Air fryers are creating a lot of buzz because they claim to cook your foods to a crackly crunch without the fat. But are the gadgets worth the hype, or just a lot of hot air? Consumer Reports put them to the test.

An air fryer works by circulating hot air around food that’s suspended in a basket. It’s essentially a countertop convection oven that cooks your food from different directions.

What makes them healthier is the fact many recipes call for foods to be tossed with a bit of oil, rather than being fully immersed when you use a traditional fryer.

Consumer Reports tested seven appliances, and although they appear similar from the outside, there were some real differences.

“One big difference you’ll see is basket size. Some are so small they require you to cook in batches and that’s not as good when you’re cooking for the whole family,” said Sara Morrow, Consumer Reports home editor.

The Nu-Wave air fryer costs around $190 and was the largest one tested, with a 5.7 litre capacity. It has easy-to use controls, but the machine is a little noisy, comparable to a microwave.

Consumer Reports calls the Farberware HF-919B model a best buy. It costs about $70, and is one of the quietest they tested. The controls are fairly easy to see and use and it holds three litres. But the nooks and crannies in the food basket make it a little tough to clean.

The Purify fryer from Black+Decker has temperature settings printed so tiny they’re difficult to read. And the small basket holds just two litres – fine if you’re not cooking very much, but you’ll have to do multiple batches if the kids bring their friends for nuggets.