Many people are waking up to the fact that the air quality in our homes can be very poor. This not only opens up to extreme symptoms during allergy season, but also to ill-effects from excess dust and pollution that enters our space. Having an air purifier in the home can therefore make a massive difference.
Research has shown that the air we breathe every day is often worse than that outdoors on all but the most polluted streets. Particles from traffic fumes, pollen and more are pulled in as we enter the front door or open a window and there often isn’t enough ventilation to remove them.
The chemicals in cleaning products, fresh paint, new furniture, cooking fumes, dust and other nasties only add to the problem.
You may think regular cleaning and vacuuming keeps the problem of bad air at bay, but this alone can’t deal with anything smaller than dust particles. A dedicated air purifier will thoroughly clean the air and, if you pick a good one that’s the right size for the room, you’ll really notice the difference.
Read on to find out how to choose the best air purifier for your space.
Read next: Looking to defeat the damp? Take a look at our roundup of the best dehumidifiers
The best rated air purifiers 2021
1. Blueair Blue 3210
Best home air purifier overall
Room size: 17m2
Noise: from 18dB
Dimensions: H42.5cm x W20cm
Reasons to buy: Lovely, small design; Interchangeable coloured pre-filter sleeves; Quiet
Reasons to avoid: No app; only 3 speeds
Blueair has become a true leader in the air purifier space, and the Blue 3210 has a lot of the same great features but with a serious upgrade in terms of style. Simpler than other high-tech air purifiers with a ‘plug and go’ system, it’s also whisper-quiet and whirs into action as soon as unwanted particles enter the space.
Without an app, you can control the purifier with a single touch control on the top of the device. Modes include Auto (which we used the most), Night, Everyday and Boost. The Night mode turns the fan speed down to its lowest setting, but in our experience it is quiet enough on Auto to sleep through.
The Blueair Blue 3210 comes with a choice of sleeves that serve the dual purpose of pre-filter and a way to fit your device to your personal style. The colours include dark grey, light grey, pink, green and blue. We tested with the pink (Archipelago Sand) and green (Aurora Light) variations, and they look as lovely in real life as they do in images.
2. Levoit Core 300 Air Purifier
Room size: 40m2
Noise: from 24dB
Dimensions: H35.8 x W21.8cm
Reasons to buy: Very quiet on lowest settings, eco-friendly, sleep mode
Reasons to avoid: Only 3 speeds
An affordable but high-performing option, the Levoit Core 300 is a low-maintenance device that is capable of cleaning a room up to 40m2. The HEPA H13 filter does a brilliant job of clearing 99.97% of pollutants from the air, from dust to smells and pet hair, and it does it without making a huge amount of noise.
It’s true that the Dimplex DXAPV3N listed below is even cheaper than the Levoit offering, it can still be considered a budget option for those who just want something that will clear their living area or kitchen. It’s easy to use, too, with user-friendly controls on the top of the machine and a simple design that makes checking the filter (and replacing it) a doddle.
We also really like how the Levoit Core 300 looks, combining the white cylinder design that’s common in the air purifier world with a more design-friendly minimalism. The size also makes it easy to tuck away in a corner or under a desk if you don’t want it to be a focal point.
Ideal Home rating: 4 out of 5 stars
3. Dyson Pure Cool Me
Best purifying fan
Dimensions: 40.1 cm (H) x 24.5 cm (W) x 24.5 cm (D)
Noise levels: 44-61dB
Reasons to buy: Dyson’s engineering ensures clean, filtered air
Reasons to avoid: It’s louder than other purifiers, so not ideal for workspaces
Dyson doesn’t pitch the Pure Cool Me as an air purifier that cleans all the air in a room, so it doesn’t give figures for recommended room size, air changes per hour or CADR. Instead it is billed as a fan that cleans the air in the personal space around you. The idea is that it sits on your desk or bedside table and directs filtered air straight at you: your personal clean air bubble.
The industrial design is similar to Dyson’s larger Air Multiplier fans, but they don’t filter all the air: air that passes through the machine’s fan is filtered but then the clever design multiplies that air by pulling more (unfiltered) air along with it.
The design is cute. It measures 401 x 254 x 274mm. You choose the angle of airflow up and down manually with your hand but there’s a small remote control for everything else. This attaches magnetically to the front when not in use. You’re a bit lost without it: only able to turn the fan on and off.
With the remote you can choose fan level (0-10), oscillation (off or 70 degrees), sleep timer (30 mins to 8 hours) and see how much life the filter has left. There is a filter change alert and its life is given as a year if used 12 hours a day.
It uses an activated carbon and glass HEPA filter and noise is 44-61dB. Unsurprisingly, it sounds like a fan.
We tested the Dyson just like the others, to see what impact it had on air quality in an average-sized bedroom. The results weren’t terrible: it removed 67 per cent of PM2.5 and 79 per cent of PM10 particles in an hour. This means that despite not setting out to purify the air in the whole room, it does a better job of it than some.
The focussed beam of air is pleasant and cooling in the summer. So if you’re in the market for a fan anyway, and your budget stretches to the Dyson, it’s a good buy. It would be lovely on a bedside table or desk in the summer. But if your priority is air purification then you can get something better for much less.
Ideal Home rating: 4 out of 5 stars
4. Dimplex DXAPV3N
Best budget air purifier
Dimensions: 13.3 cm (H) x 24.8 cm (L) x 33.3 cm (W)
Noise levels: 40-50dB
Reasons to buy: It’s on a discount right now, so great if you’re on a budget
Reasons to avoid: It’s not that suitable to larger rooms
If you’re on a really tight budget, this slim air purifier is better than no air purifier at all. It’s the size of a cookbook stood upright (333 x 248 x 133mm) so doesn’t take up much space on a bedside table. The control is simply a lever on the right-hand side that chooses between the two speeds and off.
Noise levels are 40-50dB. On both settings it sounds like a fan but it’s a white noise you could easily ignore and go to sleep with. Filter life is quoted as 2,000 hours of use but there’s no filter change indicator.
Filtration is HEPA and carbon but the size of the filter is small compared with others on test, so it’s surprising that it claims to be suitable for a room measuring up to 28m². The technical data reveals that this is based on 1.75 air changes per hour. So if you want 5 air changes per hour, your room would have to be just under 10m², which sounds more realistic. CADRs for smoke, pollen and dust are 80, 89 and 79m³/h, much lower than others on test.
These were borne out by the test results. It removed 57 per cent of PM2.5 and 66 per cent of PM10 particles in an hour. This makes it the least effective air purifier on test but it’s also by far the cheapest. If you have a small bedroom then using the Dimplex would improve air quality. But we’d recommend the Blueair 411 as well worth the extra expense.
Ideal Home rating: 4 out of 5 stars
5. TaoTronics TT-AP005
Dimensions: 22.5 x 22.5 x 38cm
Noise level: from 25dB
Reasons to buy: lightweight and small enough for most spaces; 12-hour timer; quiet on lowest settings
Reasons to avoid: won’t do much good in larger spaces; no smart features
A 3-stage filtering system including HEPA and carbon and a simple design with light indicator make the TaoTronics TT-AP005 air purifier a fantastic option for anyone who is enamoured with some of the ‘fancier’ features of more expensive models but who doesn’t want to spend the earth. The purifier will suit anyone wanting cleaner air in a space up to 323 sq ft.
Like products from Dyson and Blueair, the TT-AP005 has a light on top that indicates air quality – blue for excellent, green for good, orange for moderate and red for poor – that helps you manage its performance. There’s no app or smart home compatibility, but you can set a timer for 2, 4, 8 and 12 hours or place it in sleep mode to reduce noise to 24dB.
The fan can also be adjusted between three speed settings, or you can put it in auto mode to let the purifier manage itself based on air quality.
How to choose the best air purifier
Do air purifiers work?
Yes. Read the reviews because some are better than others and you should pick the right machine for your room size. But yes, they remove everything from dust to very fine particles from the air, quietly and invisibly.
In the summer, opening doors and windows for ventilation is a great way to improve indoor air quality – unless you live on a really congested road. But in colder months an air purifier is just the ticket.
Are air purifiers effective?
Improving indoor air quality is beneficial for anyone. Given a choice between walking down a polluted main road or a side road next to a park, you’d pick the latter every time. Indoor air quality is under threat from wafted-in pollutants, allergens, dust particles, candles, open fires, Volatile Organic Compounds (VOCs) from cleaning products and “off-gassing”.
This is a process where VOCs are released from paints and plastics for years. So using an air purifier is like taking the leafy side of the road. They can be especially helpful if anyone in the family has asthma or allergies.
Where to place an air purifier
The machine cleans and circulates all the air in the room. So the only thing that matters is not to place it too close to the wall or furniture. You want 10cm around it on all sides to guarantee airflow in and out of the air purifier.
Room-wise, if you pick one room, pick the bedroom. You spend about a third of your life in there, hopefully with the door shut (which is better for fire safety, too). The clean air will help promote deep sleep, as well as being good for your health.
Do air purifiers remove smells?
Air purifiers that use activated carbon filters will remove the Volatile Organic Compounds (VOCs) that cause smells. That could be a musty smell or the particulates from a scented candle or aerosol.
How long does it take for an air purifier to clean a room?
It depends not just on the air purifier but how big the room is. Measure your floor space and look for a machine that promises to clean the air in a room of that size five times an hour. Which means it filters all the air in the room once every 12 minutes. Machines sometimes claim to clean large spaces but then they only promise to clean the air a couple of times an hour.
How much should I spend on an air purifier?
For one room: £150 and look at the Blueair 411, which outperforms others that cost more. Budget £500-700 if you want to clean the air in a much larger space.
What are the different types of filter and which do I need?
The more stages of filtration, the better, to remove different sized particles.
- Dust pre-filter – think of air filtration like sifting sand on a beach. You want to remove the large pebbles first with a big sieve before using a finer one. Otherwise, the fine filter gets clogged up.
- HEPA filter – this catches more dust, pollens, other allergens, even bacteria, so you’ll breathe cleaner whether you suffer from pet allergies or hay fever. Our PM10 test results are a measurement of particles no bigger than 10 microns wide.
- Electrostatic filtration – this charges small particles so that they stick more easily to the filters.
- Active carbon – this is great for very small particles from traffic fumes, cigarette smoke and the Volatile Organic Compounds (VOCs) that carry unpleasant smells. They can even remove viruses from the air. Our PM2.5 test results are a measurement of particles no bigger than 2.5 microns wide, which includes much tinier particles.
How do I get the right-sized machine for my room?
Measure your floor space in m². Then pick a machine that promises to clean the air in the room five times an hour. Ceiling heights are pretty consistent so this is accurate enough. If you enjoy maths homework then you can measure the volume of the space in m³ and look at the Clean Air Delivery Rate (CADR) of various machines to see which suits you best.
What else should I think about when buying an air purifier?
Noise if you’re sensitive to it, measured in decibels (dB). If you want a discreet air purifier, consider a machine that’s quiet on its lowest setting. Or one with an auto mode that is quiet unless it needs to scrub the air more, which is unlikely in the middle of the night.
Sleep timers are ok for the bedside but surely it’s better to have a quiet machine that you can leave on, so the air is clean all night.
How we test our air purifiers
Our testers Caramel and Caroline have decades of experience of reviewing technology products between them. Writing for, among others, The Evening Standard, The Express, The Guardian, The Independent, The Mail on Sunday, The Sunday Mirror, The Telegraph and The Sunday Times, Caramel has long been part of the Ideal Home family and knows exactly what you’re looking for in an air purifier.
London’s air pollution, along with two tweens and a dog, meant that the air in Caramel’s house needed a good scrub. She tested each machine rigorously at home, taking into account the size, price, controls, features and noise levels as well as the all-important air purification performance.
Performance was tested using expensive high-end industrial equipment, namely the Met One Instruments Model 804 Handheld Particle Counter. For each air purifier, Caramel tested the room’s initial air quality and then tested it again after the air purifier had been used at its top setting for an hour.
Finally, she compared the two sets of results to establish how well the air had been cleaned.
She focussed on the PM10 and PM2.5 figures for our test because these are the ones the World Health Organisation uses as benchmarks of air quality. These are particles measuring no more than 10 microns and no more than 2.5 microns.