Air Fryer Conversion Calculator
Every oven recipe hides a translation problem when you move it to the air fryer. The air fryer is a small, powerful convection oven, so the same 425 degrees for 25 minutes that works in a full-size oven will burn the outside of your food before the inside finishes. The standard fix, backed by university extension services, is simple: drop the temperature by about 25°F and cut the cooking time by roughly 20%.
The Air Fryer Conversion Calculator below does that math for you, and it goes one step further than most converters: it asks whether your recipe was written for a conventional or a fan (convection) oven, because that changes the adjustment. It works in Fahrenheit or Celsius, tells you when to start checking, and flags the 400°F ceiling most home air fryers share.
Quick Answer
Key takeaways
- Conventional oven to air fryer: subtract 25°F (15°C) from the temperature and multiply the time by 0.8.
- Fan or convection oven to air fryer: keep the temperature and multiply the time by 0.9.
- Most home air fryers top out at 400°F, so recipes above that get capped, not converted.
- Converted times are estimates. Start checking three-quarters of the way through, and trust a food thermometer over any chart.
- Quick Answer
- Why the air fryer needs different settings
- The conversion rule, step by step
- Worked example, checked against this exact tool
- Quick conversion chart for common recipes
- When the standard rule breaks down
- What competing converters miss
- Frequently asked questions
- Add This Calculator to Your Website
- References
Why the air fryer needs different settings
An air fryer is essentially a countertop convection oven: a small cooking chamber with a powerful fan sitting close to the food. Because the space is tiny, hot air reaches every surface of your food far faster than in a full-size oven cavity, so the outside browns and crisps before the inside finishes cooking. Running the recipe's original oven settings in the air fryer is the fastest way to get burned edges with a raw center.
The two adjustments that fix this are a temperature drop and a shorter cook time. University of Illinois Extension advises lowering the temperature by 25 to 30°F and cutting the cooking time by 20% when converting a conventional oven recipe to the air fryer. The calculator above applies exactly that rule, and it also handles the case most converters ignore: recipes written for a fan or convection oven, where the temperature needs little or no reduction.
The conversion rule, step by step
The math is simple enough to do in your head, but the oven-type distinction is where people get tripped up. Here is the full procedure the calculator follows:
Identify the oven type. Read the recipe. Unless it says "fan," "convection," or gives a lower fan-oven temperature in parentheses, assume conventional.
Apply the temperature rule. Conventional recipe: subtract 25°F (about 15°C). Fan or convection recipe: keep the temperature as written. Round to the nearest 5 degrees, since air fryer dials do not do finer steps.
Shorten the time. Multiply the oven time by 0.8 for conventional recipes, or by 0.9 for fan-oven recipes. Plan to start checking at three-quarters of that converted time.
Worked example, checked against this exact tool
Enter the pre-filled defaults (425°F, 25 minutes, conventional oven) and click Calculate. Here is what the tool returns, verified against the underlying code:
| Figure | Value |
|---|---|
| Oven recipe | 425°F for 25 minutes |
| Air fryer temperature | 400°F (425 − 25) |
| Air fryer time | 20 minutes (25 × 0.8) |
| Start checking at | 15 minutes (75% of 20) |
| Time saved | 5 minutes |
Switch the unit to Celsius with a 200°C, 30-minute conventional recipe and the calculator gives 185°C for 24 minutes. The Celsius drop is 15°C, rounded to the nearest 5, which matches the extension guidance. Try the fan/convection oven type with 425°F and 25 minutes: the temperature stays at 400°F after the cap and the time becomes about 23 minutes (25 × 0.9).
Quick conversion chart for common recipes
For everyday roasting and crisping, these conventional-oven conversions cover the temperatures most recipes use. The calculator is more precise for unusual values, but the chart is handy on the fridge door:
| Oven (conventional) | Air fryer temp | Oven time | Air fryer time |
|---|---|---|---|
| 300°F (150°C) | 275°F (135°C) | 15 min | 12 min |
| 325°F (165°C) | 300°F (150°C) | 20 min | 16 min |
| 350°F (175°C) | 325°F (165°C) | 25 min | 20 min |
| 375°F (190°C) | 350°F (175°C) | 30 min | 24 min |
| 400°F (205°C) | 375°F (190°C) | 20 min | 16 min |
| 425°F (220°C) | 400°F (205°C) | 25 min | 20 min |
When the standard rule breaks down
The 25°F / 20% rule is a starting point, not a guarantee, and a few situations need different handling. Wet batters (like beer-battered onion rings) drip through the basket and never crisp; they belong in a deep fryer. Very large roasts block airflow and cook unevenly, so a whole turkey is better left to the oven. A crowded basket steams instead of crisps: cook in a single layer and work in batches, which matters more than any setting.
Frozen foods deserve special care. Many frozen products print air fryer directions on the package, and the USDA advises following the manufacturer's instructions when they exist. The calculator is for recipes written for a conventional oven, not for overriding the bag. If you are also changing the portion size, scale the recipe first with a recipe serving size calculator and then convert the adjusted time. And if the recipe gives the time in hours, turn it into minutes with a time conversion calculator before entering it.
For weekly cooking, the air fryer earns its counter space on speed: batch-cooking proteins and vegetables at converted settings is one of the cheapest ways to prep lunches. If you are costing out a week of home-cooked meals, a meal prep cost calculator pairs well with these settings.
What competing converters miss
We tested the top-ranking air fryer converters before writing this page. The pattern is consistent: most apply the temperature drop and the time cut, and stop there.
No oven-type distinction. The most common converter error is applying the full 25°F reduction to recipes that were already written for a fan or convection oven. Those recipes are already closer to air fryer behavior, so the full reduction undershoots. This calculator asks for the oven type and uses a smaller adjustment for fan-oven recipes.
No temperature ceiling. A surprising number of converters will happily tell you to air fry at 425°F. Most home air fryers max out at 400°F, and a setting you cannot dial in is not a setting. Ours caps at 400°F and says so.
No "check at" time. Converters give you a single time and leave you to guess when to peek. Every air fryer model runs slightly hot or cool, and Illinois Extension specifically advises shaking the basket or flipping food midway. The "start checking at" row builds that habit into the result.
Fahrenheit-only thinking. Several popular converters are °F-only, which is no help for the large share of recipes written in Celsius. The unit toggle converts in both directions with the 15°C rule baked in.
Frequently asked questions
For a conventional oven recipe, lower the temperature by 25°F (about 15°C) and cook for 80% of the oven time. University of Illinois Extension gives this as the standard rule: a 400°F-for-30-minutes recipe becomes 375°F for about 24 minutes. For a fan or convection oven recipe, keep the temperature and cut the time by about 10%.
Usually yes, unless your manual says otherwise. University of Illinois Extension advises preheating for about 3 minutes. Skipping the preheat can add several minutes to the effective cook time and throw off converted times, especially on short recipes.
For most foods, yes. Illinois Extension recommends shaking the basket or using tongs to flip foods in the middle of the cooking time, and warns against overcrowding the basket, which prevents food from cooking evenly. Single-layer cooking with one flip beats any setting adjustment.
An air fryer is already a small, intense convection oven, so a fan-oven recipe needs a smaller adjustment: keep the same temperature and trim the cooking time by about 10%. The calculator has an oven-type selector for exactly this. Applying the full 25°F reduction to a fan-oven recipe usually undershoots the temperature.
Use a food thermometer in the thickest part. Per the FoodSafety.gov chart, poultry is safe at 165°F, ground meat at 160°F, beef, pork, and lamb steaks and chops at 145°F with a 3-minute rest, and fish at 145°F. Converted settings estimate browning, not doneness, so the thermometer is the final word.
Set it to 400°F and rely on the shorter cook time. Most home air fryers top out at 400°F, and the calculator caps converted temperatures there automatically. Start checking at the "start checking at" time, since the lower temperature with intense airflow still cooks faster than the oven would.
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References
- University of Illinois Extension, "Kitchen Appliances: Air Fryers" (PDF) - cooking tips including the 25-30°F temperature reduction, 20% time cut, 3-minute preheat, and basket-shaking guidance. Illinois Extension: Kitchen Appliances - Air Fryers. Accessed October 19, 2026.
- University of Illinois Extension, "A New Way to Fry" - air fryer cooking guidance and recipes from a nutrition and wellness educator. Illinois Extension: A New Way to Fry. Accessed October 19, 2026.
- Iowa State University Extension and Outreach, "Air Fryer Adventures - Part 2" - practical air fryer cooking notes including not overloading racks for even cooking. Iowa State Extension: Air Fryer Adventures. Accessed October 19, 2026.
- FoodSafety.gov, "Cook to a Safe Minimum Internal Temperature" - USDA safe minimum internal temperature chart (poultry 165°F, ground meat 160°F, steaks 145°F with 3-minute rest, fish 145°F). FoodSafety.gov Safe Minimum Cooking Temperature Chart. Accessed October 19, 2026.