Indoor grilling has moved past the era of slanted plastic plates that steam meat rather than sear it. In my kitchen, the debate has recently centered on two heavyweights: the Ninja DG551 Foodi Smart XL and the Ninja IG651 Foodi Smart XL Pro. While both carry the “Foodi” name and the promise of smoke-free indoor BBQ, they represent two different eras of Ninja’s engineering logic.
The DG551 is the refined, second-generation “box-style” grill that perfected the air-fryer-meets-grill hybrid. On the other hand, the IG651 Pro is a total architectural departure – a flat-profile “Pro” station that introduces a powered griddle and a hood-up cooking capability. After a month of searing ribeyes and flipping pancakes on both, I’ve realized that the “best” model depends on whether you view a grill as an oven replacement or a standalone flat-top station.
The Key Difference: Ninja DG551 vs. IG651 Foodi Smart Grill
The mechanical soul of these two units differs in how they apply heat to the protein.
- The Ninja DG551 (Cyclonic Focus): This unit relies heavily on 500°F cyclonic air. While the grill grate gets hot, the magic happens because the heat surrounds the food. It is essentially a high-powered air fryer with a heavy-duty grate at the bottom. It excels at thick cuts of meat where you want a “roast-like” interior with grill marks on the outside.
- The Ninja IG651 (Direct Power Focus): This model features an independently powered grill grate. Unlike the DG551, where the air heats the grate, the IG651 has a heating element in direct contact with the grate itself. This results in edge-to-edge searing and allows for “Hood Up” cooking – meaning you can use it like an outdoor BBQ or a diner-style griddle without trapped air.
Technical Comparison Table: Ninja DG551 vs. IG651 Foodi Smart Grill
| Feature | Ninja DG551 (Smart XL) | Ninja IG651 (Smart XL Pro) |
| Cooking Functions | 6-in-1 (Grill, Air Crisp, Roast, Bake, Broil, Dehydrate) | 7-in-1 (Grill, BBQ Griddle, Air Crisp, Roast, Bake, Broil, Dehydrate) |
| Heating Tech | 500°F Cyclonic Air | 500°F Powered Grate + Cyclonic Air |
| Griddle Included | No | Yes (12” Flat Top BBQ Griddle) |
| Cooking Style | Hood Closed Only | Hood Up or Hood Down |
| Thermometer | Foodi Smart Thermometer | Foodi Smart Thermometer |
| Footprint | Vertical/Tall (16″ Height) | Wide/Low (7″ Height) |
| Capacity | Fits 6 Steaks | Fits 6 Steaks / 6 Pancakes |
| Material | Ceramic Coated | Ceramic Coated |
| Buy On Amazon | Buy on Amazon | Buy on Amazon |
Detailed Comparative Review: My Personal Test Kitchen
Design: Countertop Verticality vs. Horizontal Workspace
When I first placed the DG551 on my counter, I appreciated its compact footprint. It’s a tall machine (16 inches), which means it takes up less width but demands more “headroom.” If you have low-hanging cabinets, opening the lid can be a bit of a squeeze. The black and silver finish is classic Ninja – utilitarian and rugged.
The IG651 Pro feels entirely different. It is low-profile and wide. At only 7 inches tall when closed, it looks like a professional flat-top griddle. However, it is much wider (over 17 inches). I found that the IG651 felt more “open” and less like I was reaching into a deep bucket to flip my food. The Pro model feels more like a piece of culinary equipment, while the DG551 feels like a versatile kitchen appliance.
- NINJA FOODI SMART XL GRILL: Updated, sleek design with the same functions & benefits. Indoor countertop Grill and Air Fryer with the...
- SMART COOK SYSTEM & THERMOMETER: The Foodi Smart Thermometer enables you to achieve the perfect doneness, from rare to well-done with 4...
- FLEXDOOR: Creates two separate ovens. Access just the top for quick meals and snacks, or open the full door so you can cook 2 meals, 2...
- FLAVORSEAL TECHNOLOGY: Two separate ovens prevents smells from crossing between ovens, so your flavors stay separate.
Ease of Use: The Smart Thermometer Advantage
Both units include the Foodi Smart Thermometer, which I have come to rely on religiously. I tested two New York Strips – one in each machine – set to “Medium Rare” (Level 3). The interface on both is identical: you select your protein type, set the doneness level, and the machine beeps when it’s time to flip and again when it’s time to rest the meat.
The DG551 was slightly faster at reaching the target temperature because the smaller, enclosed “box” cavity retains heat with incredible efficiency. However, the IG651 was easier to use for “visual cooking.” Because I could keep the hood up, I could watch the sear develop on a piece of salmon without interrupting the heat cycle by opening a lid.
Functions: The Griddle Game-Changer
The DG551 is a master of the “Air Crisp” and “Grill” duo. My frozen fries came out at 75% less fat than deep frying, and they were indistinguishable from restaurant quality. It’s a 6-in-1 workhorse that handles roasting a whole chicken just as well as grilling a burger.
However, the IG651 introduces the BBQ Griddle. This isn’t just a flat plate; it’s an interlocking system that harnesses the direct heat of the powered grate. I used it for a “Diner Breakfast” – pancakes, eggs, and bacon all on one surface. You simply cannot do this in the DG551. If you enjoy making fajitas, smash burgers, or cheesesteaks, the IG651 is in a different league. The “Hood Up” feature effectively turns your kitchen counter into a professional flat-top station.
Maintenance: The Cleanup Reality
Ninja claims both are “easy to clean,” and for the most part, they are. The ceramic coating is truly non-stick.
- DG551: The deep cooking pot and crisper basket are easy to toss into the dishwasher. However, the splatter shield on the top lid (which prevents smoke) gets very greasy very quickly. I recommend cleaning it after every use to prevent the unit from smoking in future sessions.
- IG651: The griddle and grate are flat and take up less room in the dishwasher than the DG551’s deep pot. The smoke control system on the IG651 seemed slightly more robust during my “high-fat burger” test, likely due to the improved airflow in the wider chassis.
Ninja DG551 (Smart XL) Foodi Grill
- NINJA FOODI SMART XL GRILL: Updated, sleek design with the same functions & benefits. Indoor countertop Grill and Air Fryer with the...
- SMART COOK SYSTEM & THERMOMETER: The Foodi Smart Thermometer enables you to achieve the perfect doneness, from rare to well-done with 4...
Pros:
- Compact Width: Perfect for kitchens with limited counter space.
- Deep Pot: Excellent for roasting smaller whole chickens or deep-dish baking.
- Cyclonic Efficiency: Cooks frozen foods to char-grilled perfection in under 25 minutes.
- Intuitive UI: Very easy for beginners to navigate the smart doneness levels.
Cons:
- Hood-Closed Only: You lose the sensory experience of “real” grilling.
- No Griddle: You’re limited to grate-style cooking only.
- Height: Might not open fully under all cabinets.
Ninja IG651 (Smart XL Pro) Foodi Grill
- FLEXDOOR: Creates two separate ovens. Access just the top for quick meals and snacks, or open the full door so you can cook 2 meals, 2...
- FLAVORSEAL TECHNOLOGY: Two separate ovens prevents smells from crossing between ovens, so your flavors stay separate.
Pros:
- Powered Grate: Direct heating element provides a superior, edge-to-edge sear.
- 7-in-1 Versatility: The BBQ Griddle makes this a 24-hour appliance (pancakes to steaks).
- Hood-Up Cooking: Best for delicate foods like eggs or thin vegetables.
- Low Profile: Fits under almost any cabinet setup.
Cons:
- Width: Takes up a significant amount of horizontal counter space.
- No Deep Pot: Less effective for “tall” roasts compared to the DG551.
- Price: Generally sits at a higher price point due to the Pro features.
The Verdict: Which Ninja Rules the Counter?
After weeks of side-by-side testing, the choice boils down to Utility vs. Versatility.
I recommend the Ninja DG551 if:
You want an “All-In-One” replacement for your air fryer and outdoor grill. If your primary goal is to cook proteins to perfect doneness using the smart thermometer and air-fry sides like wings and fries, the DG551 is a perfect, space-saving choice. It’s a vertical powerhouse that masters the basics with flawless execution.
I recommend the Ninja IG651 Pro if:
You are a “Griddle Enthusiast” who wants professional-grade searing. If you want the ability to make smash burgers, pancakes, and seared fish with the hood up – essentially having a diner flat-top in your kitchen – the IG651 is worth every penny. The independently powered grate is a massive technical leap over the cyclonic air system of the DG551.
My Personal Take: I prefer the Ninja IG651. The ability to use the flat-top griddle has doubled the amount of time I actually use the machine. While the DG551 is a great grill, the IG651 is a complete outdoor kitchen scaled down for your countertop.
Frequently Asked Questions
Does the IG651 smoke more because of the hood-up feature?
Actually, no. Ninja’s smoke control system (the splatter shield and cool-air zone) works quite well. When the hood is up, you are using direct bottom heat, similar to a stovetop pan. As long as you aren’t using oils with low smoke points (like butter or extra virgin olive oil) at 500°F, the smoke is very manageable.
Can I air fry in the IG651?
Yes! Even though it looks like a griddle, it has a “Hood Down” cyclonic air mode. It comes with a 4-qt crisper basket that fits inside, allowing it to function exactly like the DG551 for air frying.
Which model is better for a family of four?
Both are “XL” models. They both fit about 6 steaks or 24 hot dogs. However, the IG651 feels larger because the flat griddle allows you to crowd more small items (like shrimp or chopped veggies) than the grill grate of the DG551.
Do I need to preheat these machines?
Yes, and both machines insist on it. The preheat cycle for the IG651 is slightly longer because it is heating a heavy, powered grate, but the result is a much better sear than if you skipped the wait.
Is the ceramic coating safe?
Yes, both units are PTFE/PFOA-free. The ceramic coating is highly durable and, in my experience, holds up better over time than traditional chemical non-stick surfaces, provided you don’t use metal utensils.