1. The quick list
2. Best air purifier overall
3. Best value for large rooms
4. Best smart air purifier
5. Most energy-efficient
6. Best for technology buffs
7. Best value for small spaces
8. How we test
9. How to choose
Looking for the best air purifiers? Look no further. We’ve tested 10 different models to find those that deliver the best of everything, from efficiency in filtering the air, to an easy to use design. Our overall winner is the Blueair Blue Pure 211+ Auto; this model achieved the top scores for performance, with high ratings for filtering smoke, dust and pollen. It would suit a large room and is very easy to use with single button operation. But, it still offers three fan speeds, as well as an auto and night mode. You can’t ask for much more.
As part of this test, each model’s Clean Air Delivery Rate (CADR) was assessed and compared using the AHAM AC-1 testing method. Certification to prove the results was required — if that was missing, we sent the models off to the lab to find out for ourselves. On top of this, each model was assessed in our tester’s home. We took account of the noise, power, ease of use and general design. If a compatible app was available, we checked the ease of navigation as well as the features on offer here too. Everything from the length of the cable, to the data provided formed a part of this test. That’s how you know you can trust our results. Read on to see the winners for the best air purifiers.
The quick list
Already know what type of air purifier you’re looking for? Here’s a quick list of our winners for every category, so you can jump right into the reviews. This can save you some time if you already know that you need a compact design, or one which will offer smart capabilities. If you’re not sure what you want, scroll on to see our list in full.
The best air purifier overall
The best air purifier overall in our tests, we recommend this model above all others because it gets the job done quickly and efficiently, saves energy and works well in large spaces.
The best value for a large room
The perfect option if you're shopping on a budget, but need an air purifier which can handle a large space. While it’s not exactly pretty, it will get the job done.
The best smart air purifier
The best air purifier for anyone who wants smart connectivity and remote control via an app. There's a useful LCD screen built into the device itself.
Most energy-efficient air purifier
Small and compact in stature, this air purifier comes with a useful eco setting which will keep energy costs low. It provides a decent clean air delivery rate (CADR) as well.
The best air purifier for technology buffs
This air purifier stands out for featuring “Plasmawave” technology. It creates Hydroxyls to tackle any unwelcome airborne particles. Plus, it comes with a useful remote control to change settings from afar.
The best value for small spaces
This compact air purifier is ideal for rooms up to 190 sq ft. It’s simple to set up and great value for money considering how efficiently it cleans the air.
The full list: Best air purifiers
✅ You want a strong air purifier: This air purifier achieved an average CADR of 360 across dust, smoke and pollen — the highest rating of those I tested. By comparison, the Dyson Pure Cool TP01 reached an average of 71. This means the Blueair Blue Pure 211+ can handle rooms up to 550 sq ft.
✅ You want ease of use: The Blueair Blue Pure 211+ Auto comes with enough features to suit everyday operation, including three fan speeds, an auto mode and a night mode. It’s very straightforward to operate and not overly-complicated in its design.
✅ You want to customize your air purifier: The skirt on the lower half of this air purifier comes in several colors, including pink, blue, green and gray, so you can customize it to suit your décor or personality.
❌ You’re tight for space: This air purifier measures 20 x 13 x 13 inches and weighs 12.5 pounds, so it's a hefty design which will take up some room. It will be more obvious to the eye at this size as well.
❌ You want a strong night mode: Night mode effectively dims the lights on the unit and slows the fan down to reduce noise, but I found it to be on the weak side, so you might end up running the standard settings to get a satisfactory performance.
❌ You’re conscious of noise: While the Blueair Blue Pure 211+ Auto runs quietly at its lowest setting, it's among the noisiest at its fastest setting. It’s not particularly noisy on the whole, but this is something to be aware of.
The Blueair Blue Pure 211+ Auto will suit most households. It’s a substantial air purifier, and offers first-rate air purification capabilities alongside a premium and simple-to-operate design. There’s enough settings to cover the basics, it's attractive, and can be customized to your liking.
What you need to know: Throughout these tests, one cube-shaped air purifier stood out above the rest. The Blueair Blue Pure 211+ Auto dominated the competition. This medium-sized air purifier will suit rooms up to 550 sq ft. It features an upright cuboid design, with a plastic upper section and a skirt fitted around the base, which acts as a pre-filter and comes in several colors. A HEPASilent filter is included, which uses both a carbon and particle layer. For me, it looked like a futuristic robot, which has a quality appearance compared to the competition. There are three fan speeds on offer as well as an auto function, plus a night mode is included for dimming the lights.
Design: This model provides enough settings to cover basic necessities. The three fan speeds offer a decent range, and the auto function means it’s able to self-adjust the speed to suit the quality of the air. As a consequence, this air purifier will only use as much energy as required. The night mode is a useful function, but I did find the power more lackluster than I would have expected on this setting.
Performance: This air purifier scored best for its CADR; achieving 353, 347, and 380 respectively for smoke, dust and pollen. That means it will make quick work of all sizes of airborne particles. It also means it can handle a decent room size of 550 sq ft — making it more than adequate for a large bedroom or living room. It scored average marks for noise produced, as it was fairly quiet on its lowest setting (35.6db), but on the noisier end of the spectrum at its loudest (60.8db). It was reasonable in terms of electricity consumption as well, using only 0.159 kWh over the course of 24 hours on auto mode. By comparison, the Levoit Core 300 required 0.7 kWh over the same period.
Ease of use: This air purifier is very easy to use with one button to cycle through every setting — although the air quality indicator light is less than obvious with a blue light meaning good, and red meaning bad, and orange somewhere in between. Changing the filters couldn’t be more simple either, just remove the top of the device via the buttons on each side. Changing the filter is one of the 7 ways to get more out of your air purifier.
Value for money: At around $300, this air purifier isn’t the cheapest, but it’s also not the most expensive. The Coway Airmega AP-1512HH by comparison is $200, while the Blueair HealthProtect 7470i will set you back over $450. Replacement filters are $70 though, which is pricey.
Read the full review: Blueair Blue Pure 211+ Auto
| Attributes | Notes | Rating |
|---|---|---|
| Price | At $300, this air purifier is average | ★★★☆☆ |
| Design | Offers the basics, but lacks extra features | ★★★★☆ |
| Performance | Top of the class | ★★★★★ |
| Ease of use | Straightforward and user friendly | ★★★★★ |
The best value for a large room
✅ You need to cover a large space: This air purifier will suit rooms of up to 465 sq ft, which is pretty sizable. And thanks to its CADR scores of 300, 320 and 300 for dust, smoke and pollen respectively, it will filter your air both quickly and effectively.
✅ You want good value for money: Considering its price of $150 and the capacity of 465 sq ft, this air purifier is excellent value for money. Plus the replacement filters only cost around $40, which is good value as well.
✅ You want something easy to use: The touch-based control panel on top of this air purifier is very easy and intuitive to operate. Plus there’s a quick reference guide included to help get you started.
❌ You want an auto mode: This air purifier lacks an auto mode, which means it will stick to whatever fan speed you set it to, rather than adjusting based on the quality of the air. That means you could be using more or less power than is actually necessary.
❌ You want to save on energy: The Honeywell HPA300 consumed a lot of energy during my tests — using 1.002 kWh over 24 hours on the standard setting. This was the highest energy reading I'd seen in these tests, and translates to over $40 a year.
❌ You like peace and quiet: This air purifier is quite a noisy operator, producing some of the loudest decibel readings in my tests on both the lowest and highest settings (41 and 59.6dB).
The Honeywell HPA300 might not be the prettiest to look at, but it’s straightforward to operate and will get the job done. Just keep in mind there’s no auto mode, and it’s not ideal in terms of noise or energy consumption.
What you need to know
The Honeywell HPA300 is a bulky beast of a device that offers strong performance considering its reasonable price. It’s a large oval air purifier with slats all around, measuring 22.3 x 20.0 x 10.8 inches. It’s pretty heavy at 17 pounds, and I found the exposed lip on the base was sharp enough to scratch your legs as you move it. So this is the kind of air purifier you won’t want to move around once you set it down. It suits rooms up to 465 square feet, making it ideal for larger spaces.
Design: Its settings are admittedly limited, offering four different fan speeds (including a turbo mode), as well as a timer for two, four or eight hours. There’s also the option to dim the device for night time operation. Indicators are included to check the three HEPA filters and activated carbon pre-filter within. However, there's no auto mode, which is a shame, so you'll have to manually change the fan speeds.
Performance: A truly powerful device, the HPA300 scored second to the Blueair Blue Pure 211+ auto on the CADR test. With an average CADR score of 300, 320 and 300, it performed slightly better on dust versus pollen and smoke and would suit rooms of up to 465 sq ft. However, that performance comes at a price, because it consumed more energy than any other air purifier I tested, at 1.002 kWh over 24 hours, and it was on the noisier end of the spectrum, producing 59.6 dB on its loudest setting. The Blueair HealthProtect 7470i produced just 48dB on its highest fan speed by comparison.
Ease of use: Air purifiers don’t get much easier to use, with a touch-based control panel and a quick reference guide to remind you of the basics. However, setting up this air purifier at first and replacing the HEPA filters when required is admittedly fiddly. I found fitting the front cover back into place to be awkward.
Value for money: Ultimately, at $150, this air purifier is a good value for the money up front, and the replacement filters are also a good price at $40. However, it’s worth keeping the cost of energy in mind to run this machine to get that amazing performance. You could end up paying back for it over time with regular use.
Read the full review: Honeywell HPA300
| Attributes | Notes | Rating |
|---|---|---|
| Price | Great price overall, but energy use is high | ★★★★☆ |
| Design | Simple and adequate, but no auto mode | ★★★☆☆ |
| Performance | Strong CADR, but poor energy and noise ratings | ★★★★☆ |
| Ease of use | User friendly and intuitive | ★★★★☆ |
The best smart air purifier
✅ You want a good performer: This air purifier scored 270, 275, 280 for its CADR with smoke dust and pollen respectfully. This puts it in the higher end of the spectrum for those I tested.
✅ You want more data and features: This air purifier provides plenty of data on its LCD screen, including the local temperature, filter lifetime remaining, and the relative humidity of the room. Plus, it offers smart connectivity so you can control it remotely.
✅ You want a quiet operator: The Blueair HealthProtect 7470i scored well for noise produced, reaching only 35.3 dB on its lowest setting and 48dB on its highest. The night mode helps reduce noise and light in the dark as well.
❌ You have a budget: This is one of the more expensive air purifiers I’ve tested, with an MSRP of over $750, although it can often be found on sale at around $500. Replacement filters will set you back $90 as well.
❌ You care about energy consumption: While it’s not as bad as others I tested, the Blueair HealthProtect 7470i still consumed 0.241 kWh over 24 hours, which is more than average. So all that extra data does take its toll.
❌ You want a portable air purifier: At 27.6 pounds, you’re not going to want to move this air purifier around often. While it does come with a pair of wheels to help with the task, it’s still cumbersome to shift to a new location.
Blueair’s HealthProtect 7470i has all the technological bells and whistles anyone could ever want, including smart connectivity and extensive data on the air quality. It also provides an impressive performance when it comes to air purification, and is quiet in use, making it ideal for those who need to concentrate. However, for all of this it’s quite an expensive and heavy device.
What you need to know
The Blueair HealthProtect 7470i offers a very modern and sleek design, with a white casing measuring 27.2 x 11.8 x 11.8 inches. In my opinion, it looks like it's straight out of a science fiction film. It’s the heaviest air purifier I’ve tested, weighing 27.6 pounds — so it’s not the one for you if you’re after something portable, despite the built-in wheels to help with this. I found it overwhelming and cumbersome to move around. It comes with an abundance of features, including smart connectivity, which allows you to monitor and control it via your phone, and would suit rooms of up to 418 sq ft.
Design: This air purifier comes with three default fan speeds, although the app will give you access to more, as well as an auto and night mode. It’s got an LCD screen on top of the device that gives you up-to-date information on what it’s sensing including the local temperature, filter lifetime remaining, and the relative humidity of the room. Plus, with two lights on the front — one representing gas pollutants and the other for larger particles — this air purifier has the clearest indicator of air quality I’ve seen and it's quite satisfying to watch it change in real time. It comes with a unique HEPASilent Ultrafilter as well as a “GermShield” mode that claims to activate when it’s in a “germ-prone environment”.
Performance: With a CADR of 270, 275 and 280 across smoke, dust and pollen, this air purifier is a strong performer which will suit rooms of up to 418 sq ft. It would perhaps suit those who struggle with pollen allergies the most due to its excelled performance in this field. Even though it is the quietest of the bunch at just 48dB on its highest setting, it’s also worth mentioning that it tends to use more energy than other devices at 0.241 kWh in 24 hours, so all that data comes at a cost. The app does improve the overall performance though in terms of better accessibility and additional settings — one feature solely possible through its app is the capability to dim all the lights while keeping the fan at a particular setting.
Ease of use: This air purifier offers more information than most, so the monitor on top will take some getting used to. However, it’s fairly intuitive to operate, and the filter is easy to change. The app itself is also very simple to use and every feature is conveniently located on one page. Its quick to navigate and deduce the current conditions of the room across different PM sizes.
Value for money: This is no doubt an expensive air purifier — at over $750 MSRP, it’s more than twice the price of the current winner. And the replacement filters aren’t exactly cheap either at $90. However, it is a very good air purifier, which provides more information than you can get from most. Value for money depends on how much you value that information.
Read the full review: Blueair HealthProtect 7470i
| Attributes | Notes | Rating |
|---|---|---|
| Price | Expensive, but a quality product | ★★★☆☆ |
| Design | Plenty of settings and data on offer | ★★★★★ |
| Performance | A strong contender, but with high energy use | ★★★★☆ |
| Ease of use | Straightforward, but lots to explore | ★★★★☆ |
Most energy efficient air purifier
✅ You care about energy consumption: The Coway Airmega AP-1512HH had the best energy score of all those tested, at just 0.082 kWh over 24 hours. This equates to a cost of just over $3 a year depending on your provider.
✅ You’re stricken for space: With a footprint of just 16.8 x 18.3 x 9.6 inches, this is a compact design which won't take up too much floor space. It has a thin and square build.
✅ You want adequate settings: While it’s a compact design, it’s not lacking in settings. An auto mode is included, so it will self-adjust the fan speed depending on the conditions of the room, and it comes with an eco mode which lets it power off when not required.
❌ You want to move it around: While the design is indeed compact, it’s still plenty heavy enough at 12.3 pounds. The Blueaur Blue Pure 411 Auto weighs just 8.3 pounds by comparison.
❌ You want peace and quiet: This was a noisy air purifier compared to others I tested, measuring 36.8dB on its quietest fan speed and 58.3dB at its loudest. So this isn’t one to get if you intend to work in the background.
❌ You care about costs: While the air purifier itself doesn’t cost a huge amount, the replacement filters will set you back $40 at a time. That’s about 20% of the initial cost.
There’s no denying how much the Coway Airmega AP-1512HH looks like an iPod Shuffle, but if you don’t mind that outdated Apple aesthetic, it’s a great air purifier. It offers an adequate CADR, comes with plenty of settings and uses minimal energy. Just keep in mind that it’s a little noisy and that replacement filters aren't cheap.
What you need to know
The Coway Airmega AP-1512HH offers a smaller footprint than those listed so far, measuring 16.8 x 18.3 x 9.6 inches. Don’t mistake this for meaning it’s more portable though, as it still weighs 12.3 pounds — this isn’t easy to lug around despite the included handle. While compact, it will suit rooms of up to 384 sq ft. For me, it's appearance is more in keeping with a hotel or office versus a modern home, but it's performance is worth considering.
Design: There are five different fan speed options to choose from, including useful auto and eco modes. While auto mode allows it to automatically adjust its fan speed depending on the current quality of air, eco mode will switch it to standby if it senses no change in the conditions of the air for a period of time. There’s also a specialized Ionizer option on top, which will disperse negative ions to improve the quality of the air it filters. In addition, there’s a timer for one, four and eight hours, and an indicator to change the carbon and HEPA filters. Lastly, an indicator light shows the current quality of the air. There’s no night mode, but you can dim the lights by holding down the Ionizer button.
Performance: It achieved a CADR of 247.5, 232.3, 241.3, with a similar performance across smoke, dust and pollen. While this is a little lower than those mentioned above, it’s worth accounting for the size difference, which is why this air purifier features so high on the list. It was also top of the class for energy consumption, requiring just 0.082 kWh over 24 hours. Taking account of the eco setting as well, air purifiers won’t get much greener. Where it falls down however is noise — it produced 36.8dB on the lowest setting and 58.3dB on its highest, which is pretty surprising considering the size. Having said that, a colleague bought this air purifier for her allergies — and it’s changed her life.
Ease of use: It’s very straightforward to set up and operate, with the buttons on the control panel clearly labeled and responsive. This air purifier makes cheery beeps and chimes as you operate it too, which I found comforting. It’s compact enough to hide it out of sight when required.
Value for money: The air purifier itself will set you back $170 up front, which isn’t bad. Running it will be equally cheap with a very low energy consumption. However, the replacement filters do cost $40 a pop, and will need changing every six months to a year. So this is worth bearing in mind.
Read the full review: Coway Airmega AP-1512HH
| Attributes | Notes | Rating |
|---|---|---|
| Price | Good price up front, but expensive filters | ★★★★☆ |
| Design | Plenty of settings, but heavy | ★★★☆☆ |
| Performance | Good considering the compact design | ★★★★☆ |
| Battery life | Very straightforward | ★★★★★ |
Best air purifier for technology buffs
✅ You want a remote control: A remote control is included with this air purifier, so you can adjust its fan speeds, activate the auto mode and power it on and off from afar.
✅ You want unique technology: This air purifier features “Plasmawave” technology. The premise behind this is that it creates hydroxyls that easily attach to other molecules to neutralize the air faster.
✅ You want washable filters: Both the pre-filter and carbon filter layers on this model are washable, which means you can extend the lifespan, however the HEPA filter layer is not, so you will still need to buy replacements when necessary.
❌ You want to save money: While this air purifier comes with an average price tag, the replacement filters are $80 per set. So this will soon mount up the costs.
❌ You want an attractive air purifier: The design for the Winix 5500-2 is rather large and plain, with a plastic finish. It will not be in keeping with those who care about aesthetics.
❌ You care about background noise: This air purifier gets rather loud on its highest fan speed, measuring 59.8dB in my tests. It’s not so bad on its lowest setting, but the added noise when it’s working at its hardest may not suit some.
The Winix 5500-2 is more about practicality than looks. It comes with a handy remote control, so you don’t have to get up each time you want to switch it on or off, and there are enough settings to suit all kinds of needs, including a unique ‘Plasmawave’ function. It may not look the prettiest, but it offers a decent CADR and a user-friendly design.
What you need to know
The Winix 5500-2 likely won’t win any beauty contests with its appearance, measuring 23.6 x 15 x 8.2 inches with a black plain casing and vents scored across its front. But, in my opinion, it's more likely to blend in with your décor than drawer the eye, which is no bad thing. Plus, it’s still a strong performer, achieving a decent CADR across the board and featuring a design which is very accessible. And if you love unusual tech, the “Plasmawave” technology is sure to raise a few eyebrows. It suits rooms up to 360 sqft.
Design: The Winix 5500-2 comes with several settings, including an auto setting, a night mode and four fan speeds as well as an air quality indicator. There’s also a timer with one, four or eight hour options. The air quality indicator shines blue for good, amber for fair and red for poor, and when the auto function is selected it will adjust its fan speed accordingly. The remote control lets you adjust the fan speed from afar, however you can’t select the Plasmawave function, timer or night mode. This air purifier comes with a pre-filter and carbon filter layer, both of which are washable, and a HEPA filter. It’s worth flagging that it’s quite a heavy design, weighing 15 pounds, so you won't want to move it often.
Performance: In terms of CADR, this air purifier scored 232, 243 and 246 for smoke, dust and pollen. This puts it amongst some of the top performers of those I tested, especially for pollen. It was also the runner up for energy consumption, requiring only 0.105 kWh over 24 hours — so it won’t cost an arm and a leg to run. Noise was admittedly a little hit and miss; it was fairly quiet on its lowest setting at 35.3dB, however it reached 59.8dB at maximum, which was second only to the Blueair Blue Pure 211+ Auto at 60.8dB. In terms of the Plasmawave technology, I didn’t notice any specific change to the air purifier when it was activated. But, with such high CADRs, it does question its necessity.
Ease of use: This air purifier is very straightforward to use, made all the easier by the useful remote control. I didn’t even have to refer to the manual during testing. The filters just snap into place when they require replacing as well.
Value for money: The air purifier itself comes with an MSRP of $249, but you can often find it on sale for $159. This makes it reasonably priced, especially if you get it on sale. Running it is pretty cheap too because of the low energy consumption. However, with replacement filters costing $80, it could cost more in the long run.
Read the full review: Winnix 5500-2
| Attributes | Notes | Rating |
|---|---|---|
| Price | Good value, but with expensive filters | ★★★☆☆ |
| Design | Plenty of settings, but lacking aesthetics | ★★★☆☆ |
| Performance | Adequate and consistent | ★★★★☆ |
| Ease of use | Simple and convenient | ★★★★★ |
The best value for small spaces
✅ You want a compact design: This air purifier features a compact design which is ideal for smaller spaces. Measuring 16.7 x 7.9 x 7.9 inches and weighing 8.3 pounds, it’s portable and easy to store as well.
✅ You want some color: The pre-filter on the Blueair Blue Pure 411 Auto comes in a range of colors, including gray, pink, blue, and green. So you can match it to your décor or simply give it some personality.
✅ You want value for money: Priced at $139, this air purifier offers excellent value for money. Plus, replacement filters cost just over $20.
❌ You need something to suit a large room: This air purifier works best in rooms up to 190 sq ft, so it’s likely unsuitable for larger bedrooms or living rooms.
❌ You want a stable design: I noticed that this air purifier has a tendency to fall over if you program it with too much pressure. So keep in mind pets may easily knock it over too.
❌ You want seamless operation: While this air purifier is very easy to use, with one button to control everything, this can prove tedious. Essentially, if you miss the setting you want, you will have to cycle back through everything to land on it again.
The Blueair Blue Pure 411 Auto is the answer if you need an air purifier to suit a smaller room. While its CADR readings aren’t as high as others on the list, it’s still more than capable of adequately cleaning up to 190 sq ft. Plus it offers all of the settings you need, including an auto function.
What you need to know
The Blueair Blue Pure 411 Auto offers a small and effective design, measuring 16.7 x 7.9 x 7.9 inches while suiting rooms up to 190 sq ft. It has a neat and pleasing appearance — looking somewhat like a large battery with a fitted pre-filter skirt and a single button on top. There’s a range of pre-filter colors available, including pink, blue and green, so this could easily suit a kid’s bedroom. Size and portability is one of the 10 things you need to know before buying an air purifier.
Design: While it has one button to control everything, this air purifier still has plenty of settings. There are three fan speeds, the lowest of which acts as a night mode and a separate auto setting. There’s a light on the front to indicate the quality of the air and the button on top also acts as a filter replacement indicator. The only thing that’s really missing is a timer, so you can't set it and leave it, but otherwise you have everything you need. Inside, you will find a HEPASilent and carbon filter to deodorize.
Performance: The performance may not seem strong with CADRs of 123, 107 and 96 across smoke, dust and pollen. However, low CADRs do not necessarily equate to a poor product, they just mean it won’t suit larger spaces. So, as long as the room is no more than 190 sq ft, you can expect a premium performance. I also found this air purifier to be quiet in operation (51.6 dB at max) and energy efficient (consuming 0.154 kWh over 24 hours), so what’s not to like?
Ease of use: With one button to control everything, ease of use couldn’t be more obvious. Although you will have to cycle through if you miss a setting, which I found a bit tedious. I found that it tipped over easily when programming with too much pressure too, which could be a nuisance on carpet. The filters are easy to switch out when needed though.
Value for money: This air purifier costs just $139, which makes it pretty great value — although keep in mind it is only designed to manage a small space. Filters cost $20 as well, so upkeep is pretty minimal.
Read the full review: Blueair Blue Pure 411 Auto
| Attributes | Notes | Rating |
|---|---|---|
| Price | Good value up front and in energy costs | ★★★★☆ |
| Design | Plenty of settings, but no timer | ★★★☆☆ |
| Performance | Capable in a smaller space | ★★★★☆ |
| Ease of use | Straightforward with single button control | ★★★★★ |
How we tested the best air purifiers
In order to come up with a list of the best air purifiers, we first researched a number of models on other reviews sites and online retailers to identify some of the more popular models. We then narrowed our list down to 10 air purifiers that we decided to test for this roundup. Testing involved two steps: Lab tests and in-home tests.
Laboratory testing
We compared the CADR of each air purifier to get an accurate representation of the performance. If a CADR rating was not supplied by the manufacturer, we sent it off to a lab to get our own rating — we used SGS IBR Laboratories for this test. The lab calculated the CADR for each pollutant by using the AHAM AC-1 testing method.
This involves sealing the air purifier into a dedicated test chamber and then administering tobacco smoke, dust or pollen particulate into the atmosphere at a controlled rate. Each particle test would be conducted two times — once with the air purifier switched on and once where it’s powered off. The natural decay rate from external elements, such as gravity, can then be accounted for and subtracted from the air purifier’s performance to give a final accurate reading. Electronic particle-counting devices are used to monitor the condition of the air quality, breaking down what sizes of particles remain in the atmosphere, as well as how frequent they are.
Smoke, dust and pollen all represent alternate particle sizes and can help assess where the air purifier may excel or struggle. Smoke represents the smaller particles, accounting for 0.09-1.0 microns, while dust sits in the middle, from 0.5-3.0 microns. And pollen has a larger particle size of 0.5-11.0 microns.
The room size recommendation is based on the smoke readings from the CADR test. According to AHAM Verifide: ‘The Room Size in square feet is calculated based on the removal of at least 80 percent of smoke particles in a steady-state room environment, assuming one air change per hour with complete mixing in the room.’
This is a widely recognized testing protocol for air purifiers, and one of the few ways with which you can compare performance. For those brands that already provided a CADR, we checked they had the certificate to prove it. That way, we made sure each device got the same treatment. It should be noted that though a device may have a low CADR score, it doesn’t necessarily mean that it’s a bad air purifier. But, this does mean it will struggle in larger rooms.
"What makes a good air purifier in my opinion is striking the balance between utilising a filter (or series of filters / filtration mechanisms) that have good removal efficiency for contaminants in the air that we breathe, whilst allowing for high airflow through the air purifier. It is of limited use having an air purifier with extremely high contaminant removal efficiency if the air cannot be circulated through the purifier quickly. Very high efficiency filters tend to have high airflow restriction, so it really is key to get that balance correct."
In-home testing
We then conducted a home test separately to compare the design and ease of use of each air purifier in a real world environment. For energy, we hooked up each device to an electricity usage monitor and ran it for a full 24 hours. To figure out the noise output, we used a decibel meter and ran the purifiers at a set distance of three feet away on both the lowest and highest possible fan settings. We also took an ambient room reading to make sure that the fan noise was not being overpowered by the outside world.
We considered all kinds of factors as part of these in-house tests, from the length of the cord to the plug, to whether the model oscillates. The overall set up and the clarity of the manuals was taken into account as well. With all of this, we were able to create a scoring system to summarize the overall experience. Once all these scores were totted up, we got the average ratings that you see above.
Why are there no Dyson air purifiers in our list?
We tested the Dyson Pure Cool TP01 air purifier to the same standard as those above, and unfortunately it did not deliver a comparable standard of performance. Our lab tests revealed a CADR of 71.7 for smoke, 68.5 for dust and 72.8 for pollen. These were the lowest CADR scores of all of the air purifiers we tested, with only IKEA’s FÖRNUFTIG air purifier coming close.
In accordance with these ratings, the Dyson Pure Cool TP01 is recommended for room sizes up to 111 square feet, which is minimal and impractical for most homes. It’s certainly appealing for its unique appearance and modern design, plus it offers some useful features such as a separate remote control and 10 fan speeds.
However, considering its price of $399.99, we were expecting more in terms of features. There’s no auto setting, which most air purifiers offer nowadays. This allows the air purifier to adjust its fan speed in accordance with the current condition of the air. Without it, you need to adjust the speed manually and potentially waste more energy than necessary. There’s also no smart connectivity or night mode, which is a big disappointment — you need to upgrade to the TP02 model ($499.99) to get all of the above. The Blueair Blue Pure 211+ Auto costs less by comparison, and comes with an auto as well as a night mode.
As a result, the Dyson Pure Cool TP01 didn’t make the cut, and missed featuring in our best air purifiers list. It’s a great-looking fan, but we wouldn’t recommend it as an air purifier based on the CADR results.
In response to this result, Dyson issued the following statement: “CADR is a measurement of how fast a purifier can clean the air in a small, controlled chamber that has one sensor and a fan to circulate the air. Dyson feels that assessing purification performance by the CADR test alone can sometimes be misleading to consumers because the numerical result is unrepresentative of performance in a real-world environment. Our philosophy is that to truly purify a whole room properly a purifier needs to automatically sense pollutants, capture them effectively, and project clean air to every corner of a large room, representative of real homes. We champion testing that evaluates all three aspects of purification performance rather than focusing solely on speed. Dyson engineers spent years developing such a test (that we call the POLAR test) that more accurately represents a real home to assess how well purifiers clean the entire room. Based on the POLAR test, Dyson Purifiers are rated ‘Excellent’ as are some others available on the market. An air purifier achieves an 'Excellent' rating in the POLAR test if it can reduce PM2.5 particle concentration below 12 μg/m3. This is based on the US EPA's 2012 annual PM2.5 exposure standard.”
CADR Results
| Air purifier | Suggested room size (sq. ft.) | Smoke CADR | Dust CADR | Pollen CADR |
| Dyson Pure Cool TP01 | 111 | 71.7 | 68.5 | 72.8 |
| IKEA FÖRNUFTIG | 141 | 90.7 | 79.9 | 88.6 |
| Blueair Blue Pure 211+ Auto | 550 | 353 | 347 | 380 |
| Blueair Healthprotect 7470i | 418 | 270 | 275 | 280 |
| Blueair Blue Pure 411 Auto | 190 | 123 | 107 | 96 |
| Coway Airmega AP-1512HH | 384 | 247.5 | 232.3 | 241.3 |
| Honeywell HPA300 | 465 | 300 | 320 | 300 |
| GermGuardian AC5250PT | 189 | 122 | 132 | 138 |
| Levoit Core 300 | 224 | 144.5 | 138.6 | 142.2 |
| Winix 5500-2 | 360 | 232 | 243 | 246 |
Air purifier sales and deals
Want to invest in a new air purifier? Check out our air purifier sales and deals page first to grab a bargain. Some of our favorite brands have made an appearance, so it’s worth keeping an eye on.
Frequently asked questions
Is an air purifier actually worth it?
While air purifiers are designed to neutralize and sanitize air pollution, its performance and worth depends on the model you own. Not all air purifiers are suited to remove every allergen, so it's important to check the product description for a clean air delivery rate (CADR). The higher the CADR, the most effective it is of trapping airborne particles. Similarly, air purifiers with a high-efficiency particulate air (HEPA) filter is a good indicator of having a high CADR. In any case, air purifiers are much more effective than houseplants when it comes to cleaning your air.
If you find an air purifier with a proven performance in terms of CADR and its suited to the allergens you want removing, you've got the best chance of it making a difference to your home environment. However, if you want to see the actual impact your air purifier is making, you can always opt for a model which displays live data, either on the air purifier or on your phone, such as the Blueair HealthProtect 7470i.
What exactly do air purifiers do?
If you want to know how do air purifiers work, essentially each utilizes a powerful fan that sucks in air to go through one or more filters (HEPA). These filters trap and neutralize particles and pollutants as air passes over them before the air is recirculated. Some air purifiers also have ultraviolet filters and use light to destroy smaller molecules such as mold and bacteria.
If you want to go above and beyond, also check out our tips for reducing allergens in your home. Plus, here are 9 ways to fight allergy season.
Do air purifiers help with Covid?
Although there haven’t been any specific air purifiers tested against the Covid-19 virus, the CDC recommends most top-rated air purifiers have efficient filters capable of capturing pesky, particles similar to coronavirus, and “can help prevent virus particles from accumulating in the air in your home”.
Where is the best place to put an air purifier in your room?
The wrong positioning can hinder the performance of even the best air purifiers. Whichever room you place your air purifier in, you need to make sure it’s facing the open space, with no immediate obstacles in sight. This is a necessity because your air purifier needs space to ‘breathe’; it needs to effectively suck the air in and then vent it out. If your air purifier is hidden behind the couch, it’s going to be stifled and won’t effectively clean the air. Should power outlets limit the reach of your air purifier, consider buying an extender — this optimum placement is essential to get the best performance.
If you’re thinking about buying an air purifier, bear in mind that this does mean it will be on open display in your room. You might want to opt for a design which is aesthetically pleasing or matches your décor as a consequence. For instance, you can replace the color of the exterior skirt on the Blueair Blue Pure 211+ Auto to suit your taste. Don’t buy a design that’s bigger than necessary for the same reason. If it’s only a small room, you don’t want a chunky design out in the open, taking up valuable space. While looks are important, don’t forget that performance always comes first, which is where our tests can help. There’s no point in buying an attractive air purifier if it makes little difference to the quality of the air.
Should I get a smart air purifier?
Some modern air purifiers, such as the Blueair Health Protect 7470i, can be connected to the Wi-Fi and linked to an app on your smartphone. In doing this, you can control the air purifier remotely, including changing the fan speed or setting a schedule. For some air purifiers, the app will also breakdown the quality of the air and let you monitor it more precisely.
This can give you a much better understanding of what’s in your air and you can see the effect the air purifier is having on it too. Using the Dyson air purifier app for instance, you can see the different levels of particulate matter as well as any volatile organic compounds (VOCs) and nitrogen dioxide. This is usually displayed in a chart form so you can see where there’s been an increase in any air impurities.
This can be a useful feature to have, particularly if you want to better understand your air and want to source where your allergies are coming from. It’s also nice to see the evidence that the air purifier is making a difference.
Some apps will even display what the air is like outside as well, so you know not to leave when the pollen count is high or the general air quality is low.
Is there a downside to air purifiers?
Every appliance has its drawbacks, and air purifiers are no exception. First, these can be chunky, sizable appliances, particularly if you get a model which is suited to a large room and place it in a small space. Thankfully, compact designs are available to reduce this problem. Air purifiers also need to be placed quite centrally, which means they can become an eye-sore if you don’t find the design attractive. Some designs look more modern than others and this is something to take account of when picking one out. Some models can even be customized to suit your décor, such as the interchangeable skirts on the Blueair air purifiers.
There’s also the overall cost to consider — air purifiers can cost as much as $1000 if you opt for the latest features and additional functions, so this can be a substantial investment. Budget options which perform just as well are available though, as our tests show. Many forget to account for how much these appliances cost to run though — some consume much more energy than others and can consequently cost a lot in the long term. Try to find an option with eco settings, or an automatic sensor, so as to only use as much power as necessary.
In terms of expenses, your air purifier will need new filters on occasion, so you will need to replace these as and when necessary. Always check how much the replacement filters cost, as well as how long they last, before you make a purchase. That way you know the likely costs in the future.
Air purifiers will naturally make some noise as they work. This can’t be avoided as a fan needs to run to rotate the air. Some may think of this as a real nuisance, particularly if they’re intending to sleep through it at night. But, some models do run more quietly than others, as our tests prove, and you can also opt for an air purifier which features a night mode to lower the fan speed and reduce the lighting on the appliance.
While the above are all drawbacks to be made aware of, don’t forget about the positive impact an air purifier can have on your day-to-day life. It can ultimately help you breathe easier at home, reducing allergens as well as odors. It’s also worth flagging that a lot of these problems can be offset by choosing the right air purifier. By selecting an appropriate design, which will effectively reduce the pollutants in your home, the positives will far outweigh the negatives.
How do I know if I need an air purifier?
Air purifiers are purchased predominantly by those who suffer from allergies in their home. Depending on the specific allergy and its severity, this can cause all kinds of symptoms, from sneezing, to a blocked nose, to struggling to breathe. It can contribute to difficulties when sleeping at night as a consequence.
Air purifiers can help reduce dust, pollen and pet dander from the air. Some claim to filter viruses from the atmosphere too, which can be a prime selling point if you’re wary of airborne diseases at home. If the air purifier has a carbon filter, which most do nowadays, it can actively deodorize as it works as well. So, it’s a useful purchase should your kitchen smell from residual cooking.
You don’t need to suffer from allergies to take advantage of an air purifier though. Air purifiers can improve the air quality at home in general, reducing the level of pollutants you breathe.
In fact, according to The White House: ‘Cleaner indoor air improves cognition and productivity, reduces the spread of other airborne diseases, protects against outdoor air pollutants such as smog and wildfire smoke, and decreases the number of environmental triggers for conditions like asthma and allergies.’ So whether you suffer from allergies or not, an air purifier can help to improve conditions at home.
How to choose the best air purifier
If you’re buying an air purifier, there are several factors to consider. First, you want one which is simple to operate, with enough fan speeds to suit your needs. You also need one which will suit you space and work effectively — take a look at the suggested room size and CADR figures for guidance. Generally speaking, the higher the CADR, the better, although it may not be necessary if you’re purifying a small room. It’s also useful if your air purifier can display the live quality of the air, and adjust automatically to it — that way you don’t have to keep changing the settings yourself. Night modes are handy as well if you intend to use the appliance as you sleep.
“Blueair recommends choosing an air purifier capable of changing the air in your room five times per hour. To get the correct size, determine the square footage of your room. If this is your first air purifier, we recommend starting with the room you sleep in, where your family spends the most time, or if you cook a lot, perhaps your kitchen. Look at the CADR (Clean Air Delivery Rate), which is an industry standard that tests how much air can be cleaned and how fast clean air can be delivered. We recommend an air purifier certified by the Association of Home Appliance Manufacturers (AHAM Verified® with the highest possible CADR). In addition to performance, other considerations when picking an air purifier may be energy efficiency, quietness, and design.”
CADR ratings
The effectiveness of an air purifier can be measured by the CADR (Clean air delivery rate). This number reveals its performance depending on a particular room size. The higher the number, the better it is at clearing airborne particles and the more effective it is at cleaning a larger space too.
The numbers translate to how many cubic feet of air the purifier can clean per minute. The standard goal is to clean a full room’s worth of air in 15 minutes. So, for instance, a 300-square-foot room would need an air purifier with a CADR of 200 or so, assuming ceilings were 10 feet high and any doors and windows were closed.
Some air purifiers come with different CADRs for smoke, pollen and dust, so you can see which it is most effective for. Not every purifier is tested using the CADR rating system, but real-life reviews can give you a sense of a device's effectiveness if a rating isn't available.
Here are the minimum CADR ratings the Environmental Protection Agency recommends by room size:
| Area (sq. ft.) | Minimum CADR (cfm) |
| 100 | 65 |
| 200 | 130 |
| 300 | 195 |
| 400 | 260 |
| 500 | 325 |
| 600 | 390 |
Filter types
In general, you'll want to look for a purifier that uses a true high-efficiency particulate air (HEPA) filter.
Government agencies and professional groups, including the EPA and the American Lung Association, recommend True HEPA filters as the standard for air purification. These filters trap 99.97% of particles that are at least 0.3 microns in size.
Some devices have HEPA-type filters, which work similarly but aren't held to the same performance standards. The IQAir HealthPro Plus uses a HyperHEPA filter, which is believed to capture even smaller particles than a True HEPA filter.
Your purifier will likely also come with a pre-filter (some you can clean, some you have to toss after a few months) that catches the big stuff like pet fur and human hair before it reaches the main filter.
Some devices have additional filters, like carbon or charcoal filters, that trap the petroleum-based gases known as volatile organic compounds (VOCs). Carbon filters also act as natural deodorizers, which makes them suited for the kitchen, too.
Noise levels
Air-purifier noise levels range from nearly silent to steady humming, like an AC unit. Depending on the fan speed you're using and where you're placing your purifier, you may prefer a quieter device.
Many of us aren’t aware of the added costs when running an air purifier. Firstly, you should consider the cost of replacement filters, then there’s the energy needed to power the appliance on a regular basis. In terms of the filter replacement, some models are fitted with filters which can last for years, but can be very expensive to replace. Whereas others can be cheaper, but a replacement is needed much more often. To calculate the actual cost, you need to balance out the frequency of changing the filter with the cost per filter. OneLife’s new air purifier never needs its filter replaced if you really want to save!
You should also take energy consumption into account. Some of the best air purifiers in our list are Energy Star Certified and these generally will save money in the long term. Bear in mind that different speeds and settings will affect how much energy it uses though.
If an air purifier is designed to reach a large room and it uses a powerful fan to do so, it is likely to consume more energy than a smaller model, although efficiency can vary. One setting worth looking out for is an ‘Eco mode’ — this should save on energy use and makes the product more sustainable in operation.
Extra features
Some features are more nice-to-have extras than absolute requirements. In general, pricier purifiers come with more features, such as filter indicator lights, dimmable lights and programmable timers.
Only one of the devices we recommend (the Winix 5500-2) comes with a remote control, but we're not convinced that this adds a lot of value to the machine.
Should I use an air purifier at night?
Whether you’re awake or asleep, the quality of the air you breathe will impact how you feel. It’s for this reason that running your air purifier at night is just as valuable as during the day. In fact, some will buy an air purifier for the sole purpose of nightly use. This is because our allergies can become more of a nuisance as we sleep — waking us up with itchy throats or blocked noses. With disturbed sleep, this can impact how we feel the following day as well.
Air purifiers are often placed in a corner of the bedroom to run quietly at night while we sleep. You’ll find many models will come with a night mode for this exact purpose. When activated, this setting will lower the fan speed and reduce the noise output, so you can sleep through its operation while still reaping the benefits of clean air. Any lights on the control panel will often dim to help you sleep soundly as well.
Just remember, using an air purifier through the night will require more energy consumption, so this will increase the running costs. Make sure you opt for an Energy Star certified model to keep your bills at a minimum. If your air purifier is working hard at night to clean your air, avoid leaving windows and doors open as well — otherwise, this is counterproductive. Alternate between the two, and only open windows when the pollution levels are low.
How much should you spend on an air purifier?
Air purifiers can vary in price substantially, starting from as little as $30 and ranging up to $750 for more premium brands. Of course, the more features and technology your air purifier offers, the more expensive it will be. For instance, the ability to feedback the current conditions or the impact its having on the air will likely add to the price tag. If smart connectivity is available, this too will make things more expensive, as will hybrid multi-functional designs. Some air purifiers will also function as humidifiers or heaters for greater versatility. Although, you are technically getting multiple appliances for this price, so its value depends on your use.
You don’t need to pay top dollar to get a good air purifier, as our tests show. As long as the air purifier is of a suitable size and provides an appropriate CADR as well as the functions you require, it will suit your space. It’s a good idea to make a note of what you need from your air purifier before you start browsing. Then, keep these specifications to hand as you shortlist models. In doing this, you won’t pay more than necessary for unwanted features. Have a budget in mind at the same time. This will also prevent you from overspending.
