Air fryer conversion: how to cook oven recipes in an air fryer

The usual rule of thumb is to lower an oven recipe's temperature by about 25 °F (roughly 15 °C) and cut the time by about 20%, then check early. A recipe at 400 °F for 25 minutes becomes about 375 °F for 20 minutes; 200 °C for 25 minutes becomes about 185 °C for 20. It is a starting point, not a law, because air fryers vary widely. The air fryer converter does the arithmetic in either direction and tells you when to start checking.

Why air fryers cook faster

An air fryer is a small convection oven. A heating element sits close to the food and a powerful fan drives hot air around it in a compact space, so surfaces dry and brown faster than in a large oven, where air moves more slowly and the food sits further from the heat. The basket lets air reach the underside too. That is why chips and wings crisp so well, and also why the outside of a food can finish before the middle if the temperature is too high.

The conversion rule

Start from the conventional oven settings in the recipe, then:

• Temperature: reduce by about 25 °F, which is about 14 °C; many UK guides round this to 20 °C. The converter uses 25 °F and rounds to the nearest 5 degrees.
• Time: reduce by about 20%, so multiply by 0.8.
• Check early: look at about three-quarters of the new time, and shake or turn the food halfway.

Worked examples: 425 °F for 30 minutes becomes 400 °F for about 24 minutes, checking from 18. 180 °C for 40 minutes becomes about 165 °C for 32 minutes, checking from 24. The first time you make a dish, treat it as a test run and note what your machine actually needed.

Fan ovens and the reverse conversion

Many British and European recipes give a fan oven temperature, which is already about 20 °C lower than the conventional setting. Converting that figure again can undercook food, so either start from the conventional temperature or reduce a fan temperature only slightly. The oven temperature converter translates between conventional, fan, gas mark and Fahrenheit. The rule also runs backwards for air fryer recipes you want to make in an oven: add about 25 °F and divide the time by 0.8, so 180 °C for 12 minutes becomes about 195 °C for 15 minutes in a preheated oven.

What converts well and what does not

The rule works best for foods that suit dry, fast heat: chips and potato wedges, chicken wings and thighs, roasted vegetables, breaded or frozen snacks, sausages, fish fillets and reheating leftovers. It is less reliable for:

• Wet batters, which drip through the basket before they set.
• Cakes and bakes, where the top can brown before the centre cooks; lower the temperature further and cover the top if needed.
• Large roasts, which may not fit with space for air to move, and brown outside long before the centre is ready.
• Very light foods, such as leafy greens, which the fan can blow around.

For long, slow, wet cooking, the opposite end of the scale, the slow cooker converter adapts oven recipes instead.

Getting it right first time

Do not overcrowd the basket: a single layer with gaps cooks evenly, while a heap steams. Cook in batches if necessary; the second batch is often a little quicker because the fryer is already hot. Preheat for a few minutes if your model's manual recommends it. A light coating of oil helps browning. Parchment liners must be weighed down by food, or the fan can lift them onto the element. If a frozen product gives air fryer instructions on the pack, follow those rather than converting the oven times.

Checking food is cooked

A shorter time is only safe if the inside is cooked, so use a food thermometer for meat. US guidance gives 165 °F (74 °C) for all poultry, 160 °F (71 °C) for minced meat, and 145 °F (63 °C) plus a 3-minute rest for whole cuts of beef, pork and lamb. The meat cooking time calculator lists internal temperatures by cut and doneness, the temperature converter switches between °F and °C, and How long to cook a turkey: roasting times, thawing and safe temperatures explains where to place a thermometer. Follow the official food safety guidance where you live.