The Ninja Foodi 10-in-1 Smart XL Air Fry Oven (model DT251) is a large 1800-watt countertop convection oven that air fries, roasts, bakes, and dehydrates on two levels at once, with a built-in Foodi Smart Thermometer that tells you when meat reaches your chosen doneness. It is a strong pick for families who want to replace a toaster oven and a basket air fryer with one appliance, as long as you have the counter space for a unit about 20 inches wide and can live with a noticeable fan. This research-based review covers its specs, all 10 functions, the thermometer, how it compares with Ninja’s DT201 and newer Prestige models, and the ownership details listings tend to skip.
- Ninja Foodi 10-in-1 Smart XL Air Fry Oven at a Glance
- The 10 Functions and When to Use Each
- Ninja Foodi Smart XL Air Fry Oven: How the Smart Thermometer Works
- Ninja Foodi 10 in 1 Review: Strengths and Weak Spots
- Will It Fit? A Worked Counter-Space Check
- Ninja DT251 vs DT201 vs Newer Ninja Models
- Cleaning and Long-Term Ownership
- Tips to Get Better Results
- Who Should Buy It, and Who Should Skip It
- How We Compared
- What to Look For in a Large Countertop Air Fry Oven
- Which One Should You Buy?
- Common Mistakes When Buying a Countertop Oven
- Frequently Asked Questions
Key takeaways

Ninja Foodi XL Pro Air Fry Oven, 10-in-1, Stainless Steel, DT201 | Fits 5 lb chicken, Air fry, roast, bake, broil, toast, dehydrate, reheat, pizza, 1800W
Included for 'Ninja Foodi 10-in-1 Smart XL Air Fry Oven Review' as a representative gaming product in this roundup; selection reflects the product set returned for this topic.
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Ninja Prestige Smart XL Countertop Oven, 10-in-1, Stainless Steel, DT501 | Bakes 20 cookies, Fits 12 lb turkey, Air fry, bake, toast, pizza, reheat, 1800W
Included for 'Ninja Foodi 10-in-1 Smart XL Air Fry Oven Review' as a representative gaming product in this roundup; selection reflects the product set returned for this topic.
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Ninja Digital Air Fry Countertop Oven, 8-in-1, XL, Silver, SP101 | Air fry, air roast, broil, bake, toast, bagel, dehydrate, keep warm, 1800W, Flip up & away
Included for 'Ninja Foodi 10-in-1 Smart XL Air Fry Oven Review' as a representative gaming product in this roundup; selection reflects the product set returned for this topic.
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Ninja French Door Premier Air Fry Oven, 10-in-1, 20.3 Qt, Stainless, FO101 | 450F cyclonic air, PFAS-free surface, Air fry, sear crisp, bake, broil, toast, dehydrate
Included for 'Ninja Foodi 10-in-1 Smart XL Air Fry Oven Review' as a representative gaming product in this roundup; selection reflects the product set returned for this topic.
View on Amazon- Ninja rates it to fit a 5-lb chicken plus a sheet pan of vegetables, two 12-inch pizzas, or a 12-lb turkey.
- The built-in Smart Thermometer offers 4 protein settings and 9 doneness levels, the main upgrade over the non-smart DT201.
- True Surround Convection cooks on two racks without rotating pans, and Ninja quotes a 90-second preheat.
- It measures about 17.1 x 20.2 x 13.3 inches, so measure your counter and cabinet clearance first.
- The DT251 is now mostly found as remaining or renewed stock; the Prestige Smart XL Pro (DT551) is Ninja’s newer smart-thermometer option.
Ninja Foodi 10-in-1 Smart XL Air Fry Oven at a Glance
Here are the core specifications, taken from Ninja’s owner’s manual and retailer spec listings.
| Spec | DT251 detail |
|---|---|
| Functions | 10: Air Fry, Air Roast, Bake, Whole Roast, Broil, Toast, Bagel, Dehydrate, Reheat, Pizza |
| Power | 1800 W, 120 V, 60 Hz |
| Maximum temperature | Up to 450°F |
| Convection | True Surround Convection, two-level cooking without rotating |
| Capacity examples (Ninja) | 5-lb chicken plus sheet pan of vegetables; two 12-inch pizzas; 12-lb turkey |
| Thermometer | Built-in Foodi Smart Thermometer, 4 protein settings, 9 doneness levels |
| Preheat (Ninja claim) | About 90 seconds |
| Dimensions | About 17.09 in L x 20.22 in W x 13.34 in H |
| Accessories | 2 sheet pans, 2 wire racks, air fry basket, roast tray, crumb tray, thermometer, recipe guide |
| Controls | Digital display handle that shows recommended rack positions |
Ninja also claims up to 30 percent faster cooking than a traditional convection oven and up to 75 percent less fat when air frying compared with deep frying. Read those as manufacturer figures; actual results depend on food, load size, and rack position.
The 10 Functions and When to Use Each
| Function | What it is for | Practical tip |
|---|---|---|
| Air Fry | Fries, wings, breaded foods | Use the air fry basket and spread food in one layer for crisp edges |
| Air Roast | Vegetables, chicken pieces, sheet-pan dinners | Two racks at once is where this oven shines |
| Bake | Cookies, casseroles, cakes | Convection browns faster; check early the first few times |
| Whole Roast | Whole chicken or turkey | Pair with the Smart Thermometer for doneness |
| Broil | Melting cheese, browning tops | Watch closely; top elements brown quickly |
| Toast | Bread slices | Uses slice-count settings rather than time |
| Bagel | Bagels and English muffins | Place cut sides up for even browning |
| Dehydrate | Fruit chips, jerky, herbs | Low and slow; use racks and basket for more surface area |
| Reheat | Leftover pizza, fries, roasted vegetables | Revives crispness better than a microwave |
| Pizza | Fresh or frozen pizza | Two 12-inch pizzas fit on two levels |
Ninja Foodi Smart XL Air Fry Oven: How the Smart Thermometer Works
The thermometer is what puts “Smart” in the name. It plugs into the oven and monitors internal temperature, so the oven can stop cooking when the food reaches your target. Here is the typical flow, based on the owner’s manual:
- Choose a function such as Whole Roast or Air Roast. The thermometer works with roasting and similar modes where a protein cooks for a while.
- Insert the probe into the thickest part of the meat. Avoid touching bone or fat pockets; both give false readings.
- Plug the thermometer into its jack on the oven. The display switches to show thermometer mode.
- Select the protein and doneness. Pick one of 4 protein settings and a doneness from rare to well done, across 9 levels.
- Start cooking and watch the target vs current readout. The display shows both values, so you can see progress without opening the door.
- Let the meat rest. Internal temperature keeps rising a few degrees after cooking, which is why doneness presets account for resting.
For food safety guidance, follow recognized minimum internal temperatures, such as 165°F for poultry, and use the thermometer to confirm rather than guess.
Ninja Foodi 10 in 1 Review: Strengths and Weak Spots
What it does well
- Two-level cooking without rotation. Owners and reviewers consistently highlight sheet-pan dinners on both racks as the standout use.
- Built-in thermometer. Removes guesswork for roasts, chicken, and pork, which is the most common reason people choose the DT251 over the DT201.
- Fast preheat. A 90-second preheat (per Ninja) makes it practical for weeknight meals instead of heating a full oven.
- Large capacity. Fits family-size portions, a 12-inch pizza per level, and a whole turkey on the Whole Roast setting.
- Helpful display handle. The handle shows rack positions and pauses settings changes while the door is open.
Where it falls short
- Footprint. At roughly 20 inches wide and 17 inches deep, it occupies more counter than most basket air fryers or toaster ovens.
- Fan noise. Some buyers comment on the noise level of the convection fan, which runs hard in air fry modes.
- Exterior heat. Like most countertop ovens at 450°F, the top and sides get hot; allow clearance and avoid placing items on top.
- Availability. As a 2020-era model, new stock is limited and much of what remains is renewed; newer Ninja ovens may be easier to find.
Will It Fit? A Worked Counter-Space Check
Measure before buying. The oven’s body is about 20.2 inches wide, 17.1 inches deep, and 13.3 inches tall.
- Footprint: 20.2 x 17.1 inches is about 345 square inches, or roughly 2.4 square feet of counter.
- Depth: Standard counters are about 25 inches deep, so the oven fits with around 8 inches to spare front to back, enough for the door to open forward without hanging over the edge too much.
- Height: Upper cabinets usually sit about 18 inches above the counter. With a 13.3-inch oven, that leaves under 5 inches above it. Check the clearance Ninja specifies in the manual for your unit; if in doubt, pull the oven forward from under the cabinets while cooking, because hot air vents upward.
- Door swing: The door opens down and forward; allow space in front for sliding out the sheet pans.
Example: a 30-inch stretch of counter between a sink and a fridge fits the oven with about 5 inches of side space on each side, which is workable for a dedicated appliance spot.
Ninja DT251 vs DT201 vs Newer Ninja Models
| Model | Type | Thermometer | Key note |
|---|---|---|---|
| Ninja Foodi 10-in-1 Smart XL Air Fry Oven (DT251) | 10-in-1 XL countertop oven | Built-in Foodi Smart Thermometer | Two-level cooking, 12-lb turkey capacity |
| Ninja Foodi XL Pro Air Fry Oven (DT201) | 10-in-1 XL countertop oven | No | Same core idea without the thermometer; fits a 5-lb chicken |
| Ninja Prestige Smart XL Countertop Oven (DT501) | 10-in-1 XL countertop oven | Check listing | Newer design; Ninja lists 20 cookies and a 12-lb turkey |
| Ninja Prestige Smart XL Pro Cook System (DT551) | 10-in-1 XL countertop oven | Smart Cook thermometer | Newer smart-thermometer successor in the XL range |
| Ninja French Door Premier Air Fry Oven (FO101) | 10-in-1 French-door oven | No | French doors, 450°F cyclonic air, PFAS-free surface per Ninja |
If you can find a DT251 in good condition, it covers almost everything the newer XL models do. If not, the DT551 is the closest current match for a thermometer-equipped XL oven, and the DT201 is the simpler choice if you already own a separate meat thermometer.
Cleaning and Long-Term Ownership
Countertop ovens stay pleasant to use only with regular cleaning. Ownership realities to plan for:
- Empty the crumb tray after most uses. Built-up crumbs smoke at high temperatures and can scorch.
- Line the bottom pan for messy roasts. Use the roast tray over a sheet pan so drippings stay contained.
- Hand wash accessories gently. Nonstick-coated pans and the air fry basket last longer without abrasive scrubbers. Follow Ninja’s manual on what is dishwasher safe.
- Wipe the door glass while warm (not hot). Grease is easier to remove before it bakes on during the next cook.
- Keep vents clear. Do not block the top or back with containers or a cutting board.
- What wears first: on most air fry ovens, the coating on sheet pans and baskets shows wear before the oven itself. Ninja sells replacement accessories for many models; check availability for the DT251 specifically.
Tips to Get Better Results
- Follow the display handle’s rack guidance. It reflects how the convection airflow is designed for each function.
- Do not overcrowd the air fry basket. Air needs to reach every side to crisp food.
- Toss or flip halfway for small items. Even with surround convection, fries and wings brown more evenly when moved once.
- Use a light oil spray, not pooled oil. A thin coat crisps; excess oil drips and smokes.
- Reduce oven-recipe times when adapting. Convection cooks faster; check 5 to 10 minutes early on traditional recipes.
Who Should Buy It, and Who Should Skip It
Buy it if you cook for three to six people, want sheet-pan meals on two racks, like the idea of a built-in thermometer, and have about 2.5 square feet of free counter.
Skip it if you cook mostly for one or two people (a smaller basket air fryer or compact toaster oven is quicker to clean), your counter is shallow or crowded, or you are sensitive to fan noise.
How We Compared
This is a research-based review. We did not personally use the DT251. We compiled specifications from Ninja’s owner’s manual and retailer spec sheets, compared it with Ninja’s current XL and French-door ovens, and summarized recurring owner feedback, such as fan noise and capacity praise, from public retailer listings and owner discussions.
What to Look For in a Large Countertop Air Fry Oven
Large air fry ovens look alike on a box, so a few checks separate a good fit from a frustrating one.
Electrical Load
The DT251 is rated at 1800 watts. At a standard 120 volts, that is 15 amps (1800 divided by 120), which is the full rating of a 15-amp circuit. The US electrical code calls for 20-amp small-appliance circuits serving kitchen countertops, so an outlet there usually has headroom, but running a kettle, toaster, or microwave on the same circuit while the oven is heating can trip the breaker. Spread high-wattage appliances across different outlets when possible.
Capacity Versus Counter Space
Rack count matters more than a headline capacity number. Two racks let you cook a main and a side together, but food on both racks must be spaced for airflow. If your regular meals are single-pan dinners, a second rack is a bonus rather than a necessity.
Probe Versus No Probe
Spec comparisons agree the main difference between the DT251 and the DT201 is the built-in thermometer: the DT251 includes one and the DT201 does not. If you roast chicken, pork, or steak often, the probe saves guesswork. If you mainly air fry vegetables and reheat leftovers, it adds little.
Fan Noise and Venting
Convection ovens run a fan at high speed. Leave clearance behind and above the unit as the manual directs, and avoid placing it directly under wall cabinets that can be damaged by rising steam and heat.
Which One Should You Buy?
| If you… | Choose… |
|---|---|
| Roast meat several times a week and want doneness alerts | Ninja DT251 |
| Cook mostly frozen foods, fries, and reheated leftovers | Ninja DT201 |
| Want the same functions and capacity without a built-in probe | Ninja DT201 |
| Like cooking to a target internal temperature instead of a timer | Ninja DT251 |
| Are replacing both a toaster oven and a basket air fryer | Either; both list the same ten functions and 1800 watts |
Specification comparisons describe the DT251 and DT201 as sharing the same list of cooking functions, a 450 degree Fahrenheit upper limit, and the same wattage. Some sites list different capacities or control types between them, but sources conflict, so confirm against the manual of the exact unit.
Common Mistakes When Buying a Countertop Oven
- Measuring only width. Height with the door open and clearance behind the unit decide whether it really fits.
- Overloading the racks. Piling food blocks air circulation and leaves pale, soft results.
- Buying features you will not use. A probe is helpful for roasts but redundant for snacks and sides.
- Ignoring the circuit. An 1800-watt oven sharing an outlet strip with other appliances is a common cause of tripped breakers.
- Skipping the cleaning plan. Grease buildup on the heating elements can smoke. Wipe the interior and empty the crumb tray regularly.
Frequently Asked Questions
What is the difference between the Ninja DT251 and DT201?
Both are 10-in-1 XL air fry ovens with two-level cooking. The DT251 adds the built-in Foodi Smart Thermometer with protein and doneness presets. The DT201 skips the thermometer.
Can the Ninja Foodi Smart XL Air Fry Oven cook a whole turkey?
Ninja states it fits up to a 12-lb turkey using the Whole Roast function. Larger birds will not fit, and you should confirm doneness with the thermometer.
How hot does the Ninja DT251 get?
It reaches up to 450°F. The exterior also gets hot during use, so keep clearance around it and do not store items on top.
Is the Ninja Foodi 10-in-1 Smart XL Air Fry Oven loud?
Some owners describe the fan as noticeably loud, particularly in air fry mode. It is typical of powerful convection ovens, but worth considering for open-plan kitchens.
Can I use both racks at the same time?
Yes. True Surround Convection is designed for two-level cooking without rotating pans, such as a protein on one rack and vegetables on the other.
Is the Ninja DT251 still sold?
New units are increasingly scarce, and many listings are renewed. Ninja’s Prestige Smart XL Pro (DT551) is a newer XL oven with a smart thermometer, and the DT201 remains a non-thermometer alternative.
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