Ninja Speedi 12-in-1 Multi-Cooker, Air Fryer & Slow Cooker (Grey) ON500UK

If you want the convenience of an air fryer and the flexibility of a hob-style cooker, the Ninja Speedi ON500UK is designed to sit in that middle ground. On paper, it’s a 12-in-1 multi-cooker that combines steam and convection cooking, so you can push out everyday meals faster while still aiming for the right textures (think fluffy grains or al dente pasta, tender veg, and crispier mains).

That blend of functions is the main draw here. It’s not trying to replace every specialist gadget you own, but it does look aimed at households that want one appliance to cover a lot of cooking styles without constantly changing pans and methods.

The essentials

The Speedi ON500UK bundles 12 cooking functions into one unit: Speedi Meals, Steam Air Fry, Steam Bake, Steam, Grill, Air Fry, Bake/Roast, Dehydrate, Sear/Sauté, Slow Cook, Prove and Reheat. You also get a 5.7L cooking pot and a Cook & Crisp Tray to help you layer ingredients.

In practical terms, you’re buying a multi-cooker that’s built around the “steam + convection” approach. The brand’s promise is that this helps with texture: softer, fluffy or al dente results for carbs, tenderness for vegetables, and crisping for mains.

Where it shines day to day

There’s a clear everyday use case: cooking for small households and keeping meal prep relatively straightforward. The unit is positioned as able to cook up to 4 portions, with example quantities including 4 chicken breasts, 200g of rice or 225g of pasta, plus 500g of potatoes. That tells you what kind of sizing it’s designed for.

One scenario that suits this setup: if you’re making a roast-style dinner, you could add your potatoes and veg for the tender components, then use the Cook & Crisp Tray approach to help bring crispness where it matters. The idea of “all at once” is also relevant if you’re trying to avoid timing everything separately.

What you’ll notice in use, based on its function set, is that it covers both quick and slower cooking needs. You’re not just doing air-fryer-style crisping—there’s also Slow Cook, plus Prove for dough and Reheat when you’re not cooking from scratch.

Key takeaways (and the reality check)

The 12 functions are a lot of capability, but it may not be everything at maximum performance for every cooking style. Multi-cookers like this can be brilliant for routine meals, yet they can still feel limiting if you’re after very specific culinary techniques that usually require a dedicated appliance.

Also, “up to 4 portions” is useful, but it doesn’t automatically mean it’ll be ideal for bigger batch cooking every time. If you regularly cook for more than that, you may find you’re stacking or cooking in batches more often than you’d like.

Finally, this is a compact multi-cooker concept, and compactness is a trade-off. It’s meant to replace several steps and pans, but you’ll want to be comfortable with the pot size and the tray/layering approach rather than expecting the flexibility of a full hob setup.

Tech specs

• Name: Ninja Speedi 12-in-1 Multi-Cooker, Air Fryer and Slow Cooker
• Type: Multi-cooker with air fry and slow cook functions
• Capacity: 5.7L cooking pot
• Functions: 12 (Speedi Meals, Steam Air Fry, Steam Bake, Steam, Grill, Air Fry, Bake/Roast, Dehydrate, Sear/Sauté, Slow Cook, Prove & Reheat)
• Included: Ninja Speedi 12-in-1 Multi-cooker, 5.7L cooking pot, Cook & Crisp Tray, Chef-Created Recipe Guide
• Dimensions: H 35.5 x W 38.9 x D 38.9cm
• Weight: 7.4kg
• Guarantee: 2-year guarantee (UK & ME only, with registration)
• Colour: Grey
• Model: ON500UK

Who it’s for, and who should look elsewhere

It makes sense if you’re the type of buyer who wants fewer kitchen appliances covering more bases—air fry style meals, steaming, baking/roasting, and even slow cooking—without having to juggle different tools for every step.

It’s likely a better fit if your household tends to cook around 4 portions and you want quick results for day-to-day dinners, including options like reheat and prove.

It may not suit you if you’re routinely cooking very large meals, or if you’re expecting it to replace specialist gear for the most exacting versions of each cooking method. If you only use one or two functions regularly, a simpler single-purpose appliance could be easier to live with.

Care, placement and practical setup

At 7.4kg and with a compact footprint (but still a sizeable presence), it’s worth thinking about where it’ll live permanently. If your kitchen worktop space is limited, measure first and allow room for access.

Also consider the workflow: the Cook & Crisp Tray and “layer ingredients” concept are central to how this appliance is meant to operate. If you prefer cooking in a more traditional, single-layer pan approach, it might take a bit of getting used to.

Is it worth it?

The Ninja Speedi ON500UK is worth considering if you want one counter appliance that covers a lot of everyday cooking styles—steam, air fry, bake/roast, grill, sear/sauté, and slow cooking—while aiming for better texture through its steam and convection approach.

Skip it if you regularly cook for large groups, or if you’d rather have dedicated appliances for very specific cooking results. And do keep in mind the compact pot size and portion guidance: it’s designed around small household cooking, not big batch catering.

Mini FAQ

How many cooking functions does the Ninja Speedi ON500UK have?

It includes 12 functions, covering Speedi Meals, multiple steam and air fry modes, grill, bake/roast, dehydrate, sear/sauté, slow cook, prove and reheat.

What’s the cooking pot capacity?

The cooking pot is 5.7L.

Can it cook meals for four?

The guidance provided suggests it can cook up to 4 portions, with example ingredient quantities given.

What’s included in the box?

The pack includes the Ninja Speedi 12-in-1 multi-cooker, the 5.7L cooking pot, a Cook & Crisp Tray, and a chef-created recipe guide.

Does it come with a warranty?

Yes—there is a 2-year guarantee for UK and ME customers, available with registration.