Model change. This page reviewed the Ninja Foodi Smart XL (DT251)until September 2026, when its Amazon listing began reporting “Currently unavailable” and no live DT251 oven listing remained. It now reviews Ninja's replacement, the Prestige Smart XL with Pro Cook System (DT551): the same single-cavity two-level XL oven with the same kind of integrated thermometer. The URL is unchanged because the oven and the buying question are the same one.
This review used to price the probe against the identical oven without one, and that comparison swung from “roughly double” to “about ten dollars” and back inside a year. It is no longer possible: the probe-less
Foodi XL Prowas discontinued in November 2026 along with the rest of SharkNinja's DT200 flat-oven line. The price-multiple reasoning has been removed from this page rather than re-pointed at a third oven, and the probe is now judged against the field.
The short answer
The DT551 is a two-level XL Ninja cavity with an integrated thermometer in it, and since November 2026 it is the only one of those Ninja sells. If you roast meat often, take it — cooking to a real internal temperature instead of guessing is the single biggest upgrade a home cook can make. If you mostly cook trays, look harder at what else the money buys: the one-level FO101 French Door Premier is a good deal cheaper, and a documented Breville-class oven is not far above. The honest reservation about this oven is the paperwork: SharkNinja publishes no rated wattage and no interior volume for it, which on our rubric is not a small thing.
What you get for the step up
One thing, and it is a real one: an integrated probe, which Ninja calls the Pro Cook System and describes as setting doneness from rare to well done at the touch of a button. Around it is the XL cavity the Foodi line used — two genuine cooking levels, a big box, ten functions on a dial that mostly changes fan speed and set point. Two levels matters more than the function count: it is the difference between cooking a tray of vegetables under a tray of chicken in one pass and doing them in two, and it is the thing no other Ninja on sale offers. The probe adds a second axis to that — you can roast the chicken to 165°F rather than to a timer that does not know how cold the meat started.
The capacity claim is stated as objects rather than a volume, as it is across the Ninja line, and for this model Ninja states it generously: two 9x9 baking trays, nine slices of toast or nine bagel halves on a rack, up to twenty cookies, a turkey up to twelve pounds, and up to eight pounds of air-fry capacity. It is a claim you can measure against your own sheet pan, which is the most you can ask of a maker that will not publish an interior volume.
What Ninja publishes, and what it does not
Less than the price suggests. For this SKU SharkNinja publishes no rated wattage and no interior volume in cubic feet or liters, which is why this oven scores poorly on documentation — and the Ninja oven that did publish a rating-plate wattage, the Foodi XL Pro, is the one that left the market. We do not print a running cost here, because there is no published watt figure to base one on and we will not borrow another model's or invent one — the by-model table lists only the ovens we could cost honestly. What Ninja does state for this model is a one-year warranty and a chassis of 20.2 by 17.1 by 13.3 inches at 33.75 pounds, which is enough to check it against your counter even though it tells you nothing about the inside.
Is the probe worth it?
It depends on whether the food you cook has an internal temperature worth measuring — but it depends on that much less than it used to. A roast, a whole chicken, a pork loin, a thick steak are all cooked correctly to a number rather than to a clock, and a probe removes the single largest source of home-roasting failure. A tray of fries does not have a meaningful internal temperature; neither does toast or a reheated slice of pizza. For two years that test came with an arithmetic shortcut — how much more than the identical probe-less oven — and that oven no longer exists, so the test is now the plainer one: a decent instant-read thermometer costs a small fraction of what this oven costs over a cheaper large Ninja, and the only thing it will not do is switch the oven off for you. If you roast weekly, the automation is worth it. If you roast at Thanksgiving, buy the thermometer. Watch the live price above either way.
The footprint problem it inherits
The DT551 is a big box — genuinely furniture-sized rather than a tidy countertop appliance. Ninja states 20.2 by 17.1 by 13.3 inches and just under thirty-four pounds. Two cooking levels take vertical room and the XL cavity takes horizontal room, so before this oven goes on your list, measure the counter, including the depth from the wall to the front edge. If space is the binding constraint rather than money, the flip-away Ninja SP line keeps the power and folds against the backsplash, and our under-cabinet picks are built around exactly this constraint.
Who should skip it
Two people. Anyone who wants a wattage they can check before buying: SharkNinja publishes nothing at all for this model, and the one Ninja oven still on sale that does publish a figure is the much smaller SP101 — so if a running cost you can verify matters more to you than a probe, you are looking outside this oven and probably outside the brand. And anyone whose counter cannot take a furniture-sized box — if you want the probe in a smaller footprint, the flip-away SP line pairs vertical storage with a thermometer in the higher trims. See where the DT551 lands against the field in our probe-thermometer roundup.
How we picked
Ovens we claim to have cooked in: 0
Everyone in this category tells you they roasted forty chickens. We have roasted none, and we say so. Here is what we do instead: read the manufacturer's manual and spec sheet, record the published wattage, interior volume, temperature range and warranty term, work out what the oven costs to run for an hour and for a year, show the arithmetic so you can redo it with your own electricity rate, and cite all of it. Where a brand publishes no wattage, we print no running cost rather than borrowing a number from a similar model. Prices come live from Amazon's API and disappear rather than go stale.
The scores above are judgments from that documented research — not test results. One of the five metrics is Documentation: whether the manufacturer will tell you what its oven draws at all. The full rubric, including what disqualifies an oven, is published in full.
