The litre figure on an air fryer is the most misread number in the kitchen: it describes the basket, not the food — and overfilling is precisely how an air fryer stops working.
From a tested field of 31 air fryers, here is what the testing actually establishes.
What an air fryer is, mechanically
A heating ring warms the air; a fan circulates it evenly around the chamber, so food is continuously bathed in hot air — crisping quickly with little or no fat. Temperature is precisely adjustable on most models, typically 80 to 200 °C, and a 40 °C mode doubles usefully as a keep-warm function.
The honest comparison: an air fryer is a small convection oven — but not quite. An oven usually has two heating elements, top and bottom; every tested air fryer has one, and the much smaller chamber makes the air circulation stronger. That is what produces crispier results. It is also more space-efficient, and it sheds less heat into the kitchen.
The difference from a deep fryer is the point of the category, and the chips numbers make it concrete: air-fried chips from fresh potatoes carry about 3 g of fat, frozen ones about 6 g — where deep-fried chips carry far more. Most dishes need at most a teaspoon of oil, and many none at all.
The capacity rule that stops disappointment
Capacity is stated as basket volume: small models around four litres, large ones up to ten. But the volume is not the amount of food. In a four-litre basket, cook no more than a kilo of chips — beyond that the air cannot circulate and the food cooks unevenly. That single rule explains most bad first experiences with the category.
Size to the household, not the aspiration: around four litres serves singles and couples; families want the larger baskets or a dual-drawer design.
The picks
Best overall — Cosori Turbo Tower Compact. A dual air fryer in a tower design that scored very well in every category. The build feels genuinely high-quality — a metal inner housing — and the two 4.3-litre baskets are ceramic-coated and dishwasher-safe. Crucially, each basket has its own heating element, so the two drawers genuinely cook independently rather than sharing heat. The tower layout is the small-kitchen answer: a footprint of just 43 x 28 cm at 27 cm tall, where dual-drawer rivals sprawl sideways.
Best value — Medion Life X10 XL. It beat considerably more expensive rivals in the comparison. The footprint is a modest 27 x 31 cm, the capacity a correspondingly modest 5 litres — and the efficiency is the point: at 1,500 watts it covers a wide 40 to 230 °C temperature range with restrained power consumption.
Top alternative — Cosori Iconic. The looker of the field: almost entirely stainless steel with rounded 1950s-diner corners, a 6.2-litre basket in PFAS-free ceramic that still goes in the dishwasher, and a temperature span of 30 to 230 °C that stretches from keep-warm to properly crisp. Chips and baked goods both came out very well.
Best dual-basket alternative — Russell Hobbs Satisfry Dual Basket. The familiar side-by-side twin-drawer format done well.
Best with steam — Philips NA555/00 Steam Airfryer. Air fryer and steamer in one: a six-litre main chamber plus a three-litre secondary compartment that runs independently, with moisture fed from an integrated water tank — the route to foods that should stay moist inside their crust. Baskets and inserts are dishwasher-safe, a recipe book is included, and there is deliberately no Wi-Fi or app.
Hottest — Ninja Crispi Pro. The pick for maximum crisp: it reaches 240 °C, beyond the field's typical 200 °C ceiling, which changes what browning is possible.
For big households — Stillstern multifunction air fryer, the large-portion specialist.
Easiest to live with — Philips Airfryer Combi 7000 Series XXL. The usability pick at family scale.
For singles — Ninja Crispi. Small, simple, and honest about its portion size.
Getting crispy results
Three habits do more than any accessory: do not overfill (the rule above), shake or turn partway through so every surface meets the moving air, and use the precise temperature control rather than defaulting to maximum — the difference between dried-out and crisp is usually ten degrees and a shake, not more power.
Before you buy
Four questions. How many people, honestly? Four litres per one-to-two people; dual baskets or XXL beyond that. Worktop width or height? Tower designs buy capacity vertically. Do you want steam or extreme heat? Each has exactly one specialist here. And will the baskets fit your dishwasher? — coating and cleanability decide whether it stays in use after the novelty month.
Air fryers sit alongside our best multicookers guide, and the countertop-oven end of the spectrum appears in our best pizza ovens coverage.
