. Pull the food when it is done, not when the timer says so.

Step three deserves a word of warning, because it is the one people skip. An oven recipe is usually written for a full sheet pan. Your basket is a fraction of that. Halve or quarter the batch and cook in rounds rather than piling it in. We wrote up the whole list of habits that sabotage new owners in common air fryer mistakes beginners make, and crowding sits at the top for a reason.

The conversion chart

Common oven settings, converted. Round to whatever your air fryer's dial or buttons actually allow.

That last row is the common snag. Plenty of basket air fryers top out around 400F, so a 450F oven recipe cannot be matched exactly. Run it at your maximum, keep the 20 percent time cut as your starting estimate, and expect to add a couple of minutes at the end. Browning will be a little gentler than the recipe intends, which matters for a blistered pizza and matters not at all for a tray of vegetables.

Sanity check your answer against known air fryer times

Arithmetic is a starting point, not a verdict. Before you commit, it is worth comparing your converted number against published air fryer times for the same food. Taste of Home's air fryer time chart is a useful cross reference:

If your converted number lands miles away from the published one, the conversion is probably not the problem. Check your portion size and thickness first, because a thin cutlet and a thick one cook nothing alike no matter what the dial says.

Where the rule needs a tweak

Baking

Anything with a soft crumb is the rule's weakest spot. The fan hits the top of the batter hard, so the surface sets and browns before the middle has any idea what is happening. Cut a little deeper on temperature, closer to 30F below the oven figure, give it back some of the time you took off, and tent the top loosely with foil if it colors too fast.

Pan size is the real constraint. A standard 9 by 13 dish will not go anywhere near most baskets. You are working with six or seven inch rounds, small loaf pans, ramekins, and silicone molds, which usually means scaling a standard recipe down to a third or a quarter. That is fine for brownies. It is a nuisance for a layer cake, and an oven is simply the better tool there.

Frozen food

Check the bag first. Most frozen fries and nuggets now print air fryer directions right next to the oven ones, and the manufacturer's numbers beat any conversion you can calculate. Use the rule only when the bag is silent.

Large roasts and whole birds

A whole chicken or a big roast can cook unevenly in a basket, because the part nearest the element browns long before the center is safe. Lower the temperature further than the rule suggests, plan on turning it partway through, and let an instant read thermometer make the call. Small cuts and portions convert far more reliably than anything you have to carve.

Wet batter and saucy dishes

Thin, wet batter is a hard no. Tempura and beer batter drip straight off before they can set, leaving a puddle in the drawer and a bare piece of food above it. Breaded and crumbed coatings, on the other hand, are exactly what the machine is built for. Heavily marinated food browns poorly too, so pat it dry before it goes in. Casseroles and anything soupy can work in a suitable dish, but you lose the crisping advantage, which is most of the reason you reached for the air fryer.

Light, loose ingredients

Kale chips and anything light enough to fly will get picked up by the fan and thrown at the heating element, where it scorches and smokes. Weigh it down with a rack, or cook it in the oven. The same logic applies to loose parchment, which is worth reading up on in our piece on using parchment paper in an air fryer safely.

Cook to temperature, not to the timer

Every conversion is an estimate. Doneness is not. For anything with a food safety floor, the thermometer outranks the clock, and the USDA's safe minimum internal temperatures are the numbers that matter:

Measure before you pull the food out, and check the thickest part away from bone. This single habit turns a rough conversion into a reliable one, because you stop needing the time estimate to be right.

What actually fits, and what to put food in

Bakeware for an air fryer is a different shopping list from bakeware for an oven. A few ground rules:

• Metal and silicone are the easy choices. Small round cake pans and silicone molds sized to your basket handle the heat and the fan without drama.
• Glass wants caution. Rapid temperature swings are what crack glass, and a small chamber that heats fast is exactly that kind of swing. If you use it, make sure the dish is marked oven safe, start it at room temperature, and follow your air fryer manufacturer's own guidance.
• Nothing may block the airflow. A dish that fills the basket wall to wall turns your air fryer into a slow, bad oven. Leave a gap all the way around.
• Foil and liners need weighting down. Add them after preheating, with food on top, and keep them clear of the element.

Our roundup of air fryer accessories actually worth buying goes through which of these earn their storage space and which are landfill in a nice box.

The five conversion mistakes worth avoiding

1. Converting the time but forgetting the batch size. A sheet pan of vegetables becomes two or three basket loads, not one heroic pile. 2. Skipping the preheat. A cold start quietly adds several minutes and undercuts the time cut you just calculated. 3. Never shaking or flipping. Oven recipes often say nothing about turning food. Air fryer food usually needs it at the halfway mark. 4. Oiling the basket instead of the food. Mist the food. Oil pooling on the coating bakes on, and it is one of the reasons for a smoking air fryer. 5. Trusting the timer over the thermometer. Especially for chicken, the most commonly converted food there is.

Three things that make conversions painless

None of this is mandatory. All of it makes the guesswork shorter.

An instant read thermometer. The single most useful tool for converting recipes, because it removes the only question that really matters. Check current price on Amazon

A refillable oil mister. Converted oven recipes often call for more oil than the air fryer needs, and misting the food gives you even coverage without aerosol propellants building up on the nonstick. Check current price on Amazon

Small round pans and silicone molds. These are what make baked goods and saucy dishes possible at all in a basket. Measure your basket before you buy, because the difference between a six and seven inch pan decides whether it goes in. Check current price on Amazon

If converting keeps turning into three separate batches, the problem is the machine, not the method. Our air fryer finder matches capacity to how you actually cook, and the best air fryers for small kitchens covers the models that add usable space without eating your counter.

FAQ

Do I still need to preheat when I convert a recipe?

Yes, in almost every case. The 20 percent time reduction assumes the food meets hot air immediately. Starting cold gives you a slow ramp at the beginning, uneven browning, and a cook time that drifts back toward the oven figure. Most air fryers preheat in a few minutes, which is a fraction of what an oven takes, so there is very little reason to skip it.

What if my air fryer will not go as high as the recipe?

Run it at your maximum and add time at the end. Plenty of basket models stop around 400F, so a 425F or 450F oven recipe simply cannot be matched. You will get slightly less aggressive browning and a slightly longer cook. For roasted vegetables or reheated leftovers nobody will notice. For a pizza that needs a blistered crust, the oven still wins.

Does the 25F rule apply to fan ovens and Celsius recipes?

Partly. If the recipe was written for a fan or convection oven, the reduction is already baked in, so keep the temperature and just cut the time by about 20 percent. For a conventional Celsius recipe, drop roughly 15C to 20C and take the same 20 percent off the clock.

Can I convert a lasagna or a casserole?

You can, with the right dish and realistic expectations. Use a small oven safe dish that leaves airflow room around it, cover it for most of the cook so the top does not burn before the middle heats through, and uncover at the end to brown. It works. It is also a lot of fiddling for a dish the oven handles comfortably, and reheated leftovers are where the air fryer genuinely beats it.

Why did my converted food burn outside and stay raw inside?

The temperature was too high for the thickness. The fan browns the surface aggressively, so thick items need a lower setting and a longer run rather than the recipe's original heat. Drop another 25F, add time, and check with a thermometer. Cutting the food into smaller, more even pieces solves it outright most of the time.

Do I have to cut the recipe down?

Usually, yes. A basket holds far less than a sheet pan, and cramming it is the fastest way to soggy, unevenly cooked food. Halve or quarter the batch and run it in rounds, or cook the crispy component in the air fryer and the rest in the oven. Dual basket models make this less annoying if you convert full meals regularly.

Does the rule apply to frozen food?

Check the packaging first. Most frozen foods now print air fryer instructions alongside the oven ones, and those are tuned to the product. Apply the rule only if the bag gives oven directions alone, and expect to shake the basket more often than the box suggests.

Will converting recipes make more mess than oven cooking?

A little, and it concentrates in one small basket. Converted recipes often carry more oil than the air fryer needs, which is the main cause of buildup. Trim the oil, mist rather than pour, and keep up with a regular clean. A clean basket also converts more predictably, since baked on residue burns and smokes long before your food is done.

EggBoo Verdict: Subtract 25F, take off 20 percent of the time, check at halfway, and let a thermometer have the final word. That handles the overwhelming majority of oven recipes. Adjust harder for baking, and skip wet batter entirely. Cook in rounds instead of crowding the basket. Get those four things right and the recipe you already love works on the counter, in less time, without the oven heating your kitchen.