Last reviewed on 8 June 2026.
Table of Contents
Short, practical answers to the questions people ask most about air fryers. For anything that needs more depth, each answer links to the full guide. If a question you have isn't here, send it through our contact page and we'll add it.
Getting Started
Do you need to preheat an air fryer?
Not always, but it helps for foods you want crisp — frozen items, chips, and meat. A 2–3 minute preheat at the cooking temperature gives a better sear and more even results. For longer bakes like cakes, preheating is less important. Many smaller models heat up so fast that preheating makes little difference.
Do you need oil in an air fryer?
You need far less than frying, but a light coating still helps. Tossing vegetables or chips in 1–2 teaspoons of oil improves browning and stops sticking. Naturally fatty foods like sausages, bacon, and chicken thighs need no added oil at all. Use a brush or a pump sprayer rather than aerosol cans, which can damage the non-stick coating.
How do you stop food sticking to the basket?
Lightly oil the food (not just the basket), don't overcrowd, and let food release naturally before flipping — it usually unsticks itself once it has browned. For delicate or sticky items, a perforated parchment liner helps. Keeping the basket's non-stick coating in good condition matters too, so avoid metal utensils and aerosol sprays.
Can you open an air fryer while it's cooking?
Yes — opening a basket-style air fryer to check, shake, or flip food is completely safe and expected. It pauses automatically when you pull the drawer out and resumes when you slide it back. You lose a little heat, so close it promptly, but checking food is far better than overcooking it.
Cooking and Temperatures
How do I convert an oven recipe to an air fryer?
As a starting point, lower the temperature by about 20°C (25°F) and cut the time by roughly 20%, then check early. Air fryers cook faster and more intensely than ovens, so the first time you make something, watch it closely. See our guide to converting oven recipes for the full method and the recipes that don't translate cleanly.
What is 180°C in an air fryer in Fahrenheit?
180°C is about 355°F, which is normally rounded to 350°F on machines that display Fahrenheit. The other common ones are 160°C ≈ 320°F, 190°C ≈ 375°F, and 200°C ≈ 400°F. Our temperature conversion chart lists every value in both directions plus gas marks.
Why is my food not crispy?
Usually one of four things: the basket is overcrowded, the food was wet, there wasn't enough oil, or the temperature was too low. Pat food dry, cook in a single layer with space around each piece, toss in a little oil, and raise the temperature by 10–15°C for the last few minutes if needed.
Do you need to flip or shake food?
For most things, yes. Shaking the basket or flipping food halfway through gives even browning, because the air, while fast-moving, still hits the top surface hardest. Loose items like chips and vegetables should be shaken; larger items like chops and fillets should be flipped once.
Can you cook frozen food in an air fryer?
Yes — this is one of the things air fryers do best, with no thawing needed. Frozen chips, nuggets, fish, and vegetables cook straight from the freezer, often crisper than in an oven. See our frozen foods guide for times, and shake the basket more often than you would for fresh food.
Can you put liquid or batter in an air fryer?
Thin batters and loose liquids are a problem — the fast airflow blows wet batter around before it sets, so a traditional battered item won't work. Thick batters in a tin (like cake or muffin batter) are fine because they're contained. For coatings, use breadcrumbs or a dredge rather than a wet batter.
Safety and What's Allowed
Can you put foil or parchment paper in an air fryer?
Both are fine if used correctly: keep them weighted down by food so they can't blow into the heating element, and never preheat with an empty liner inside. Don't cover the whole base — the perforations need to stay clear for air to circulate. Avoid foil with very acidic foods like tomatoes or citrus, which can react with it.
Can you put glass or ceramic dishes in an air fryer?
Yes, as long as they're oven-safe and fit with room for air to move around them. Tempered, oven-rated glass (such as Pyrex) and ceramic ramekins both work well for baking and reheating. Avoid sudden temperature changes — don't put a cold glass dish into a fully preheated machine — and check our bakeware guide for the full list.
Is the smoke from my air fryer dangerous?
Light smoke is usually just fat hitting the hot element — add a tablespoon of water to the drawer under fatty foods to stop it. Persistent or acrid smoke means built-up grease or a misplaced liner, so stop and clean it. If you ever smell burning plastic or electrical smells, switch it off at the wall and inspect it.
Are air fryers safe to leave unattended?
They have automatic shut-off timers and are generally safe, but like any heating appliance it's best not to leave one running while you're out of the house. Keep the vents clear, sit it on a heat-resistant surface with space behind it, and never run it covered or pushed against a wall. See our safety guide for placement details.
Where should I place my air fryer on the counter?
On a stable, heat-resistant surface with at least 12–15 cm (5–6 inches) of clearance behind and above it for the hot exhaust. Keep it away from walls, cabinets, and anything flammable like paper towels or curtains, and never run it directly under a low wall cabinet.
Cleaning and Maintenance
How often should you clean an air fryer?
Wipe the basket and drawer after every use once they've cooled — it takes a minute and stops grease building up. Do a deeper clean of the interior and heating element every week or two depending on how often you cook fatty foods. Our cleaning guide covers baked-on grease and the element.
Can you put the basket in the dishwasher?
Many baskets are dishwasher-safe, but check your manual — repeated dishwasher cycles can shorten the life of the non-stick coating. Hand-washing in warm soapy water with a soft sponge is gentler and usually quicker than running a full cycle for one part.
How do you clean baked-on grease?
Soak the basket in hot soapy water for 10–15 minutes to soften the residue, then use a soft brush or non-scratch sponge. For stubborn spots, a paste of baking soda and water works without scratching. For the heating element, wait until it's cool and wipe it with a damp cloth — never submerge the main unit.
Why is my air fryer smoking when it's empty?
Usually leftover grease on the element from a previous cook burning off. Let it cool, wipe the element and interior, and run it empty for a few minutes to clear any residue. If a brand-new air fryer smokes a little on first use, that's normal manufacturing residue and stops after a cycle or two.
Buying and Sizing
What size air fryer do I need?
Roughly: 2–4 litres for one or two people, 5–6 litres for a family of three or four, and 7 litres or more (or a dual-basket model) for larger households or batch cooking. Capacity in litres doesn't all translate to usable space, so check the basket dimensions too. Our size guide breaks it down by household.
Is a basket or oven-style air fryer better?
Basket models are more compact, heat up faster, and tend to crisp small batches better; oven-style models hold more, let you cook on multiple racks, and often add functions like rotisserie. It comes down to counter space and how much you cook — our basket vs oven comparison goes through the trade-offs.
How much does it cost to run an air fryer?
Far less than a full oven for small portions, because there's a much smaller space to heat and cooking times are shorter. A typical cook uses only a few pence/cents of electricity. For longer cooks or large batches the saving shrinks. See our energy use guide for how to estimate cost per cook.
Are expensive air fryers worth it?
The core cooking performance of a mid-range model is often very close to a premium one. You pay more for capacity, build quality, presets, dual baskets, and quieter fans. If you cook often or for a family those extras can be worth it; for occasional use a well-reviewed budget model is usually enough. Our buying guide covers what actually matters.
Can an air fryer replace my oven?
For one or two portions it often can — it's faster, cheaper to run, and crisps well. But it can't match an oven's capacity, and large roasts, big bakes, or cooking several dishes at once still need the oven. Most people end up using both, with the air fryer handling the quick everyday jobs.