One-minute review

Indoor grills have come a long way since the George Foreman. Ninja is one of the biggest names in indoor grills and other cooking appliances, and it’s introduced an updated version of its indoor grill and air fryer combo; the Ninja Foodi Smart XL 6-in-1 Indoor Grill & Air Fryer with Built in Thermometer, 2nd Generation, DG551 (we’ll refer to it as the ‘second-gen’ model throughout this review to avoid confusion with the original). Despite the name, it does more than grill and air-fry – it also roasts, bakes, dehydrates, and broils.

There are only minor differences, like weight, size, and cord length, between the original model and this second-gen version. The most important functions – like the Smart Cook System, built-in thermometer, and ability to cook frozen food – remain the same. A new design appears to be the main feature of the upgrade.

The Smart XL 6-in-1 can cook large quantities of food at the same time, making it great for families or for batch-cooking our testing, we discovered how easy it is to get a great char on meats in less than 25 minutes, and found the air crisper feature to work better than Ninja’s best air fryer. If you don’t mind cooking with an oil that isn’t olive oil, we think you’ll be satisfied with this appliance.

Ninja has priced the second-gen Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer more competitively than the original model. If it can design an appliance that can grill and fry foods at different temperatures at the same time within one spacious indoor grill/air fryer,  it would really have a winner on its hands. That said, this product beats out other indoor grills and air fryers from competing brands like PowerXL and Gourmia.

Price and availability

  •  List price: $279
  •  Previous version is still available in AU, US, and UK 

The second-gen Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer is an upgraded version of the original model bearing the same name in the US. Currently the new model is only available in the US; the previous version is still sold by Ninja in the US, UK, and Australia – you can read our Ninja Foodi MAX Health Grill & Air Fryer (AG551UK) review for reference, if you need.

The differences between the two models are mostly cosmetic. The second-gen device is four inches smaller in terms of width and an inch smaller in depth, but five inches taller. The new model is, also, 5.5lbs lighter and has a two-inch shorter cord.

Interestingly, the new model is $20 cheaper than the original, which, given that the main features are the same, it appears to make it the better buy.

The second-gen Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer DG551 can be bought direct from Ninja’s website in the US, as well as at Amazon, Kohl’s and Best Buy. The original model is available at Belk and Walmart, so we imagine that the second-gen version will soon be available from these stores, too.

  • Value score: 5/5

Design

  • Removable grill grate and crisper basket 
  • Can fit 24 hot dogs or up to six steaks at a time 
  • Digital display lets you choose cooking function and doneness level, and utilize the thermometer 

The second-gen Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer is an indoor grill and air fryer that can also bake, roast, dehydrate, and broil. This updated model is smaller in terms of width and depth, which will be helpful if you’d like to keep it on your countertop. It is, however, 16 inches tall, which could make it tricky to fit under wall-mounted cabinets. At 16lbs., it’s average as far as indoor grills go and can be easily moved around..

When you’re ready to cook, you’ll insert the cooking pot every time as it catches grease and food debris. From there, you’ll place either the grill grate, which has handles for easy removal, or crisper basket on top of the cooking pot. The crisper basket has a capacity of four quarts, and the grill grate is large enough to fit six steaks or 24 hot dogs. Even though both the basket and the grate have handles, they’ll be too hot to pick up without oven mitts when your food is done cooking – and using a spatula or tongs to remove food isn’t as easy as you’d think, due to the deep grooves of the grill grate.

Where the Ninja Foodi 6-in-1 10-qt. XL 2-Basket Air Fryer with DualZone Technology has two baskets that allow you to cook two batches of food at different temperatures, the Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer has just a single large basket, so different foods will have to be cooked together, and at the same temperature.

The Foodi Smart Thermometer fits on the side of the appliance. It can be removed, unwound from its case, and plugged into the front of the unit. The digital display is fairly easy to use thanks to labeled buttons with options to grill, air crisp, roast, bake, broil, and dehydrate, while arrow buttons enable you to increase or decrease the temperature or cooking time. When the thermometer is plugged in, you can hit the Present Manual button and then use the arrow buttons to choose which type of protein you’re cooking (i.e. fish, steak, chicken, etc.) and your doneness levels (ranging from Rare to Well).  The Smart Cook System will monitor the internal temperature of the meat via the thermometer, and detect when the meat is finished cooking per your settings.

Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer, 2nd Generation with preset manual buttons

(Image credit: Future)

You’ll need to clean the cooking pot, and either the grill grate or crisper basket, after each use – a cleaning brush is supplied for this – and the splatter shield must also be removed and cleaned. All items are dishwasher-safe.

  • Design score: 4 / 5

Performance

Prior to testing the second-gen Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer, we’d been using the Ninja Foodi 6-in1 10-qt. XL 2-Basket Air Fryer with DualZone Technology for nearly a year. We appreciated the versatility of a Ninja unit that could air fry, roast, bake, broil, and dehydrate, so we were excited to test out a Ninja product that had an added grilling feature.

The convenience of an indoor grill cannot be overstated, especially one that doesn’t require more effort than putting in a grill grate, hitting the grill button, and waiting less than 10 minutes for it to heat up. We cooked various meats and vegetables on the grill, some of which were frozen. Although it doesn’t have the smoking capability of a charcoal or wood-burning grill, the second-gen Foodie Smart XL 6-in-1 produced the same grilling effects as a gas grill. Our meats were charred, and vegetables were seared to perfection.

When cooking meats, we used the thermometer and the Preset Manual button at times to achieve certain levels of doneness like medium-well and well done.

thermometer and the Preset Manual button on the Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer

(Image credit: Future)

Whether we were using the preset protein settings or not, we did have to pay close attention to the grill when we cooked vegetables and meat at the same time. We would have to add the vegetables later than the meat, and sometimes we had to remove them before the meat was done. This is similar to the kind of experience you might have with an outdoor grill, though with a gas grill, you could work around this by changing the intensity of different burners; unfortunately, that option is not available with this indoor grill.

Air frying veg

(Image credit: Future)

Ninja calls the air-fry feature on this appliance Air Crisp. With the Ninja Foodi 6-in1 10-qt. XL 2-Basket Air Fryer with DualZone Technology we are able to use olive oil on our meats and vegetables, but with the second-gen Ninja Foodie Smart XL 6-in-1 we could not. Ninja recommends using oils with high smoke points, such as canola, avocado, vegetable, or grapeseed oil. Olive oil can result in smoke emitting from the appliance which is a safety hazard.  So, we bought vegetable oil to coat our food before pressing the Air Crisp button.

In our experience we’ve found that this appliance works better at air frying, roasting, broiling, and dehydrating than the Ninja Foodie 6-in-1 10-qt. XL 2-Basket Air Fryer with DualZone Technology. We’re not sure if this is because the Foodie Smart XL 6-in-1can reach temperatures of up to 500 degrees (compared to the air fryer’s 450 degrees), but either way, food had a crispier texture and tastier flavor when we cooked with this unit.

On one hand, it was nice to be able to cook meat and vegetables at the same time in the 4-quart basket, like a crock pot, only much quicker. However, there were times, as mentioned, when the vegetables cooked faster than the meat, and we had to try to pull the vegetables out with a spatula or pair of tongs before they burned.

No matter which cooking setting we used on the appliance, we appreciated the fact that it notified us when to add food, turn food over, and remove it.

Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer, 2nd Generation air frying chicken and fries

(Image credit: Future)
  •  Performance score: 4 out of 5 

Ninja Foodie Smart XL 6-in-1 Indoor Grill & Air Fryer with Built-In Thermometer, 2nd Generation score card

Attribute Notes Score
Value Widely available in the US when shopping direct from Ninja or resellers. Previous version is still available in US, UK and Australia. 5/5
Design This sleek indoor grill and air fryer has a spacious grill grate and a crisper basket for cooking food, as well as a digital display that lets you choose the cooking time and temperature. 4/5
Performance The versatile cooking appliance cooks food to crispy or charred perfection in a short amount of time, even informing you when to add food and turn it over. If it could cook our vegetables and meats at the same time at different temperatures, it would score a perfect 5 out of 5. 4/5

Should I buy?

Buy it if…

Don’t buy it if…

  • First reviewed: September 2022