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If you like grilled steaks, juicy chicken, crispy wings, burgers, and fries but do not always want to fire up an outdoor grill, the Ninja Foodi Smart XL 6-in-1 Indoor Grill and Air Fryer (FG551) is an interesting kitchen appliance to consider.
It is much more than a countertop grill. The FG551 combines grilling, air frying, roasting, baking, broiling, and dehydrating in one machine. It also comes with Ninja's Smart Cook System and a built-in Foodi Smart Thermometer, which is designed to take some of the guesswork out of cooking meat.
On paper, that sounds like a lot for one countertop appliance. But what matters more is how it performs in a real kitchen.
After looking at the specifications and digging through customer feedback, the overall picture is positive. Owners frequently praise the grill for cooking meat well, making crispy air-fried food, and being relatively straightforward to operate. At the same time, there are some legitimate drawbacks, particularly its large countertop footprint, cleaning requirements, smoke management, and reports from some owners about the thermometer or replacement parts.
So, is the Ninja Foodi Smart XL worth buying?
For the right household, I think it can be. But it is not necessarily the best choice for everyone.
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What Is the Ninja Foodi Smart XL FG551?
The Ninja Foodi Smart XL FG551 is a countertop indoor grill and air fryer designed to replace several smaller appliances.
It offers six cooking functions:
Grill
Air Crisp
Roast
Bake
Broil
Dehydrate
The grill uses Ninja's Cyclonic Grilling Technology, which combines very hot circulating air with a high-density grill grate. The maximum temperature reaches 500°F, allowing the appliance to produce the seared exterior and grill marks people normally associate with outdoor grilling.
The Smart Cook System is the feature that makes this particular Foodi model different from a basic indoor grill. The included thermometer monitors the internal temperature of food and works with preset protein settings and different levels of doneness.
The grill is also designed for family-sized cooking. Ninja says the grill grate can handle up to six steaks or 24 hot dogs, while the included 4-quart crisper basket can handle up to 2 pounds of food.
That makes the FG551 particularly interesting for families, couples who meal prep, apartment dwellers, and anyone who wants more cooking flexibility without owning several separate countertop appliances.
The 500°F Grill Is the Main Attraction
The biggest reason to buy the FG551 is simple: it can produce surprisingly good grilled food indoors.
Ninja's Cyclonic Grilling Technology circulates air at temperatures up to 500°F around the food while the grill grate itself gets extremely hot. The goal is to create a strong sear and char-grilled flavor without needing an outdoor gas or charcoal grill.
That is particularly useful for people who live in apartments or condos, have limited outdoor space, or simply do not want to deal with outdoor grilling during bad weather.
Customer feedback strongly supports this aspect of the appliance.
Best Buy's customer reviews currently show a 4.8-star rating from more than 1,000 reviews, with cooking performance and ease of use among the most frequently mentioned positives. Customers also specifically mention the thermometer as a benefit.
Some owners report excellent results with steaks, chicken, pork chops, burgers, salmon, and other proteins.
One recurring theme is convenience. Instead of standing over a pan and constantly checking the food, you can insert the thermometer, select the appropriate settings, and let the grill guide the cooking process.
That does not make the appliance completely foolproof, but it can make cooking meat considerably less stressful.
The Smart Thermometer Is Useful - With One Important Caveat
The built-in thermometer is arguably the most interesting feature of the FG551.
Instead of relying only on a timer, the Smart Cook System is designed to monitor the internal temperature of the food. You can select from four protein settings and nine doneness levels.
For something like steak, that can be much more useful than simply following a cooking time.
A steak's cooking time can vary considerably depending on its thickness, starting temperature, and the desired doneness. A timer cannot know whether the center of the steak has actually reached the temperature you want.
A temperature probe can.
This is one reason so many customers mention the thermometer positively.
However, there is an important wrinkle in the customer feedback.
Some owners have reported problems with the thermometer over time. There are also reviews from people who say the probe did not perform as expected. One customer review noted that the thermometer was unreliable but still found that the recommended temperatures and cooking times produced excellent food.
That is worth keeping in mind.
The thermometer is a valuable feature, but I would not make my entire purchasing decision around it. The FG551 is still a capable grill and air fryer even when you use conventional cooking times and temperatures.
Six Cooking Functions Give It a Lot of Flexibility
The FG551 is much easier to justify if you plan to use more than one cooking function.
Grill
This is where the machine really stands out. It can produce grilled chicken, steaks, burgers, pork chops, seafood, vegetables, and other foods with noticeable browning and grill marks.
Air Crisp
The 4-quart crisper basket lets you make foods such as fries, chicken wings, vegetables, and frozen snacks with hot circulating air.
Ninja states that the air-frying function can use up to 75% less fat than deep frying, based on its comparison with hand-cut, deep-fried French fries.
That is a manufacturer comparison rather than a guarantee for every food, but it demonstrates the intended benefit of the air-crisp function.
Roast
The roasting function is useful for vegetables, chicken, and other foods that benefit from longer, more controlled cooking.
Bake
The FG551 can also work as a small countertop baking appliance. It will not replace a full-size oven for large batches, but it can be handy for smaller portions.
Broil
Broiling provides another high-heat option for browning and finishing foods.
Dehydrate
The dehydrator function gives the appliance another job beyond everyday cooking. You can use it for foods such as fruit, vegetables, and meat-based snacks.
Having six cooking modes in one appliance is especially useful in smaller kitchens where counter and cabinet space are limited.
How Much Food Can It Cook?
Despite the "XL" name, it is important to understand what the capacity actually means.
The grill grate can accommodate up to six steaks or as many as 24 hot dogs, according to Ninja. It can also handle mains and sides together in certain cooking situations.
The 4-quart crisper basket is designed for air frying and can handle up to about 2 pounds of food.
For a couple or a small family, that is plenty for many everyday meals.
It is also considerably more practical than a tiny personal air fryer if you regularly cook several servings.
However, the machine itself is not small.
Ninja lists dimensions of approximately 15.7 inches long, 11.1 inches wide, and 16 inches high, with a weight of around 26.9 pounds.
That means you need to think about where you are going to put it.
This is not an appliance you casually move around the kitchen after every meal.
What Do Customers Like Most?
After looking through customer feedback, several themes appear repeatedly.
1. It cooks meat very well
This is probably the strongest advantage.
Customers frequently mention steaks, chicken, pork chops, burgers, bacon, salmon, and other proteins coming out juicy and well browned.
The combination of high heat and temperature monitoring is particularly appealing to people who are not confident cooking meat on a traditional grill.
2. It is easy to use
The control system is another frequently praised aspect.
Rather than manually figuring out every temperature and cooking time, you can select the appropriate cooking function and follow the prompts.
That makes the FG551 appealing to busy households.
3. It works well indoors
For apartment residents, this can be a major advantage.
You do not need a backyard, patio, propane tank, charcoal, or favorable weather.
The machine is designed with a smoke-control system that combines the splatter shield, temperature-controlled grill grate, and cool-air zone to reduce smoke.
However, "smokeless" should not be interpreted literally.
Customer reviews show that some people still experience smoke, particularly when cooking fatty foods. Best Buy lists smoke among the most frequently mentioned drawbacks.
So it is better described as smoke-reducing rather than completely smoke-free.
4. The air fryer works well
The air-crisp function gets positive feedback as well.
Customers mention crispy fries, potato wedges, wings, and other foods coming out well.
This is important because the air fryer is not merely an extra feature that you will forget about after buying the appliance. For many households, it can become one of the most frequently used functions.
5. Cleanup is manageable
The removable cooking components are dishwasher safe, which helps.
That said, "dishwasher safe" does not mean "no cleaning required."
The splatter shield and areas around the cooking chamber can still collect grease, especially when grilling fatty foods.
What Are the Biggest Complaints?
A good product review should not ignore the negative feedback.
The FG551 has some recurring complaints worth knowing before you buy.
The Appliance Is Big
The XL capacity comes with an obvious trade-off: a large physical footprint.
Several customer reviews mention the size as a drawback. Best Buy's review data lists size among the most frequently mentioned cons.
If you have a small countertop, measure the space first.
Also remember that you need enough clearance to operate the lid comfortably.
It Can Still Produce Smoke
The FG551 is designed to minimize smoke, not eliminate it under every cooking condition.
Foods with a lot of fat can still generate smoke.
One customer specifically described the grill as not completely smokeless, although they still considered the cooking results excellent.
This is an important distinction for apartment users.
If your expectation is "I can cook bacon indoors and there will never be any smoke," you may be disappointed.
Cleaning Takes Some Effort
The dishwasher-safe components make cleanup easier, but grilling naturally produces grease and splatter.
The splatter shield needs attention, and the grill area should be cleaned regularly.
The good news is that cleaning is generally considered manageable by customers. The less-good news is that you cannot simply finish cooking and forget about maintenance.
Some Owners Have Thermometer Problems
This is probably the most important technical complaint.
There are customers who have reported problems with the Smart Thermometer, including inaccurate or unreliable readings.
Interestingly, this does not mean all owners have the same experience. Other customers specifically praise the thermometer and say it makes cooking meat much easier. Best Buy lists the thermometer among the top positive features mentioned by reviewers.
In other words, reliability appears to vary.
If you buy the FG551, I would still keep a separate instant-read meat thermometer in your kitchen. It is inexpensive insurance and gives you a second way to verify the internal temperature.
What About Long-Term Durability?
This is where the review picture becomes more mixed.
There are plenty of satisfied long-term owners. Some customers say they use the appliance frequently and continue to enjoy it.
But there are also complaints involving nonstick coatings, replacement parts, and customer service.
One recent customer reported that the nonstick coating on the crisper basket deteriorated and that a replacement part felt different from the original. The same customer also complained about the splatter shield and difficulty getting customer support.
Another recent reviewer who had used the machine extensively complained about the appliance restarting its preheat cycle when the lid was opened during cooking. Despite liking the cooking results, that customer ultimately decided to replace the appliance.
These are individual experiences rather than evidence that every FG551 will develop these problems.
Still, they are useful warnings for anyone planning to use the grill heavily for several years.
Is the Ninja Foodi Smart XL Good for Families?
Yes, particularly if your family regularly eats grilled or air-fried food.
The XL grill is considerably more useful for family meals than a very small countertop grill.
You can grill several steaks or burgers at once, and the air-frying basket gives you another cooking area for fries, vegetables, or other sides.
The ability to cook mains and sides in the same appliance can also simplify weeknight meals.
For example, you could grill chicken while preparing crispy potatoes in the crisper basket.
That is one of the strongest arguments for this appliance: it can reduce the number of separate cooking tools you need.
Is It Good for Apartment Living?
This is arguably one of its best use cases.
If you live in an apartment without a suitable outdoor grilling area, the FG551 gives you access to high-temperature indoor grilling without needing a traditional outdoor grill.
It also eliminates the need to store propane tanks or bags of charcoal.
But apartment residents should still consider ventilation.
The machine reduces smoke, but it does not guarantee a completely smoke-free cooking experience. Foods that release significant amounts of fat can still create smoke.
A kitchen hood or good ventilation is still useful.
Is It Worth Buying?
The answer depends heavily on what you want from it.
If you are primarily looking for a small air fryer, there are smaller and simpler options.
If you already own a good grill, air fryer, oven, and dehydrator, the FG551 may not provide enough additional value to justify its size.
But if you want one countertop appliance that can grill, air fry, roast, bake, broil, and dehydrate, the FG551 becomes much more compelling.
The smart thermometer is also genuinely useful when it works properly, especially for people who struggle with cooking steaks, chicken, pork, or other proteins to the desired doneness.
The customer ratings reinforce that conclusion. Best Buy currently shows 4.8 out of 5 stars from 1,077 reviews, with 96% of reviewers saying they would recommend the product. Ease of use and cooking performance are the most prominent positive themes.
That does not mean the product is perfect.
It is large, cleaning requires some effort, smoke can still occur, and there are enough reports of thermometer and component problems that I would not describe it as flawless.
But the overall customer experience is strongly positive.
Final Verdict: Ninja Foodi Smart XL FG551 Review
The Ninja Foodi Smart XL 6-in-1 Indoor Grill FG551 is one of those countertop appliances that makes the most sense when you actually use several of its features.
Its strongest qualities are the high-temperature indoor grilling, useful Smart Cook System, generous cooking capacity, air-frying performance, and six cooking modes.
For someone living in an apartment, someone who grills year-round, or a family that wants a versatile countertop cooking appliance, those advantages can be significant.
The biggest compromises are its size, cleaning requirements, occasional smoke, and mixed reports surrounding the thermometer and certain replacement components.
I would not buy it simply because it has six cooking functions. I would buy it if indoor grilling and air frying are both things you expect to use regularly.
That is where the FG551 makes the most sense.
My rating: 4.5/5
Best for: Families, apartment dwellers, steak and burger lovers, meal preppers, and people who want one appliance to handle multiple cooking methods.
Pros
Excellent indoor grilling performance
500°F high-heat cooking
Smart thermometer and doneness controls
Six cooking functions
Large family-sized grill surface
Useful 4-quart air-fryer basket
Dishwasher-safe removable components
Good overall customer satisfaction
Cons
Large and heavy countertop appliance
Can still produce smoke with fatty foods
Cleaning the splatter shield takes effort
Some customers report thermometer problems
Replacement-part durability has generated complaints
Not ideal if you only need a basic air fryer
Bottom Line
The Ninja Foodi Smart XL FG551 is not the smallest or simplest countertop cooker, but that is also not what it is trying to be.
It is designed to bring a surprisingly broad range of cooking options into one appliance, with indoor grilling as its biggest selling point.
The customer feedback suggests that the majority of owners are happy with the cooking results, especially when it comes to meat, air-fried foods, and everyday convenience.
If you have the counter space and will actually use the grill, air fryer, and other functions, the FG551 remains a versatile choice worth considering.
