Ninja
Foodi MAX AG551UK
Test score
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We test each low-fat fryer in exactly the same way, so that you can easily compare them to find out which is the best one for you.
Our independent reviews will tell you everything you need to know about an air fryer before you buy one, from how good the chips are, to how easy it is to use and keep clean - plus how quickly it will get dinner on the table.
Our reviews answer the most crucial questions about air fryers:
Find out which fryers aced our tough tests by checking out our air fryer reviews.
We cook frozen chips in each air fryer. The best models turn out evenly cooked chips with a crispy golden brown exterior and fluffy insides. We mark down air fryers that produce greasy, soggy, undercooked or overcooked chips.
Even cooking is also important - fryers that produce a mixed bag of part-raw and part-burnt chips get marked more harshly.
When we asked Which? members what they cook most often in their air fryer, chips were the most popular option by far. But they aren't just for chips, so we also test how well they cook another food that's popular among Which? members: chicken.
We cook chicken drumsticks in each air fryer and rate how evenly cooked and moist they are, to ensure you'll end up with a delicious, evenly cooked meal.
To prevent you having to hang around waiting for your food to cook, we time how long it takes each low-fat fryer to produce golden brown chips. The quickest air fryers take 20 minutes to cook four portions of chips, and you don't have to wait for them to heat up. The slowest, on the other hand, take over 45 minutes.
For comparison, we've found that if you factor in the time takes for them to heat up, ovens take between 21 and 39 minutes to cook a similar amount of food, while deep-fat fryers take 15-31 minutes.
We calculate how much energy (in kWh) each air fryer uses while cooking, so you don't end up with an energy-guzzling fryer that adds too much to your electricity bills. The differences aren't huge, though; if you cooked four portions of chips three times a week for year, the most energy-efficient air fryer would cost you £14.33, while the least efficient would set you back £18.43.
For truly fuss-free chips, you need a fryer that is simple to use. We assess how user-friendly the controls and instructions are, and how easy it is to open and close the lid to add or get to your food.
We rate each fryer on how straightforward the cooking process is, including whether whether you need to stir the food while you're cooking, if it's easy to keep an eye on the chips as they cook and whether the fryer switches off automatically once it's done. We also check how hot the fryer gets during cooking, so you know if you need to take care when getting food in and out.
Finally, we assess how easy it is to clean both the inside and outside of the fryer, and whether you can store it easily.
The results of all these tests are combined to work out the overall score for each air fryer. We know that some tests are more important than others, so we give extra weight to the ones that matter most - such as how good the chips taste and how evenly they're cooked. Here's how the overall score breaks down:
Air fryers scoring 75% or above are considered first-rate fryers and are rated as Best Buys, while those scoring 45% or below are Don't Buys that are best avoided.
See Best air fryers 2022 for tips and advice to help you choose an air fryer, plus the top Best Buy air fryers we've tested.
In January 2020, we updated our testing to account for the increasing variety of air fryers now available.
Our ease of use testing now includes an assessment of how versatile each air fryer is, taking into account the different programs and attachments available. We also assess how easy it is to watch the cooking process through a window.
For the cooking testing, we changed the chips we use from freshly cut ones to frozen ones and the chicken we use from breasts to drumsticks, to better mirror what you will really cook in it.
For the first time we also assessed each air fryer's build quality, commenting on how sturdy the controls, attachment, lid and hinges feel.
In November 2020, we updated the way we evaluate air fryers. This meant that we raised the Best Buy threshold to 75%, causing some models to lose their Best Buy status.