Oven to Air Fryer Conversion
Oven to air fryer conversion comes down to two adjustments: lower the temperature by about 20 °C and shorten the cooking time by 20–25 %, measured against a fan oven. This guide gives you the rule, a table that matches gas mark, conventional oven, fan oven and air fryer temperatures, a chart of common foods with the times used on our recipe pages, and the cases where it is better not to convert at all.
The rule of thumb
An air fryer is a small, powerful fan oven. The heating element sits close to the food and the fan moves hot air around a basket only a few centimetres deep, so heat reaches the surface faster than in a large oven cavity.
- Temperature: take the fan oven temperature and subtract about 20 °C.
- Time: multiply the oven time by 0.75–0.8, so a 40-minute oven recipe becomes roughly 30–32 minutes.
- Check early: start testing at about two thirds of the new time. You can always add a few minutes, but you cannot undo overcooking.
Treat the result as a starting point. Basket size, how full it is and how cold the food was all change the outcome. The air fryer cooking times chart lists tested timings for individual foods, which is always better than a calculation.
Gas mark, conventional oven, fan oven and air fryer
Recipes written for British kitchens use gas marks or conventional temperatures, and many ovens are fan ovens. Always check which one a recipe means, because the gap between a conventional and a fan oven is about 20 °C. Work from the fan oven column, then subtract another 20 °C for the air fryer.
| Gas mark | Conventional °C | Fan oven °C | Air fryer °C |
|---|---|---|---|
| 2 | 150 | 130 | 110 |
| 3 | 160 | 140 | 120 |
| 4 | 180 | 160 | 140 |
| 5 | 190 | 170 | 150 |
| 6 | 200 | 180 | 160 |
| 7 | 220 | 200 | 180 |
| 8 | 230 | 210 | 190 |
| 9 | 240 | 220 | 200 |
Most air fryers run from about 80 or 100 °C up to 200 °C, so gas mark 9 is as high as you can go. Where a recipe calls for something hotter, use 200 °C and add a few minutes.
Time conversion at a glance
| Oven time | Air fryer time |
|---|---|
| 10 minutes | 8 minutes |
| 20 minutes | 15–16 minutes |
| 30 minutes | 22–24 minutes |
| 45 minutes | 34–36 minutes |
| 60 minutes | 45–48 minutes |
| 90 minutes | 68–72 minutes |
Conversion chart for common foods
The air fryer column uses the times from our recipe pages. The oven column shows a typical fan oven time for comparison. In practice the saving is closest to the 20–25 % rule for joints and bakes; small pieces such as vegetables and chips often save far more.
| Food | Fan oven | Air fryer |
|---|---|---|
| Medium jacket potato, 250 g | 200 °C, 1 hr to 1 hr 15 min | 200 °C, 40–45 min |
| Chunky homemade chips, 1.5 cm | 200 °C, 35–40 min | 200 °C, 22–25 min |
| Straight-cut frozen chips | 200 °C, 20–25 min | 200 °C, 15–18 min |
| Pork sausages | 200 °C, 25–30 min | 180 °C, 12–15 min |
| Brussels sprouts, halved | 200 °C, 25 min | 190 °C, 12–14 min |
| Honey carrots, batons | 200 °C, 25–30 min | 190 °C, 15–18 min |
| Bone-in chicken thighs | 200 °C, 35–40 min | 190 °C, 24 min |
| Whole chicken, 1.5 kg | 180 °C, 1 hr 20 min | 180 °C, 55–60 min |
| Turkey crown, 1.5 kg | 180 °C, 1 hr 15 min | 180 °C, 55–60 min |
| Roast beef, 1 kg, medium | 180 °C, 1 hr | 180 °C, 45 min |
| Half leg of lamb, 1 kg, pink | 180 °C, 55–60 min | 180 °C, 40–45 min |
| Homemade lasagne | 180 °C, 40–45 min | 180 °C, 28–30 min |
| Frozen 20 cm pizza | 200 °C, 12–15 min | 180 °C, 8–10 min |
| Basic muffins | 180 °C, 18–20 min | 160 °C, 14 min |
| Chocolate chip cookies, 40 g | 170 °C, 10–12 min | 160 °C, 8–10 min |
Notice that the air fryer temperature does not always drop by 20 °C. Chips, wedges and fish fingers brown best at 200 °C because the pieces are small and thin. Large joints and bakes keep the 180 °C or 160 °C of the oven because the outside would colour long before the middle is cooked at a higher heat. Cook starchy foods such as potatoes and chips to a golden yellow rather than dark brown, as the Food Standards Agency advises in its Go for Gold guidance.
Worked examples
A recipe says 40 minutes at 180 °C fan. Lower the temperature to 160 °C and multiply the time by 0.75, which gives 30 minutes. Start checking at 20–25 minutes.
A recipe says 35 minutes at 200 °C conventional. That is 180 °C fan, so set the air fryer to 160 °C. Thirty-five minutes becomes about 26 minutes, so look at it from 18 minutes.
A recipe says 25 minutes at gas mark 6. The table gives 160 °C. Twenty-five minutes becomes about 20 minutes, with a first check at 14–15 minutes.
A pack says 20 minutes at 200 °C fan. For frozen food, the pack is a good guide: try 180 °C for 15 minutes, then add time in two-minute steps.
Converting an air fryer recipe back to the oven
For air fryer to oven conversion, reverse the rule: add about 20 °C for a fan oven and allow roughly a quarter to a third more time. A 12-minute air fryer recipe becomes about 15–16 minutes in the oven. Add another 20 °C again for a conventional oven without a fan.
When not to convert
Some dishes depend on the oven and should stay there:
- Large joints and big birds that do not fit the basket with at least 2 cm free above the food.
- Loose batters and liquids, such as large Yorkshire pudding trays, stews, soups and casseroles, which spill or splatter in a fan-driven basket.
- Big cakes in deep tins, where the outside sets before the middle bakes. Small bakes such as muffins work well.
- Several trays at once. One layer in the basket cooks properly; two overlapping layers steam instead of crisp.
- Very light foods such as loose leaves, which blow about in the fan.
- Anything needing a lid-on, slow simmer or a water bath.
Oven-style air fryers with shelves behave more like a small fan oven, so reduce the temperature by only about 10 °C and keep the time closer to the oven recipe.
Common conversion mistakes
- Trusting the clock. Use a probe thermometer for meat. Poultry and minced meat should reach 75 °C, and pork joints should be cooked through with no pink meat.
- Overfilling the basket. Convert the time for a single layer; for more food, cook in batches.
- Forgetting to preheat. Three minutes at the set temperature gives the first batch the same start as the oven.
- Skipping the shake or turn. Most foods need one or two turns for even browning.
- Not checking leftovers. Reheat until steaming hot all the way through, around 75 °C, before serving.
Frequently asked questions
How do you convert oven to air fryer cooking times?
Subtract 20 °C from the fan oven temperature and shorten the time by 20–25 %. Start checking about two thirds of the way through the new time.
Is there an air fryer conversion calculator?
You do not need one for most recipes. Multiply the oven time by 0.75–0.8 and use the temperature table above. The conversion chart and the air fryer cooking times page save the sums for common foods.
What is the air fryer temperature for gas mark 6?
Gas mark 6 is 200 °C conventional or 180 °C fan, so set the air fryer to about 160 °C. Shorten the time by roughly a quarter.
Do I convert a conventional oven differently from a fan oven?
Yes. A conventional oven runs about 20 °C hotter than the same setting on a fan oven. Convert to fan first, then subtract another 20 °C for the air fryer.
Can I use the oven time for frozen food packs?
Yes, as a starting point. Reduce the temperature by 20 °C, cut the time by around a quarter and follow the pack for the safe cooking instruction. See the frozen chips page for examples.
Does everything cook faster in an air fryer?
Not everything. Small, thin and dry foods gain the most. Dense, large or wet dishes save less time, and some are better left in the oven.
