140°C Oven to Air Fryer: Use 120°C
Drop the temperature by 20°C and cut the time by 20% as a starting point.
Published by the RecipeAirFryer editorial team · How we source times · Updated
Times and temperatures come from our reviewed cooking database. Explanatory text on each page is generated from that entry so the numbers stay consistent.
If a recipe says 140°C, set a typical basket air fryer to 120°C (120°C / 248°F) and plan on about 80% of the oven time. At this oven setting people usually cook slow casseroles, meringues, drying citrus, proving-adjacent warming. The 20% rule is a starting point; Colour is not the test at this heat. If they pick up colour, the basket is too hot.
How to convert 140°C to an air fryer
- 1Read the oven recipe: it calls for 140°C (140°C / 284°F).
- 2Preheat the air fryer to 120°C (120°C / 248°F), not 140°C.
- 3Multiply the oven minutes by 0.8. Example: a tray of meringues that would sit 60 minutes in the oven becomes about 48 minutes at 120°C, checking that they dry rather than brown.
- 4Cook in a single layer and check early. Colour is not the test at this heat. If they pick up colour, the basket is too hot.
Conversion chart
| Oven time at 140°C | Air fryer time at 120°C |
|---|---|
| 10 min | 8 min |
| 15 min | 12 min |
| 20 min | 16 min |
| 25 min | 20 min |
| 30 min | 24 min |
| 40 min | 32 min |
| 45 min | 36 min |
| 60 min | 48 min |
What 140°C is usually used for
In a conventional oven, 140°C is the setting for slow casseroles, meringues, drying citrus, proving-adjacent warming. Converting that heat without thinking about the food is why people burn cookies or undercook a joint.
Worked example: a tray of meringues that would sit 60 minutes in the oven. In the air fryer that is about 48 minutes at 120°C, checking that they dry rather than brown.
Why the temperature drops
An oven heats mostly by radiation from its elements and by slow convection. An air fryer is a small chamber with a fan driving air across the food at speed, so heat transfers into the surface much faster at the same dial setting.
That is why 140°C in an air fryer would over-brown the outside before the middle caught up. Setting it to 120°C instead gives you the same finish in less time.
What to watch at 120°C
Colour is not the test at this heat. If they pick up colour, the basket is too hot.
Dense items such as a whole chicken may need close to the original oven time because heat still has to travel to the centre. Go by internal temperature, not only the converted clock.
Gas mark 1 in an air fryer
140°C is roughly gas mark 1. If your recipe is written in gas marks, convert to 140°C / 284°F first, then apply the same drop to get 120°C / 248°F in the air fryer.
Frequently Asked Questions
What is 140°C in an air fryer?
120°C, which is 120°C / 248°F. Reduce the cooking time by about 20% as well, then check early.
What foods are usually cooked at 140°C?
slow casseroles, meringues, drying citrus, proving-adjacent warming. Example conversion: a tray of meringues that would sit 60 minutes in the oven becomes about 48 minutes at 120°C, checking that they dry rather than brown in the air fryer.
Why not just use 140°C in the air fryer?
You can, but the outside will brown or burn before the inside is cooked. The fan transfers heat into the food far faster than an oven does, so the lower setting gives a more even result.
Do I need to preheat the air fryer?
A 2-3 minute preheat helps for anything breaded, frozen or that you want crisp. For longer cooks it makes little difference.