Ninja is one of the biggest air fryer names in the UK, and the 4.7L Air Fryer Pro (AF140UK) is the one it now pitches at small households. It’s squat rather than tall, it has four buttons where some rivals have a dozen, and Ninja is unusually upfront that it’s meant for one or two people. That honesty is useful, because the most common question about it is a simple one: is it big enough?
Short answer: for one person, comfortably. For two, yes, as long as you’re not expecting a whole roast dinner in one go. This review is based on the Amazon UK listing, Ninja’s published specs, an independent test by Expert Reviews, and what owners say in their reviews. We haven’t cooked in one ourselves.
At a glance
- Best for: a single person or a couple who want chips, roast veg and reheated leftovers without heating the big oven
- Top feature: a wide, shallow 4.7L drawer that gives food room to spread out, in a body only 26.5cm tall
- Watch out for: a short power cable that can’t be swapped, only four presets, and a 1kg limit on whole chickens
- Skip if: you regularly cook for three or more, or you want two foods finishing at the same time
What you actually get
It’s a single drawer with a removable crisper plate, both non-stick and both dishwasher safe. There are four functions: Air Fry, Roast, Reheat and Dehydrate. Temperature goes up to 210°C, and Expert Reviews found the Dehydrate setting runs from 40 to 90°C for up to 12 hours. Ninja says the drawer fits a 1kg chicken or up to 500g of chips, and puts the household size at up to two people.
The controls are about as simple as an air fryer gets. Press a function, nudge the temperature and time up or down, press start. There’s no manual mode beyond that, no app and no shake reminder. If you’ve used a Ninja before, there’s nothing new to learn.
The size question, in numbers
- Dimensions: 26.5cm high, 28.5cm wide, 36cm deep
- Weight: 4.8kg
- Drawer capacity: 4.7 litres
- Crisper plate: about 21.5 x 21.5cm, measured by Expert Reviews (one owner made it 22cm each way)
- Power cable: short and fixed, going by owners (Ninja doesn’t put a length on the listing)
The height is the interesting bit. Ninja’s older 3.8L model, the AF100UK, is listed at 35cm tall. The Pro is 8.5cm shorter and holds more, because the drawer is wider and shallower instead of deep. One owner who’d come from a 5.5L fryer says the Pro actually feels roomier, since most of her old one’s capacity was in depth she couldn’t use. Floor area is what matters for chips and roast potatoes, which crisp properly in a single layer and go soggy when piled up. Our guide to what air fryer capacity actually means goes into this in more detail.
In practical terms, a 26.5cm body slides under wall cupboards with room to spare, and one owner says it fits on a cupboard shelf when she wants the worktop back. She also admits it hardly ever goes away, which is probably the real test.
The 36cm depth needs thinking about with that short cable. If your sockets are at the back of the worktop, fine. If they’re up on the splashback or off to one side, measure before you buy.
How it cooks
Expert Reviews’ tests are the most useful independent data we found. About 500g of homemade chips at 200°C for 24 minutes, shaken once, came out with very crisp ends, even browning and no pale pieces. Chips are what most people want from an air fryer, so that’s the result that counts.
Frozen hash browns were crisper on top than underneath, and the reviewer suggested turning them instead of shaking. A 1.3kg chicken, over Ninja’s stated limit and flattened to fit, came out with crisp skin and moist meat but needed extra time to cook through. That 1kg limit is a real constraint, and the reviewer said it was hard to even find a bird that small in the supermarket.
Owners back up the general picture. People mention it heating up in seconds, cooking in roughly half the time of a fan oven, and one fitting four large chicken fillets in at once. When we checked in November 2026, 87% of its 969 Amazon UK ratings were five stars and only 1% were one star. Few air fryers do better than that.
What owners like
- The size for one. A single owner who’d been weighing up 3-litre models says 4.7L turned out to be right, with room for chips to spread or for two things side by side.
- Ease of use. Lots of people call it ridiculously easy, and for first-time air fryer owners that matters more than a long list of presets.
- Cleaning. The drawer and plate wipe clean easily, and one owner says even cold water and washing-up liquid does the job.
- A gentle beep. A small thing, but one owner was relieved it doesn’t shriek at her like her old fryer did when it finished.
What owners don’t like
- The power cable. One owner knocked off two stars because it’s short and fixed, so you can’t fit a longer one and end up with an extension lead on the worktop.
- Noise is a matter of opinion. Most owners call it quiet, but one says it’s much noisier than any other air fryer they’ve used. If you’re in an open-plan flat, that’s worth knowing.
- Not much guidance. One reviewer found the included recipes thin and Ninja’s online content aimed at American cooks, so they ended up using third-party recipes.
- Limited presets. Expert Reviews listed this as a downside, along with the lack of a shake reminder. Ninja’s larger 6.2L MAX PRO has six functions, including Bake.
- Not for families. The same review was clear that it’s too small for a family dinner, and the bigger sizes are the better buy if you’re feeding four.
Running costs on a cold evening
Running costs are the main reason to buy a small air fryer for winter. Expert Reviews measured 0.617kWh after an hour running at 200°C. A full-size oven has a far bigger space to heat, so for a couple of jacket potatoes or a tray of roast veg for one, the difference adds up over a season of short, dark evenings. For the full maths with UK unit rates, see how much an air fryer really costs to run.
There’s a small mismatch on power. The Amazon listing says 2,000W, while Expert Reviews gives the rating as 1,750W. Either way, it’s a normal figure for an air fryer this size, and fine on a standard UK socket.
Who it’s for, and who should look elsewhere
It suits a solo cook, a couple, or anyone buying their first air fryer who wants something that doesn’t take over a small kitchen. It’s also a good second appliance for a bigger household that wants to do the chips while the main oven handles the roast.
If you want two foods finishing at the same time, a dual-drawer model makes more sense. The Ninja Foodi Dual Zone AF300UK is wider but handles a whole meal. If you’d like to watch your food cook and store leftovers in the same dish, the Ninja CRISPi is the odd but clever alternative. And if the Ninja name is more than you want to spend, our pick of the best budget air fryers for a small UK kitchen has cheaper options, including the Tower Vortx, which does have a shake reminder.
Getting the best out of it
- Don’t fill it to the top. Expert Reviews noted there isn’t much room to shake a full drawer. Two smaller batches will beat one crammed batch for crispness.
- Set your own reminder. With no shake alert, a phone timer at the halfway point saves you pale, soft chips at the bottom.
- Turn flat things over. Hash browns, fish fillets and anything breaded will brown more evenly if you flip them, instead of shaking.
- Jacket potatoes. It’s a good size for one or two, and our guide to a proper crispy jacket potato in an air fryer works here.
- Vegan cooking. Crispy tofu, roasted chickpeas and veg all suit a wide, shallow drawer. See what you can cook in an air fryer as a vegan beginner.
Cleaning and safety
The drawer and crisper plate go in the dishwasher, though owners say a hand wash with warm soapy water is quick enough that they rarely bother. Avoid metal utensils and scourers on the non-stick coating. Our guide to cleaning an air fryer basket without scratching it covers the gentler methods.
Like most new air fryers, expect a slight smell the first few times, which our piece on why a new air fryer smells like plastic explains. Give it space at the back and sides while it’s running, keep it away from the edge of the worktop, and unplug it when you’re done. If it ever starts smoking, it’s usually fat collecting in the drawer, and here’s how to fix that. Register it with Ninja when it arrives to get the 2-year guarantee.
FAQ
Is 4.7L big enough for two people?
For most everyday meals, yes. Chips, roast veg, sausages, a couple of chicken breasts or salmon fillets all fit. A whole roast chicken is the limit, since Ninja says 1kg is the maximum, and that’s a small bird.
What’s the difference between this and the Ninja AF100UK?
The AF100UK is the older 3.8L model. The Pro holds more and is much shorter, at 26.5cm against 35cm, but it’s slightly deeper. Both have the same four functions.
Does it have a shake reminder?
No. You’ll need to remember to shake or turn food yourself, or set a timer.
Can you bake in it?
There’s no dedicated Bake button. Some people use Roast at a lower temperature for small bakes, but expect some trial and error. If baking matters to you, the larger MAX PRO has a proper Bake setting.
Is it dishwasher safe?
The drawer and crisper plate are. The main unit just needs a wipe with a damp cloth once it’s cool and unplugged.
The verdict
The Ninja Air Fryer Pro is built for one or two people, and Ninja doesn’t pretend otherwise. It’s not the cheapest, it doesn’t have the most features, and the short cable is an annoying corner to cut. But it cooks chips well, it fits under cupboards and on a shelf, and its wide drawer makes better use of 4.7 litres than taller fryers do. If you’re one or two people and you want to stop heating a full oven for a small dinner this winter, it’s an easy one to recommend. Families should look at a dual-drawer model instead.
