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Editor’s note: Our top pick, the Blueair Blue Pure 311 Auto, is currently unavailable at most retailers. It is currently available at Amazon, but if it goes out of stock, you’ll be well-served by one of our other picks.
The amount of microscopic gunk—pollen, pet dander, bacteria, mold and viruses—occupying the air space in an average household can be startling. Regular furnace filter changes can help minimize your airborne roommates, but adding a standalone air purifier to the mix can aid in evicting those unwanted particulates.
The term “air purifier” might be a bit of a misnomer. It’s impossible to completely purify your home’s air. One of our experts, Jose-Luis Jimenez, Ph.D., who specializes in aerosols and atmospheric chemistry, prefers to call them air cleaners . Whatever you call them, not all air purifiers are built to the same standards, and only a few products are truly up to the task.
We tested several of the top air purifiers to see if they could handle the rigors of daily use. Our top pick is the Blueair Blue Pure 311 Auto , which performed incredibly well during our testing, comes in a sleek design and is remarkably easy to use. We also found the Levoit EverestAir to be a great option for shoppers seeking a premium air purifier, while the Coway Airmega 200M is the best lower-price option, and the Levoit Core 400S offers smart-home features at a more affordable price.
All four come with plenty of additional features to make them worthy additions to any home. Scroll down for more details on our picks for the best air purifiers, along with the experts we talked to and the tests we performed to make our selections.
Beyond its impressive ability to remove pollutants and its 360-degree design, the Blue Pure 311 Auto is one of the best-looking air purifiers available today.
The Blueair Blue Pure 311 Auto is a remarkably powerful air purifier with a smart design that looks great and is easy to use. Few products carrying a similar price tag manage to compete with the impressive performance—and none come close to matching its appealing design.
The Blue Pure 311 Auto’s efficacy was proven during our at-home testing, in which it outperformed just about every other air purifier we tested. Its 95.1% clearance rate was the best in its price range, and it even went toe-to-toe with products twice its price (including the EverestAir and Molekule Air Pro, with 98.6% and 95.4% clearance rates, respectively). That makes it one of the best air purifiers for smoke, which is especially appealing if you live in wildfire country. One of the Blue Pure 311 Auto’s biggest advantages is its cylindrical shape, which gives it 360-degree air intake. Most other models on the market can only pull in air from one direction, which limits their cleaning potential.
Getting this air purifier up and running is as easy as it gets. After taking it out of the box and plugging it in, tapping the top of the device will set it to auto mode, which detects the proper power level based on the particulates in your home. Tap it a few more times and you can cycle through the three different power modes as needed. When operating at full speed, the Blueair produced 55 decibels of sound, putting it right in line with every other model tested. At low speed, it’s whisper-quiet at around 25 decibels. The Blue Pure 311 Auto is rated for use in a 388-square-foot room. A typical bedroom is right around 200 square feet, so it should have no problem handling most areas of many homes.
Like any worthwhile air purifier, the Blue Pure 311 Auto uses an internal HEPA filter and an external pre-filter—which is actually the colorful fabric stretched around its base. The pre-filter is machine-washable and vacuum-safe, making routine maintenance much easier to deal with compared to every other air purifier we tested. Once you’ve removed the pre-filter, you can pull out the HEPA filter and toss in a new one. Blueair recommends doing this every six months if the Blue Pure 311 Auto is running continuously. If you forget, your air purifier will remind you with a blinking light.
HEPA filters cost about $35 if you’re signed up for a subscription, making your annual filter expenses just $70—one of the lowest prices among models tested.
One minor sticking point is the filter changes take a bit of time to get used to. Instead of simply unclipping a plastic screen, you’ll need to remove the pre-filter, which is held in place by elastic and a strip of Velcro. Removing the cylindrical pre-filter is easy enough, but trying to fit it back on the HEPA filter can be cumbersome. It’s a minor knock, especially since you technically only have to remove it twice a year, but it’s one of the only instances of putting form over function.
The EverestAir offers the best air-cleaning performance and brings a ton of futuristic features to your smart home.
Although the Levoit EverestAir carries a price tag double that of our top pick, it backs it up with tons of high-tech features you won’t find on other air purifiers. It also performed the best in our at-home stress test, clearing out a staggering 98.6% of smoke in just 30 minutes. It even managed to do so without being extremely noisy, maxing out at 57 decibels.
The first thing you’ll notice about the EverestAir is its size—clocking in at a gigantic 18.9 inches wide and 23.2 inches tall, the air purifier takes up a good amount of floor space. But unlike other products we tested, this one is designed for large spaces of up to 558 square feet. It’s also a great-looking product, with a modern design that makes its large footprint easier to deal with.
Setting up the EverestAir is straightforward, and using it is even easier due to its native support for Amazon Alexa and Google Assistant. Auto Mode will likely become your default setting, as it’s able to accurately scan the environment for debris using a three-channel laser dust sensor and toggle between its various power levels. If you’d rather not control the purifier with a voice assistant, you can adjust multiple settings from the top of the unit, including fan speed and timers, and there’s an easy-access button for Turbo Mode to quickly remove pollutants.
All these buttons are accompanied by a display that highlights the current air quality, although its measurements weren’t quite as accurate as our scientific particle counter. Filter changes are easy to perform (thanks to a simple latching mechanism that can be released to access the pre-filter, filter and an additional activated carbon filter), and Levoit recommends you change your HEPA filter every 12 to 15 months.
One of the unique, but useful, features of the air purifier is its adjustable vent angles. This allows you to alter the flow of the purified air, letting you angle it straight toward the ceiling or at a 45-degree angle to help it better circulate through your home. It also means you can place the unit underneath a counter or inside an alcove and still achieve impressive results.
It might look a bit cumbersome, but don’t let that fool you—this budget-minded air purifier punches well above its price tag.
The Coway Airmega 200M is an excellent air purifier for shoppers in the market for a lower-price product. Despite its relatively low price tag, it managed to perform admirably during our test, and nearly as well as our top pick with a 94.2% clearance rate. Its design isn’t as upscale as the EverestAir or Blue Pure 311 Auto—it looks more like a piece of industrial equipment than home decor—but that’s a minor knock for such great performance.
Like most air purifiers, the Airmega 200M is controlled by a panel of buttons on the top of the device. Fan speed, timers and filter reset buttons are all present, along with an air quality indicator that changes color based on the number of particulates in the room. Filter changes are impressively simple and lower-priced than the competition’s, and the purifier can save you even more money by automatically turning off after 30 minutes if it detects clean air.
The most intriguing button on the Airmega 200M is the Vital Ionizer, which the company says is to capture ultrafine airborne particles such as viruses and bacteria by creating an electrochemical reaction. Research on the efficacy of such a feature is mixed at best , and it’s nearly impossible to evaluate in an at-home test.
Coway says testing confirmed its air purifier can in fact capture 99.999% of ultrafine particles—although it’s unclear how much of that is due to the Vital Ionizer versus the standard HEPA filter. If you plan to use the Airmega 200M for an extended period of time, it might be best to leave this feature disabled, as some experts are wary of dangerous levels of ozone that may be produced by ionizing purification methods. (Pediatrician and allergist Dr. Zachary Rubin says: “I prefer HEPA air purifiers because they do the best job of improving air quality but do not have the potential risk of generating ozone that ionizer air purifiers can.”)
It doesn’t quite hit the highs of other air purifiers, but its easy-to-use design and impressive performance make it worth a closer look.
With a design that looks like a jet turbine, a fantastic user interface and a versatile smartphone app, the Levoit Core 400S checks all the right boxes. It couldn’t quite manage to hang with the best air purifiers in terms of air-clearing performance during our at-home testing, with a 93.8% clearance rate (falling behind the lower-price Coway Airmega 200M), but if you want a lower-price air purifier with great smart-home functionality, the Core 400S might be worth a closer look.
Much like our top pick, the Blue Pure 311 Auto, the Core 400S’s spherical layout allows it to pull in air from all directions for a symmetrical clean. The HEPA filter is also easy to access via a handle on the bottom of the device, with filter changes expected to cost $100 annually.
After setting up your Levoit account for the smartphone app and syncing with Amazon Alexa or Google Assistant, controlling the Core 400S is as simple as checking your Instagram feed. You’ll be able to quickly adjust its fan speed or check on its filter status through your smartphone, though if you’d rather not mess with an app or voice assistants, all the main controls are located on top of the unit as well. The touch-sensitive buttons are arranged in a circle around a central display that shows your current air quality, which complements the air purifier’s cylindrical design.
The Coway Airmega AP-1512HH Mighty is similar to the Coway Airmega 200M. It’s offered with a slightly higher price tag but was outperformed by its sibling during our stress test, as it only offered a 92% clearance rate. Many features are shared across the two devices—including the questionable ionizer—making it difficult to recommend over the lower-price Airmega 200M.
The Molekule Air Pro is the most deluxe air purifier to find its way onto our list of finalists, but its $1,000 price tag makes it a tough sell. It performed about as well as the Blueair Blue Pure 311 Auto that costs about a quarter of the price (a 95.4% clearance rate compared with the Blueair’s 95.1%), and it’s one of the few products on the market that’s gained FDA clearance as a 510(k) Class II medical device . So while its hefty price tag might not result in significantly improved smoke clearance, it could help eliminate bacteria and viruses floating around your home, and that may be worth the cost to some people.
Clorox might not be the first company that comes to mind when thinking of air purifiers, but its Large Room True HEPA , which is made by Hamilton Beach Brands , managed to catch our eye because of its lower price and well-known branding. Its performance fell behind those of most other air purifiers we tested (92.5% clearance rate), although its ease of use and streamlined design makes it a strong alternative. The Coway 200M carries a similar price tag and lower-price replacement filters, making it a better fit for most households.
Dyson makes a handful of air purifiers, many of which offer climate-control as well as air cleansing capabilities, placing them outside the scope of this guide. There are a few other reasons the Dyson Purifier Cool Autoreact TP7A didn’t make our list of finalists. Its high price tag places it at the top end of the market, and its lack of on-unit controls, smart home integration and a companion app are noticeable omissions for a premium air purifier. Stepping up to the Purifier Cool TP07 gives you voice and app control, but it costs at least $70 more than even our higher-end pick. Both are also designed to cool as they purify the air, which might not be ideal during cold winter months. A backflow option is available to mitigate their cooling capabilities, although it might be easier to opt for a traditional purifier than mess with various cooling settings.
I’ve been writing about consumer electronics for more than four years and previously worked in the biotechnology industry. I’ve worked in clean rooms (rooms designed to be virtually contaminant-free) equipped with advanced HEPA filtration systems producing monoclonal antibodies to treat cancer patients, and I have a background in biology and air quality from previous careers, along with a degree in biological science. I’ve also been a medical editor.
To learn more about air purifiers and air quality in general, I connected with three experts in the field. Zachary E. Rubin, M.D., a double board-certified pediatrician and allergist at Illinois’ Oak Brook Allergists ; Karen Bartlett, Ph.D., professor and graduate program director for the School of Population and Public Health at the University of British Columbia ; and Jose-Luis Jimenez, Ph.D., distinguished professor of chemistry for the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder . Their expertise helped create a list of criteria against which our air purifiers could be tested, as well as identify which features are crucial to a purifier’s performance.
With hundreds of air purifiers on the market, it can be challenging to whittle down your options. Our experts stressed the importance of picking a product that’s been rated for the size of your room. This comes in the form of a clean air delivery rate value given by the Association of Home Appliance Manufacturers . This offers a good starting point for your search. We stuck with products that were rated for at least 300 square feet—a size that should serve most rooms of your house with ease.
Beyond the CADR value, several other criteria were used to select our finalists.
With this list in hand, we selected several finalists for a rigorous at-home stress test. We introduced smoke to a 12-foot-by-12-foot room (with windows and doors closed and the HVAC system turned off) by lighting a large candle, and allowed the smoke to circulate until it was evenly distributed throughout the room. This produced close to three million airborne particulates per cubic foot—a number that bumped up against the upper threshold of our particle counter.
Fine Copper Mesh Fabric We recorded smoke measurements with the Temtop PMD331 Particle Counter before turning on each air purifier and enabling its most powerful fan speed. After 15 minutes, we took a final reading to determine the amount of smoke clearance. We also took a noise measurement to determine the purifier’s loudest operating volume. This entire process was then repeated to obtain a second measurement, and then we averaged the values. We also extensively tested the on-unit controls and other advertised features of each purifier to determine their value and ease of use.