Ninja AF451UK vs AF400UK: Ultimate Dual Zone Air Fryer Comparison for 2025

Air fryers have revolutionized home cooking by offering a healthier and more efficient alternative to traditional frying. Among the top contenders, the Ninja AF451UK and AF400UK Dual Zone Air Fryers stand out for their innovative design, advanced features, and growing popularity. Choosing between these two models can be challenging – especially when both offer impressive performance and functionality.

In this comparison guide, we’ll provide a detailed overview of the Ninja AF451UK vs AF400UK, highlighting their differences in features, capacity, and smart technology. While price is a factor, this comparison focuses on what truly matters – usability, versatility, and the ability to meet the demands of busy kitchens and larger households.

Both models feature Dual Zone technology, allowing you to cook two dishes at once, and offer generous cooking capacity, making them ideal for families and entertaining. If you’re considering adding a high-performance air fryer to your kitchen, this side-by-side comparison will help you decide which model is the better fit for your needs.

Side-by-Side Comparison: Ninja AF451UK vs AF400UK Dual Zone Air Fryers

The key distinction between the Ninja AF451UK and AF400UK Dual Zone Air Fryers lies in the Smart Cook System. The AF451UK is equipped with a Smart Thermometer, a valuable addition for those who frequently cook meat.

This built-in probe allows you to monitor the internal temperature of your food in real time, ensuring precise and perfectly cooked results. In contrast, the AF400UK lacks this feature, making it slightly less efficient when it comes to achieving optimal doneness for meat-based dishes.

Similarities Between Ninja AF451UK vs AF400UK

The Ninja AF451UK and AF400UK Dual Zone Air Fryers share a wide range of similarities, making both models excellent choices for health-conscious home cooks. Below are the common features that highlight their shared strengths:

Size and Design: Both units have identical dimensions of 27 x 41 x 32 cm and feature a sleek dark charcoal grey finish. Constructed from a combination of durable aluminum and plastic, they offer a solid build while remaining lightweight and easy to move.

Cooking Functions: Each air fryer includes six versatile cooking functions – Air Fry, Max Crisp, Roast, Bake, Reheat, and Dehydrate. This broad functionality allows you to prepare everything from crispy chicken to dried fruits with minimal effort.

Special Features: Both models are equipped with innovative features such as Dual Zone Technology for cooking two foods simultaneously, the Match Cook function for syncing cooking settings across baskets, and Smart Finish, which ensures both dishes are ready at the same time.

Ease of Cleaning: Designed with convenience in mind, these air fryers come with dishwasher-safe components that are easy to remove and clean, simplifying post-cooking cleanup.

Wattage and Warranty: Both models operate at a powerful 2470 watts and include a one-year limited warranty, giving users confidence in the performance and durability of their appliance.

Ninja Foodi MAX Dual Zone Air Fryer AF451UK/AF400UK Smart Cook System

If you’re looking for an air fryer that can cook multiple dishes simultaneously while ensuring consistently great results, the Ninja Foodi Max (AF451UK) Dual Zone Air Fryer is a leading choice. This high-performance appliance is loaded with user-friendly features and has earned widespread praise from satisfied customers.

A key highlight is its dual-zone cooking system, which lets you prepare two different meals simultaneously-ideal for busy families or anyone wanting to cut down on cooking time. The Smart Cook System with an integrated Smart Thermometer takes the guesswork out of cooking, ensuring your food is perfectly cooked every time.

Ninja Foodi MAX Dual Zone Air Fryer with Smart Cook System AF451UK

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With a generous 9.5-liter capacity, this model is great for preparing meals for the whole household. It offers six versatile cooking functions-Air Fry, Max Crisp, Roast, Bake, Reheat, and Dehydrate-giving you the flexibility to make everything from crispy snacks to baked treats. The intuitive digital controls make it simple to choose the right settings and customize time and temperature.

Cleanup is hassle-free, thanks to dishwasher-safe baskets and crisper plates. Plus, the included recipe guide provides plenty of culinary inspiration to get started. Delivering 2470 watts of power, this air fryer is both efficient and effective. It also comes with a one-year limited warranty, giving you peace of mind.

All in all, the Ninja Foodi Max (AF451UK) stands out for its ease of use, smart features, and reliable performance. Whether you’re cooking for a crowd or just want to simplify your mealtime routine, this air fryer is a smart and worthwhile addition to your kitchen.

Ninja Foodi MAX Dual Zone Air Fryer with Smart Cook System AF451UK

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Pros ✅

• Dual zone cooking
• Smart finish feature
• Digital control panel
• Large 9.5-liter capacity
• Six cooking functions
• Dishwasher safe parts
• Smart thermometer included

Cons ⚠️

• Expensive
• Bulky dimensions
• Limited color options

Quick Rundown of Ninja AF400UK Dual Zone Air Fryer

Ninja Foodi MAX Dual Zone Air Fryer [AF400UK] 9.5L, 2 Drawers, 6 Functions, Black

• Temperature Control: The air fryer has 6 different temperature settings from 80 to 240 degrees Celsius for versatile cooking.
• Dual Zone: The air fryer has two separate trays, each with its own temperature control for cooking different foods simultaneously.

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Pros ✅

• Six cooking functions
• Dishwasher safe
• Two (4.75L) baskets and crisper plates
• Smart finish feature
• Cooks two foods at once
• Dark charcoal grey color
• One year limited warranty

Cons ⚠️

• No smart thermometer

Conclusion: Ninja AF451UK vs AF400UK

After thoroughly comparing the Ninja AF451UK and AF400UK Dual Zone Air Fryers, it’s evident that both appliances bring a range of impressive features to the table. They share similar dimensions, construction materials, and core cooking functions.

However, the AF451UK distinguishes itself with advanced features such as the built-in Smart Thermometer and Smart Finish technology. It also offers greater versatility with its enhanced dual-zone cooking, allowing two different meals to be prepared at once. That said, the AF451UK comes with a higher price tag and is noticeably bulkier and heavier than the AF400UK.

In the end, the right choice depends on your needs and priorities. If you value advanced tech features and the convenience of cooking multiple dishes simultaneously-and budget isn’t a concern—the Ninja AF451UK is the superior pick. On the other hand, if you’re looking for a more budget-friendly model that still delivers excellent performance, the Ninja AF400UK remains a fantastic alternative.

Ultimately, whether you choose the AF451UK or AF400UK, both models are highly rated by users and backed by a one-year limited warranty-making either a smart and reliable addition to your kitchen.