The 6 best air purifiers that clear allergens, dust, and smoke fast

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The best air purifiers work their magic in the background of your life. You want to set them up, forget about them, and let them enhance your indoor air quality. We've come to view them as a household essential, whether you're trying to reduce exposure to viruses during flu season or sensitive to air pollutants like dust, pet dander, mold spores, and smoke.

We interviewed three experts and tested over 40 units to find the best air purifiers for allergies, smoke, and VOCs, focusing on HEPA-rated or carbon-filtered designs. Air purifiers use a fan to pull air through filters that traps pollutants and irritants, then releases cleaner air back into the room. Our top pick is the Coway Airmega AP-1521HH Mighty; it removed the most pollutants, allergens, and VOCs in our tests and operated quietly. For a budget option, consider the under $75 Lasko LP300 HEPA Tower Air Purifier. It has low filter replacement costs too, though it's most efficient for small rooms, like bedrooms.

Our top picks for air purifiers

Best overall: Coway Airmega AP-1521HH Mighty - See at Amazon

Best budget: Lasko LP300 HEPA Tower Air Purifier - See at Amazon

Quietist: Levoit 300S Air Purifier - See at Amazon

Best for large rooms: Honeywell PowerPlus HEPA Air Purifier - See at The Home Depot

Longest-lasting filter: Shark NeverChange Air Purifier Max - See at Amazon

Best for odors: Oransi TrueCarbon 200C Air Purifier - See at Walmart

Best overall

The Coway Airmega AP-1521HH Mighty air purifier outperformed other units. It was the fastest at removing air pollutants like dust, pollen, pet dander, and volatile organic compounds (VOCs). It's a excellent choice for allergy sufferers as it has a multi-filtration system: a washable pre-filter, a true HEPA filter to capture airborne particles like viruses, bacteria, and pollen, and an activated carbon filter that reduces cooking, smoke, and pet odors. It also features an ionizer; however, we don't recommend using the ionization function (see why in the FAQ). Fortunately, you can manually turn it off.

All controls and settings are made directly on the unit. This version is not WiFi equipped and it doesn't have a remote control, either. However, it's easy to set up and use. Even more important for the day-to-day, it runs quietly. I appreciated its eco-friendly design and Eco mode option. When this setting is selected, the air purifier's fan automatically stops to save energy after 30 minutes of no detected pollution, a feature that no doubt contributed to its ranking for lowest energy consumption among the units we tested.

The Coway displays air quality in real time. An indicator turns from red (unhealthy) to purple (moderate) to blue (good). It automatically adjusts the fan speed accordingly and can run on one-, four-, or eight-hour timers. I found its appearance unobtrusive, but some users may find the manufacturer's recommendation to place it on a slightly elevated surface, such as a table or stand, inconvenient. Overall, we think the Coway Airmega AP-1521HH Mighty air purifier is the best choice for medium-to-large rooms, especially for pet owners and allergy sufferers.

Annual filter replacements typically cost around $70. These include a True HEPA Filter and Activated Carbon Filter. The HEPA filter should last a year, while the carbon filter lasts six months. There is also a filter life indicator.

Read our full Coway AirMega AP-1512HH Mighty review.

Best budget

The Lasko LP300 HEPA Tower Air Purifier is the most affordable air purifier we recommend. It has the lowest filter replacement cost, and, at under 10 pounds, is easy to move from room to room. 

It performed just as well as models that cost three or four times as much. The Lasko air purifier quickly removed airborne dust and debris. With 30 minutes to spare in the testing period, our air quality monitor registered no particulate matter. Though its performance wasn't as impressive with VOCs, it did a good job keeping the levels in a safe range.

Setup was straightforward and took about five minutes. The Lasko's light weight makes it easy to move around, so you can take it with you from room to room, which you may need to do since its low CADR makes it better suited for small rooms. If you need more oomph, consider the LP450, which is only $16 more and covers twice as much space.

It's a bit loud and uses a lot of power. The Lasko was one of the few units we tested that was louder than ambient sound levels, even when on low. At 45.6 dB on low, it was a little bit louder than a typical library. On high, it was only 51.6 dB. It also uses a lot of power. This is likely due to its lack of an auto mode that adjusts with the air quality, which is another negative.

Filter replacements are affordable too, just $25 for an annual supply.

Quietist

The Levoit 300S Air Purifier is an excellent option for bedrooms and other small rooms thanks to its quiet operation and compact design. It has a three layer filtration system. The pre-filter captures larger debris, including hair and pet dander; the true HEPA filter collects smaller airborne particles; and the carbon filter helps reduce VOCs and odors in the air while operating at an ambient level of noise.

It was among the best at removing VOCs. The purifier also did well with particulate matter, removing virtually all (99.2%) of it from the air during the testing period.

It's pretty quiet. At low speed, it was no louder than ambient noise, making it well-suited for bedrooms. The noise level at high fan speed was average, a little louder than in a quiet office, but not disruptive at all.

The setup was a snap and it has smart features. I had the unit up and running in under five minutes and connected to the VeSync app (available for iOS and Android) in another five. The Levoit 300S is the most affordable WiFi-connected air purifier I've tested, and the smart functions work well. I could easily monitor and schedule it from anywhere, and the air quality readings were almost identical to the readings on our testing monitor.

The Levoit 300S is Energy Star-certified. The auto mode that adjusts the fan speed based on the air quality. It proved to be one of the lowest energy consumers we tested.

Maintenance is minimal. Vacuum the pre-filter once or twice a month and replace the filter every 6 to 8 months when the indicator light turns on. Filters are affordable and widely available, costing about $55 a year.

Best for large rooms

The Honeywell PowerPlus HEPA Air Purifier (model number HPA3300) was the top performer for large rooms. An hour and fifteen minutes into our test, it had removed 99% of the particulate matter and lowered the VOC levels to nearly zero. While it hasn't specifically been certified by the Asthma and Allergy Foundation (AAFA), these numbers suggest this is an excellent air purifier for allergy sufferers and those sensitive to other irritants.

The setup was quick and intuitive. It simply required removal from the package before plugging it in. And there's little maintenance. Just wipe the unit down with a dry cloth every three months. Two distinct filter indicator lights make filter replacement a no-brainer: the HEPA filter is changed once a year, and the prefilter requires replacement every four months.

The HPA3300 isn't without its drawbacks. First, it's one of the loudest models we tested. When on low fan speed, it's no louder than the surrounding noise, but on high, it registered 64 decibels (dB), which is about as loud as a normal conversation. At over 20 pounds, it isn't as portable, though it does have a handle to help with transport.

That said, it's similar to most models in power use and filter replacement costs (about $100 each year), and we think its performance makes it the best air purifier for large rooms, especially for allergy sufferers.

Read our full review of the Honeywell PowerPlus Air Purifier.

Longest-lasting filter

Shark takes long-lasting filters to the next level. Most filters need to be replaced quarterly, but the Shark NeverChange Air Purifier Max can last up to five years before you need to replace the filter, and when you do, that filter costs $80. This is significant because some filters cost that much just to run annually. The size of the room (up to 1,400 square feet) and the amount of time you run the unit will ultimately determine how much life you get out of the filter, but according to Shark, the five-year number is based on running the air purifier in a 300-square-foot room at the highest speed for 12 hours a day.

It's fast-acting and quiet. From a performance perspective, the Shark took less than 15 minutes to reduce the amount of particles from incense smoke in a 200-square-foot room by 90%. It's also one of the quietest models, just behind the Blueair: an unobtrusive 46 decibels when running on high, and ambient at other levels. 

All controls are handled directly on the unit. The Shark NeverChange Air Purifier Max is not WiFi-equipped, but the LCD screen can show the clean air percentage, the cleanliness level of the pre-filters, or real-time particle count. You can also adjust the fan speed or let it run on Auto. It has one of the lowest energy uses, at about .08 kwh a day. 

Despite minimal upkeep costs, it's not completely maintenance-free. The two pre-filters, which catch larger particles like pet hair, need to be wiped or vacuumed periodically, but these are permanent as opposed to requiring replacements. The display screen shows a filter-life percentage and will alert you when the filters need cleaning. 

The Max is Shark's largest size. This also makes it a bit bulky if you plan to move it around from room to room. Shark also offers a smaller version rated for rooms up to 650 square feet and a compact version for rooms up to 250 square feet, and it comes in fashion colors like lavender or light green. 

Read our full Shark NeverChange Air Purifier Max review. 

Best for odors

The Oransi TrueCarbon 200C Air Purifier is our top choice for removing odors like cigarette smoke, paint fumes, and diaper pail smells. It's compact, light, and easy to move; it can reside on the floor or tabletop. It's ready to go out of the box, and includes a remote to manually adjust the fan speed.

The Oransi is straightforward to use. It's no-frills with no air quality sensor, app, or WiFi connection feature to navigate. In addition to doing a nice job of clearing out VOCs and particle matter in our incense tests, this air purifier, which uses a 3.2-pound carbon filter — which the company claims is thicker and more efficient than competitors— eliminated every hint of odor from the small patio where my cats' litter boxes are stationed. While this model did a good job of clearing VOCs during our tests, carbon filtration is not engineered to filter pollen, dust, or other particulate matter.

One drawback is the noise level. Even at the lowest setting, the Oransi is loud. Our sound meter registered 46 dB, which is 21 dB louder than the quietest model we tested. Another con is that this model doesn't have an auto mode. That means you have to use your judgment to choose the setting (from one to ten) based on the severity of the odor.

If you're looking to eliminate odors in small-to-medium-sized rooms, the Oransi TrueCarbon 200C Air Purifier is a great option. However, filter replacements, which need to be replaced one to two times a year, are pricier than competitors.

What else we tested

Over the last few years, our product testing experts have examined nearly 40 air purifiers, and there are several that we almost included in our guide that are still worth considering:

Other air purifiers we recommend

Under $250

Levoit Vital 200S Smart Air Purifier: This budget-friendly air purifier is low maintenance, and filter replacements are more affordable than other models we tested. With auto mode and a smart app, you can control the settings and monitor your air quality from anywhere. It's a solid option and covers a larger area than the Levoit Core, our pick for small spaces.

Brondell Horizon O2+: For the price, this Brondell air purifier did an outstanding job, and I'd recommend it if our top budget pick isn't available. It was one of the top removers of particulate matter in our tests and was easy to maintain and clean. The biggest negative is that it doesn't have an auto mode that adjusts the fan speed based on air quality. This would have been nice since it consumes a lot of power.

Honeywell HPA 5200 (large rooms): This model performed well and did a decent job of clearing smoke and other particulate matter. However, it's heavier, bulkier, less energy efficient, and louder than other models that performed as well.

Instant Air Purifier 300: From the makers of Instant Pot, this air purifier was one of the top removers of VOCs, didn't use much power, and was easy to clean and maintain. Yet it was one of the worst at removing particulate matter, and it operates loudly.

PuroAir 240 Air Purifier: This value-priced air purifier is compact and tabletop-sized and features a built-in air quality indicator. It did an average job of getting rid of particles but struggled to decrease VOCs. It uses more energy than others, and the annual filter replacement cost can stretch to over $150.

Winix T810 Air Purifier: This smart air purifier is whisper-quiet on its lowest setting and can purify rooms up to 400 square feet nearly five times in an hour, but it struggles to lower VOCs. It also features Plasmawave technology, which is technically an ionizer, but you can turn that feature off and operate it without it.

Under $450

Blueair Blue Pure 211+ Auto: This is the updated version of the Blueair Blue Pure 211+, a top pick in a previous version of this guide. The main addition is an auto mode, which adjusts the filtering speed and intensity based on the air quality. We found it did a good job of filtering the air while using minimal electricity, but it was loud, and filters are expensive.

Coway Airmega 250: Another great option we tested from Coway. The 250 was one of the best removers of particulate matter. It also used minimal electricity, thanks to the fan that adjusts based on the air quality. However, it didn't perform well at removing VOCs from the air.

Dreo Air Purifier Tower Fan: This air purifier and fan combo is a fraction of the cost of the dual-function Dyson fan combos and does a good job of purifying the air, too. Its breezy and powerful fan modes can work in tandem or separately across 12 speeds. Unfortunately, replacement filters seem to be in limited supply.

Mila: Mila is a mid-range smart air purifier with a variety of filter options, depending on the air quality issue you want to address. I tested the heavy-duty Overreactor, a hospital-grade H14 HEPA filter, and the Basic Breather. The Overreactor was in the middle of the pack in our air purifying tests. The Basic Breather was outstanding at removing particulate matter. But both operated loudly, and there wasn't anything else that made them stand out.

Over $450

Alen Breathesmart 45i: This Alen air purifier relies on a medical-grade H13 true HEPA filter, which did an outstanding job of removing particulate matter from our test room. This model is also easy to set up, transport, and maintain. However, filter replacement will set you back about $140 per year. 

Coway Airmega 400S: Our previous pick for the best smart air purifier, the Coway Airmega 400S is an attractive unit that barely makes any sound and adjusts the fan speed based on the air pollution level, which lends itself to low energy use. However, it performed was just average in our purifying tests and its smart features aren't very robust.

RabbitAir MinusA2: If we had a "most visually appealing" category, this model would win. We weren't particularly impressed with how well it cleaned the air. However, it was easy to set up and maintain, and the filter replacement costs are reasonable.

Air purifiers we don't recommend

Dyson HP09: As a space heater, The HP09 does an outstanding job of heating and cooling rooms up to 800 square feet in size. The only problem is that it was one of the worst performers in our air purifying tests.

Honeywell Insight HPA5300B: I like the look of this air purifier, and it's easy to maintain and has widely-available filters. However, it used a lot of electricity and is loud on high speed. Plus, its performance in the air purifying tests was unimpressive.

EnviroKlenz Air System Plus: This is the heaviest and least visually appealing purifier we tested. It's designed to take a beating and is used by the US Navy. However, it had the highest VOC reading at the end. It doesn't have an auto mode, uses the most electricity, and has the highest filter costs of the bunch.

IQAir Atem: We were hoping this would be a good compact option, but it performed poorly in the air purifying tests and has high upfront and filter costs. 

Molekule Air Pro: With its sleek design and hefty price tag, we expected more from this model. However, the Winix T810 models outperformed the Molekule in our tests, and at a fraction of the price. When poor air quality caused the air purifier to kick into the highest setting, it was noticeably louder, too.

PhoneSoap AirSoap: The biggest reason the AirSoap isn't in our guide is because it relies on ionization to clean the air, and there is no way to turn it off. In fact, we don't recommend ionizing air purifiers for most people. The benefits of ionization are questionable, and there's a risk of negative health issues due to the low levels of ozone the AirSoap produces.

What to look for in an air purifier

With so many options available, choosing the best air purifier for your needs can be overwhelming. To help narrow down the options, consider these guidelines from the Environmental Protection Agency (EPA):

• Room size: Air purifiers are designed for specific room sizes, typically measured in square feet, so choose an air purifier that can effectively cover the space you plan to use it in. Before making a purchase, check the manufacturer's guidelines on the maximum room size each unit can handle. A unit that is too small will not clean the air effectively, while an excessively large one may be unnecessarily expensive and inefficient.
• CADR: CADR or Clean Air Delivery Rate measures the volume of filtered air that the air purifier delivers. In other words, it indicates how quickly it can remove pollutants like dust, pollen, and smoke. A higher CADR rating signifies better performance, but matching the room size in square footage is most important.
• ENERGY STAR Certification: ENERGY STAR certification indicates that an air purifier meets energy efficiency guidelines set by the EPA. Choosing an ENERGY STAR-certified model, designed to use less energy while effectively cleaning the air, can help reduce your energy footprint without sacrificing performance.
• HEPA filtration: High-efficiency Particle Air (HEPA) filters most effectively capture airborne particles. A true HEPA filter can trap at least 99.97% of particles that are 0.3 microns in size, including dust, pollen, mold spores, and pet dander. Choosing a model with a genuine HEPA filter provides the best air-cleaning performance. Models with a pre-filter trap larger particles, and carbon filters assist with odors.
• Filter replacement costs: Ongoing maintenance costs, including filter replacements, can add up over time, so consider how frequently the air filters need to be replaced. That way, you can choose a model that fits your budget in the short and long term.
• Avoid ozone-emitting units: Some air purifiers, particularly those that use ionization technology, can produce ozone as a byproduct. Ozone can be harmful to health, particularly for people with respiratory issues, and the EPA advises against ozone-producing air purifiers. Instead, choose an air purifier that's certified by the California Air Resources Board (CARB) or that's been tested to ensure it does not emit ozone.

How we test air purifiers

James has been reviewing heating, cooling, and air-quality devices for the past three years. Heidi lives with pets and allergies and has come to rely on air purifiers to keep symptoms at bay. For this guide, they tested about 40 air purifiers for at least one week each and consulted with Ravi Pandey, MD, an internal medicine specialist based in South Florida; Junfeng Zhang, PhD, professor of global and environmental health at Duke University; and Bryan Buckley, the brand manager for One Hour Heating & Air Conditioning.

Based on research and interviews with experts, the most important features to consider when shopping for an air purifier are its ability to remove irritants from the air, long-term costs, and ease of use.

Here are the main ways we test each model:

Purifying abilities: We burned incense in a 200-square-foot room with the windows and doors closed and used an air-quality monitor to take measurements of the volatile organic compounds (VOCs) and particulate matter in the air every 15 minutes. After the incense burned for 15 minutes, we turned on the air purifier's auto mode, which adjusts the fan speed based on the air quality. If it didn't have an auto mode, we used the highest setting. We looked at both the percentage removed and the amount of VOCs and particulate matter left after two hours. For context, all of the recommended room sizes in our guide are calculated assuming an eight-foot ceiling and four air changes per hour (ACPH).

Setup: We timed how long it took to set up the air purifier from opening the box until the unit was running. This includes connecting to an app when applicable. We'll note any unusual or confusing steps. Most models only required removing the packaging and plugging in the unit. This generally took five minutes or less.

Portability: We moved the air purifiers around the house, noting how easy they were to carry. A model that weighed more than 20 pounds or was hard to move physically lost points. Most units were easy to move and featured handles.

Long-term costs: Electricity and filter replacement are the biggest long-term costs, which can often outpace the upfront costs. We calculated annual filter costs and whether they're widely available and not just on the manufacturer's website, which can make it hard to price shop. We measured the power consumption of each unit over the course of 24 hours with a smart plug on the same setting used for the purifying tests.

Noise: An air purifier's operation should not interfere with hearing the TV, sleeping, or having a conversation. To test this, we used a sound meter to measure the air purifiers on their highest and lowest settings from four feet away. On low, most units were indistinguishable from ambient noise. 

Maintenance: We cleaned each air purifier per the manufacturer's recommendations and noted how easy each model was to clean. We also noted whether there were indicators to let us know when to clean or replace the filter.

Air purifier FAQs

Why do I need an air purifier? 

An air purifier cleans odors, pollen, pet dander, and more from indoor air. According to the EPA, units with HEPA filters can improve symptoms of COPD and asthma sufferers and effectively remove ash and smoke particles.

What do air purifiers remove from the air?

The type of filter a purifier has determines what pollutants it can remove. HEPA filters are popular because they can remove smoke, pollen, bacteria, pet dander, dust, mold, and other particulate matter of 0.3 to 10 microns. Activated carbon filters can remove VOCs and other gases.

What does HEPA mean?

HEPA is an acronym for "high-efficiency particulate air." The EPA defines a true HEPA filter as a filter that captures at least 99.97% of airborne particles that are 0.3 microns in diameter. This includes bacteria, dust, pollen, and mold.

What's the difference between true HEPA and HEPA-type filters?

True HEPA filters capture 99.97% of airborne particles that are 0.3 microns in diameter. According to the EPA, true HEPA filters can more easily catch particles larger or smaller than 0.3 microns. There's no standard for HEPA-type filters.

Can HEPA or H13 purifiers capture viruses, including the coronavirus?

Ravi Pandey, MD, a specialist in internal medicine in Florida, said HEPA air purifiers wouldn't eliminate the coronavirus. Still, they help, especially when used with mask-wearing, hand washing, and social distancing.

What can you do to get the most out of your air purifier?

Bryan Buckley, the brand manager for One Hour Heating & Air Conditioning, suggested always keeping your air purifier running in one spot. He added that you need continuous air purification to clean the air and maintain good air quality levels. Also, make sure filters are replaced on a regular schedule as a dirty filter can make your air purifier less effective.

Where are the best spots to place an air purifier? 

Air purifiers are best in high-traffic areas, such as your kitchen, living room, or bedroom. A purifier is also excellent at removing smoke from cooking. Buckley said you should position the unit to blow clean air where people gather and close your windows during use.

How often should you change the filter?

It varies. Manufacturer guidelines range from every 3 months to 5 years. We note the replacement schedule for the models in our guide and anticipated annual filter costs. Follow the schedule in your air purifier's user manual for optimal efficiency and performance.

Can plants help clean indoor air?

Probably not. The Journal of Exposure Science & Environmental Epidemiology published a study in 2019 showing that indoor vegetation did not remove air pollutants.

How can you keep your air clean if you don't have an air purifier?

You can clean the air without a purifier by cleaning regularly, ventilating with fans, and storing chemicals outside of your house. Junfeng Zhang, PhD, professor of global and environmental health at Duke University, recommended wearing N95 masks in polluted areas.

Are air purifiers worth it?

If you cannot take steps to improve your indoor air quality by other means or the pollutants still seem to stick around, an air purifier is an intelligent choice. Even the worst air purifiers we tested improved indoor air quality.

Are ionizing air purifiers safe?

Ionizers can generate ozone, a lung irritant. Enesta Jones, an EPA spokesperson, said even low amounts of ozone could cause shortness of breath, chest pain, throat irritation, and coughing. Because of this, we don't recommend any air purifiers that don't let you turn off the ionizing function.

What about air purifiers that combine with humidifiers?

The best humidifiers serve a very different purpose, to add moisture to the air while air purifiers remove pollutants. The experts we consulted still recommend keeping the devices separate, citing concerns over different maintenance needs and the air could get too damp, which leads to mold and mildew growth. Combining does take up less space and can minimize the risk of fungus growth. If you must, the choices are few and far between — and expensive — with the Dyson Purifier Humidify+Cool PH2 De-NOx, as and the BlueAir 2-in-1 Purify + Humidify, neither of which we have tested.

Can air purifiers help with wildfire smoke?

Yes. Zhang recommended air purifiers with HEPA filters to improve indoor air quality in areas affected by wildfires. Air purifiers will be most effective if you keep windows and doors closed. Also, have purifiers in each room rather than moving one from room to room.

Air purifier terms to know

In this guide, we throw around a lot of terms you may not be familiar with. Here are a few definitions of terms and acronyms that are commonly used when talking about air purifiers:

CADR: Clean air delivery rate. Typically measured in cubic feet per minute or cubic meters per hour, the CADR tells you how much air an air purifier can clean. Some companies will have different CADR ratings for smoke, dust, and pollen.

cfm: Cubic feet per minute. This is the most common unit of measurement used to express how much air an air purifier can clean or process every minute.

HEPA: High-efficiency particulate air. True HEPA or HEPA-type filters are generally considered to be the gold standard in the industry.

VOCs: Volatile organic compounds. These compounds have low water solubility and high vapor pressure. They are commonly produced in the manufacturing of refrigerants, pharmaceuticals, and paints and are often found in paints, craft materials, adhesives, markers, furniture, pesticides, cleaning supplies, and more.