According to the Environmental Protection Agency, research has shown that the air inside our homes is often even more polluted than the air we breathe outside, which can contribute to allergies, aggravate asthma, and make you more susceptible to illness. The best air purifiers can help minimize these symptoms by trapping airborne particles and removing them from the air you breathe. “Good indoor air quality is important for everyone, especially for those living with asthma and allergies,” says Kenneth Mendez, President and Chief Executive Officer of the Asthma and Allergy Foundation of America (AAFA). “Indoor air can be full of asthma and allergy triggers including dust mites, pet dander, smoke, volatile organic compounds (VOCs), odors, and even pollen and air pollution from outside. … Air purifiers can improve your home’s indoor air quality. " We put 38 of the best air purifiers to the test in our lab in Des Moines, Iowa, exposing them to common household allergens and evaluating them based on their noise level, ease of use, effectiveness, and design. Our team of experts also noted any additional features the air purifiers offered, the surface area they were able to filter, and their overall value compared to the price. Finally, we sent the best air purifiers from our lab tests home with our experts, where they used the devices in their own homes for an entire month. After spending three full days testing in our lab, we concluded that the Levoit Core 400S Smart True HEPA Air Purifier is the best air purifier out of all the models we tested. Our testers found that it had a wide range of helpful features to view and improve the air quality of your space while remaining quiet and easy to use. Keep reading to learn more about the other best air purifiers we tested. Keep in Mind: It’s less effective in rooms larger than 900 square feet. Understanding the air quality in your home can feel like a confusing and overwhelming topic, but the Levoit Core 400S Smart True HEPA air purifier makes it easy to understand. This lightweight model works in rooms up to 990 square feet, and it uses three different filters to remove dust, bacteria, pollen, smoke, and more from your home. During testing, we found that it was extremely effective against particles, VOCs (harmful gasses), and smoke in the air when running on both its low and high settings. When running for just 10 minutes at a time, we found that the Levoit Core 400S Air Purifier not only detected poor air quality levels, but it also made the air even cleaner than it had been prior to the test. Our testers described setting up the Levoit Core’s integrated app as “very user-friendly.” You’ll be able to easily check the room’s air quality within the app, which shows a specific PM 2.5 (particulate matter) rating and indicates the air as “very good,” “good,” “moderate,” and “bad.” You’ll also be able to program the purifier to use different fan speeds and modes at different times of the day, schedule it to shut off at certain times, and more. We liked that the Levoit Core’s display on the device is equally easy to read, so you don’t have to connect it to an app in order to use this machine. It’s also Energy Star certified, which means it requires less energy to operate than competing models. While this air purifier is advertised to work well in rooms up to 990 square feet, it will take more time for the device to improve the air quality in larger rooms. We recommend purchasing multiple air purifiers if you need to use it in a space larger than 900 square feet for the best results. “This air purifier has definitely helped with the air quality in my apartment,” our tester said. “Before, we had a damp smell in our entryway, and now, it seems to have disappeared! I’ve moved the air purifier from room to room, and I can tell a difference when it’s on in a room versus when it’s not. I feel like I’m breathing clean air!” Price at time of publish: $220 Product Details: Room Size: Up to 990 square feet | CADR Rating: 260 CFM / 442 m³/h | Noise Level: 52 decibels | Dimensions: 10.8 x 10.8 x 20.5 inches | VOC Filtration: Yes Keep in Mind: It doesn’t offer app connection. No matter how much air pollution your home is exposed to, you don’t necessarily have to spend hundreds of dollars to keep it clean. We were extremely impressed by the capabilities of the Aroeve air purifier, which filtered contaminants out of the air during our tests just as effectively as models costing hundreds more. This compact air purifier is only 13.5 inches long by 7.5 inches wide, but according to the manufacturer, it’s powerful enough to work in rooms up to 1,095 square feet. It’s equipped with a H13 True HEPA filter, so it can capture particles 0.3 microns in size with 99.9% accuracy, including dander, dust, airborne contaminants, and more. We found that it reduced PM 2.5 levels in our test environment from a hazardous level to clean breathing air in 10 minutes—slightly slower than the more expensive models we tested but not enough to make a big impact when buying. Over the course of months of use, our tester appreciates how efficiently it works in her kitchen. When she cooks, she moves the air purifier from her bedroom to her kitchen and finds that it eliminates smoke and odors faster than opening a window. All of its settings are conveniently located at the top of the machine, including two fan speeds, an auto mode, nighttime mode, and an 8-hour, 10-hour, and 12-hour timer. The circular display will also change colors to indicate the PM 2.5 levels from blue (good) to yellow (moderate) to red (poor), so you can assess your room’s air quality at a glance. It also offers a UV setting that the manufacturer claims purifies the air more thoroughly than other models—though we noticed no difference during our tests. Even when operating on the highest setting, the Aroeve air purifier’s noise remained unobtrusive at just 22 decibels—approximately the same noise level as a shower running. When operating on sleep mode, our testers said it was just 42 decibels, which is about the same noise level as a quiet office. If you want more detailed information about your home’s air quality or a specific PM 2.5 reading, this air purifier may not be the right choice for you. It doesn’t have a way to display an exact air quality reading, and it doesn’t offer app connection for in-depth insights. The only way you can assess your home’s air quality levels is by looking at the color-changing display. When the time comes to clean it, our tester found it to be a pain-free experience—a little bit of vacuuming was all it took to get it going again. Price at time of publish: $130 Product Details: Room Size: Up to 1,095 square feet | CADR Rating: 300+ (m³/h) | Noise Level: 22 decibels | Dimensions: 13.5 x 7.5 x 17.25 inches | VOC Filtration: No Keep in Mind: It isn’t as effective in larger rooms, like your living room or kitchen. Purchasing an air purifier can be a great way to help manage seasonal allergies since the purifier will remove pollen from the air you’re breathing. Our tester noticed that she didn’t have a runny or stuffy nose after using this air purifier in her home for a few months. The Dyson Purifier Cool was one of the best air purifiers we tested, significantly decreasing the number of particles in the air in just five minutes. After adding smoke and pet hair to the room, this model reduced the PM 2.5 (particulate matter) levels from 999.9 to 115.2 after five minutes and to just 8.0 after 10 minutes. The replaceable HEPA filter has activated carbon in it, which helps to capture gasses and odors, and it’s capable of trapping particles like pollen, dander, and dust as small as 0.3 microns. Our tester noticed the air purifier sensed when she was painting her nails, and she was pleasantly surprised by how intuitive it is. Its 360 degree filtration system allows it to pull in air from all sides at once, so it cycles through the air more quickly than other models. You’ll be able to see the room’s air quality in real-time on the LCD screen at the front of the machine and read a detailed report on the Dyson Link app. Since it tracks your air quality over time, you can see a chart of how your room’s air quality has changed to help you understand potential causes. We also liked that the display shows the room’s temperature and moisture levels in addition to the air quality. Our tester raved about how quiet this machine is, even at its highest fan speed. During testing, the Dyson Purifier Cool did not make noises above 64 decibels—similar to the sound of a fan running on low. This means you’ll be able to run it in the middle of the night without worrying about the noise disturbing you. Plus, the air purifier’s night mode allows the unit to run at its quietest settings and even dims the screen so the light won’t wake you. This air purifier also has an Energy Star certification, so you don’t have to worry about your energy bill spiking every time your device is running. It even includes a built-in fan, helping to circulate air throughout the room and keep you cool. According to Energy Star, the Dyson Purifier Cool works best in rooms around 125 square feet, which is about the size of the average bedroom. This means it’s less suitable for larger areas of your home, like your living room or kitchen. Price at time of publish: $539 Product Details: Room Size: Up to 800 square feet | CADR: Not listed | Noise Level: 64 decibels | Dimensions: 4.72 x 8 x 41 inches | VOC Filtration: Yes Keep in Mind: The app was more difficult to set up than other models we tested. No matter how much cleaning you do, there’s likely a lot of airborne dust particles floating around your home. However, the Coway Airmega 400S air purifier can help to remove that dust from your air by trapping it in the HEPA filter so you’re not breathing it in all day. It works in rooms up to 1,560 square feet, cycling through all of the air at least two times every hour to remove dust, dander, airborne contaminants, and more. Our testers found that this air purifier quickly reduced the PM 2.5 levels in the room we tested it in, decreasing the rating from “hazardous” levels to harmless in less than 10 minutes. Because it’s made for large spaces, it’s a big purifier—something that surprised testers—so if you’ve got limited floor space, this is probably not the model for you. You’ll be able to connect the Coway Airmega 400S to an app, which allows you to see more detailed insights about your home’s air quality, access reports over different periods of time, manage the device’s settings, and more. The addition of the app was a feature that our testers enjoyed when they used the purifier at home, especially the ability to monitor air quality. Unfortunately, our testers had trouble finding the app on their phones since this device’s manual didn’t include a QR code, and it took several minutes to get everything connected. However, you can also use the Coway Airmega air purifier without the app by using the buttons on top of the machine. When on smart mode, this air purifier will automatically change its settings to best suit the room’s air quality and lighting conditions. You can also set a timer, change fan speed, and easily see when the device needs a filter replacement. Price at time of publish: $651 Product Details: Room Size: Up to 1,560 square feet | CADR: 328 (smoke), 328 (dust), 400 (pollen) | Noise Level: Between 22 and 52 decibels | Dimensions: 14.8 x 14.8 x 22.8 inches | VOC Filtration: Yes Keep in Mind: This device is louder than other air purifiers we tested when running at its highest fan speed. Getting rid of smoke from your home can be a difficult task, whether you’re near someone who smokes cigarettes, you live in an area impacted by wildfires, or your home is exposed to smoke from another source. Since simply putting a wall between you and the source of smoke isn’t enough to stop harmful particles from getting into your airways, purchasing an air purifier can be one helpful solution. During our tests, the Bissell Air400 Professional air purifier performed the best against smoke out of all the devices we tried. After adding smoke to an enclosed space with the air purifier, the device accurately registered a hazardous level of PM 2.5 on its screen, but after just five minutes it reduced the levels by more than 990 points to a healthy level again. This is partially due to the device’s three stages of filtration, which include a pre-filter, an activated carbon filter, and a HEPA filter. While the HEPA filter captures particles like pollen, smoke, and dander, the carbon filter is designed to capture gasses and odors in your home. According to the manufacturer, this device can cycle through the air in a 783-square-foot room three times in a single hour. Our tester, who already owns several other air purifiers for her home, said she loved using the Bissell Air400 to help with cooking smells and managing pet hair. She doesn’t have a range hood in her kitchen, so she uses the air purifier when she is cooking to help reduce the smoke in the air. The digital display provides an exact reading of your home’s current PM 2.5 levels, and the outside of the display changes colors from green to yellow to red to indicate air quality. This makes it super easy to know how clean your air is in just a glance. Our tester noted the air purifier is effective at detecting when there are changes in air quality, like when she cooks or lights a candle. It’s also Energy Star certified, so it runs more efficiently than other units. On low mode, we found that the Bissell Air400 Professional air purifier is whisper-quiet at just 40 decibels, though it can be a bit noisy when run on high (80 decibels). However, our tester reported that, even on low mode, it drastically reduced PM 2.5 levels in a room in under 10 minutes. Price at time of publish: $360 Product Details: Room Size: Up to 485 square feet | CADR: 353 (pollen), 319 (dust), 313 (smoke) | Noise Level: 80 decibels | Dimensions: 12.20 x 18.9 x 27.24 inches | VOC Filtration: Yes Keep in Mind: It took our testers awhile to assemble it upon unboxing. If you own pets, you already know how much work it takes to keep a tidy home with a furry friend or two sharing your space. Since pet hair and dander can have a negative impact on your air quality, a reliable purifier can capture and remove allergens from the air you breathe. We chose the Rabbit Air MinusA2 as the best air purifier for pets, because it removed dander and allergens from our test space faster than any other model. When set to its highest setting and placed in our test environment with pet hair and smoke, this powerful yet slim air purifier reduced PM 2.5 levels from 999.9 (hazardous) to 1.1 in just five minutes. Our testers found that the Rabbit Air2 purifier made it very easy to read and understand the air quality of the room, changing colors to indicate quality. The display also has different settings for odors, pollen, quiet operation, and even a light sensor that automatically dims the display when the room is dark. You can also download an app to find out more detailed information about your home’s air quality, change the settings, adjust the device’s mood light, and more. It comes with a mounting kit, so you can hang it on your wall if you lack floor space. This air purifier is also Energy Star certified, so it won’t take up a ton of electricity to run it. The Rabbit Air2 purifier has six built-in filters, including two HEPA filters to remove 99.9% of particles 0.3 microns in size and an activated carbon filter for trapping airborne contaminants and household allergens. It’s designed to work in spaces up to 815 square feet, making it versatile enough to work efficiently in most bedrooms, living rooms, and home offices. During testing, it took our experts a little more time to set up this device compared to other air purifiers we tested. Since all the pieces were individually packaged, we had to assemble it ourselves using the included instructions, which took some work to decode. However, given how quickly it purified the air during our tests, we still found it to be well worth the money. “I like the design, it’s sleek and modern, and while it’s wide, it’s not very deep so it doesn’t take up too much space,” our tester said. “When set to auto mode, it changes settings based on air quality in the room. Generally, it runs on low, which means it’s maintaining the quality air in the room all the time. I used it in my bedroom when I was sick, and I noticed that once I was feeling better, the air purifier has been running a lot less!” Price at time of publish: $620 Product Details: Room Size: Up to 815 square feet | CADR: 200 (Pollen), 193 (dust), 180 (smoke) | Noise Level: Between 25.6 and 51.3 decibels | Dimensions: 20 x 21 x 7 inches | VOC Filtration: Yes Keep in Mind: This unit is not Energy Star certified. Instead of purchasing multiple appliances to keep your home clean, cool, and comfortable, the Dyson Purifier Humidify+Cool Formaldehyde is a space-saving, three-in-one option. In addition to being a powerful air purifier, it also has a built-in humidifier and a fan that oscillates to provide cooling to the whole room. When placed in an enclosed space with smoke and pet hair, the Dyson Purifier Humidify+Cool quickly filtered out airborne particles and reduced the PM 2.5 levels to a healthy rating in just five minutes. Our testers loved how easy the air purifier was to operate, thanks to a sleek control panel on the front. Its sensors continuously analyze the air and diagnose pollutants in the room, then display live PM 2.5 levels on the screen so you can monitor your air quality in real time. The HEPA filter will capture 99.97% of airborne particles from the air, then seals these particles away so they can’t escape out of the device. Our tester reported that after consistently using this air purifier, she experienced fewer allergy symptoms than usual. For even more detailed information and setting control, you can connect the device to the Dyson Link app or even pair it with your Alexa, Siri, or Google Assistant. If you want to use the humidifier and purifier features without the cold breeze, simply turn on the backwards airflow, which diverts the air through the back of the fan instead of the front. Our tester appreciates how versatile the settings are, and likes being able to change the speed and direction of the fan. It also has a handy night mode for quiet operation while you’re sleeping and a remote control that allows you to change settings from across the room. Keep in mind that, while this air purifier has tons of helpful features that make it well worth the price, it’s not Energy Star certified. This means it will use more energy to operate than other models with an Energy Star certification. Price at time of publish: $919 Product Details: Room Size: Up to 400 square feet | CADR: Not listed | Noise Level: Not listed | Dimensions: 36.33 x 11.02 x 12.23 inches | VOC Filtration: Yes Keep in Mind: Its boxy shape takes up a lot of space in your home. If your home features an open-concept design, it can be tricky to find an air purifier that can efficiently filter through all of the air inside the room. That’s why we liked the Winix 9800 Large Room True HEPA air purifier. It’s designed to remove particles from the air in rooms as large as 2,420 square feet in just one hour. One of our testers’ favorite aspects of this device is the detailed information it gathers and displays within the connected app. You’ll be able to see the specific air quality at any time, assess how your room’s air has improved or declined across several months, set up times for the purifier to run, and more. During testing, it quickly removed dust, dander, and smoke particles from the air in as little as five minutes, reducing the PM 2.5 levels in our test environment from 800 to 6.5. Our experts reported that it didn’t suck up any of the pet hair we’d strewn about inside the room (though other air purifiers did), but this didn’t seem to impact its ability to clean the air and trap airborne particles. It has a washable pre-filter, a True HEPA filter, and an activated carbon filter to reduce odors from cooking, pets, and more. You can change settings either in the app or directly on the machine, using clearly marked buttons to increase fan speed, connect to WiFi, view the air quality, and turn on night mode. The unit is also certified by the Association of Home Appliance Manufacturers and by Energy Star, so it’s guaranteed to work in large rooms without using up a ton of electricity. Since it works in such large spaces, the Winix 9800 air purifier takes up a bit more space in your home than the other best air purifiers we tested. Our testers reported that its boxy dimensions made it more complicated to put in a room without being noticeable, but the modern design and sleek exterior prevent it from being an eyesore. “I usually cough at night from allergies, and ever since getting the purifier, I am coughing very little, if at all,” our tester said. “It really seems to work and is pretty simple to maneuver, but it is quite large and I had to rearrange furniture for it. If you have a small space, I wouldn’t recommend this one.” Price at time of publish: $330 Product Details: Room Size: Up to 2,420 square feet; AHAM verifide up to 500 square feet | CADR: Not listed | Noise Level: Not listed | Dimensions: Not listed | VOC Filtration: Yes Keep in Mind: On its highest setting, this air purifier is quite loud and could be disruptive to sleeping or conversation. If your goal is to purify the air in a smaller room in your house, you don’t need to splurge for a massive unit designed for a much bigger space. Instead, there are many small air purifiers on the market that will effectively filter the air in your home without costing a fortune. The Toppin Comfy Air C2 air purifier aced our lab tests when it came to removing pet hair and smoke from the test environment, reducing PM 2.5 levels to a good range and eliminating particles in the air in 10 minutes. Since we used the same size of room to challenge this unit as we did with much larger units, we were expecting the air purifier to take much longer than others to remove toxins from the air. However, it worked almost as quickly as the larger units, making it the best air purifier for small spaces. We also loved how compact this unit is at just 6.7 inches in diameter and 13 inches tall, but it still circulates air five times per hour in a room that’s 215 square feet. This means the unit will be able to constantly and efficiently keep up with any dust, dander, mold, or other particles your home may contain. You won’t be able to connect this air purifier to an app or pair it with a voice-controlled device, but our testers said this didn’t bother them. Instead, they found the user-friendly display to be more than enough, offering multiple fan speeds, a power button, a nighttime mode that turns off the display lights, and a filter change light. It has three built-in filters—a pre-filter for pet hair, a carbon-activated filter for smoke and odors, and a HEPA filter for capturing 99.97% of particles in your air. Our tester shared that her roommate doesn’t experience allergy symptoms as often or as severely since she started using this air purifier in her small apartment. This air purifier’s only flaw is its noise level. Though it emits only 21 decibels of sound on low mode (quieter than a conversation across the room), it reached 45 decibels on its highest setting during our tests. We’d recommend using this air purifier on low mode at night while you’re sleeping to avoid being disrupted. However, our tester appreciates the white noise it provides. Price at time of publish: $100 Product Details: Room Size: 215 square feet | CADR: 150m³/h | Noise Level: Between 21 and 45 decibels | Dimensions: 6.7 x 6.7 x 13 inches | VOC Filtration: No Keep in Mind: It’s not Energy Star certified. One of the biggest pros in purchasing a small air purifier is its ability to move with you from room to room. Whether you work in an enclosed office, want to improve the air quality in your RV or camper, or you simply want flexibility with where you use your home appliances, the best portable air purifiers are lightweight enough to take with you just about anywhere. Our testers particularly liked the Koios air purifier, which circulates air five times an hour in rooms up to 215 square feet and weighs just 2.6 pounds. Like many of the larger air purifiers we tested, this device has three separate filters to thoroughly trap and remove different types of particles from your home including dust, pollen, pet hair dander, smoke, odors, and more. During our tests, we found that the unit was able to reduce PM 2.5 levels in the room from a hazardous level to a “good” one in 10 minutes—almost as fast as the larger units we tried. The Koios air purifier is also certified ozone-free, so it doesn’t use ozone gasses to remove pollutants from the air—a feature Mendez says is important to look for when considering the best air purifiers. We liked that it has an auto mode that will increase or decrease the fan speed, depending on your room’s air quality. You can also set a timer, change the fan speed, or turn it off or on directly from the front of the device. Keep in mind that this unit is not Energy Star certified, so it will consume more energy than other devices of the same size with Energy Star certifications. However, because it’s a smaller device than air purifiers for large rooms, it may still cost less to operate than a bigger unit. “It’s super quiet and compact, but you can tell the air feels cleaner in my office,” our tester, who uses the air purifier all day long on its lowest setting. “I like that it can sit on my desk and not make a lot of noise. I’d recommend it as long as you’re using it for small spaces.” Price at time of publish: $76 Product Details: Room Size: 215 square feet | CADR: Not listed | Noise Level: Not listed | Dimensions: 6.3 x 6.3 x 10 inches | VOC Filtration: Yes For larger rooms, we recommend the Winix 9800 Air Purifier, which quickly cleans particles out of the air and is designed to work in spaces up to 2,420 square feet.

Our Testing Process

Our team of experts spent three days in our lab in Des Moines, Iowa, putting some of the best air purifiers to the test to see which ones improved the air quality most efficiently. We exposed the air purifiers to smoke, pet hair, and dust in an enclosed space, then tested out different settings and compared the air quality of the room periodically throughout the test. This helped us determine which models were able to remove particles in the air, how long it took to do so, and what particles each purifier was unable to capture. Additionally, our testers carefully examined each air purifier to determine its quality and overall value compared to its price. We tried all of the settings and noted anything that stood out compared to others on the market, including any features and reports offered via a connected app. After gathering up all of our testers’ insights, we created a list of the best air purifiers for allergies, dust, smoke, and more. Once our lab tests were complete, we had a team of testers use the air purifiers in their own homes for an entire month, operating them every day to see how well they worked in the real world.

What to Know About Air Purifiers Before Shopping

Room Size

One of the most important factors to consider when shopping for the best air purifiers is the size of the room you intend to place it in. The larger the room, the more powerful your purifier will need to be in order to effectively cycle through all the air and remove particles. According to the Association of Home Appliance Manufacturers, an air purifier’s efficiency rating (clean air delivery rate, also known as CADR) should be equal to two-thirds of your room’s area. This means that a room with 120 square feet should have a CADR rating of at least 80 to work effectively.

Features and Capabilities

You’ll also want to find an air purifier that has a variety of settings and an adequate number of features to help you understand and improve your room’s air quality. When we tested air purifiers in our lab, we tried out every feature the devices offered to determine how well they worked and if they were actually valuable. The best air purifiers offer app connectivity so you can read reports on how the air quality of your room has changed over time, change settings remotely, and even check the moisture and temperature levels of your room. Your air purifier should also have multiple fan speeds that can be controlled directly on the device, a display that shows your room’s air quality, and a light that will turn on when the filter needs replacing. “[Another] rating you need to check is the MERV rating of the air filter,” Mendez says. “This minimum efficiency reporting value measures the size of the particles the filter will remove. The higher the MERV rating, the better the filtration. HEPA filters are normally rated MERV 13 or above.”

Device Dimensions

Depending on the size of the room and how much space you have, you will likely also need to consider the air purifier’s dimensions when picking out an air purifier. The larger the room, the more space the air purifier will probably take up, so be sure to look at the size of the device you’re considering to make sure you have space for it.

Other Air Purifiers We Tested

Honeywell HPA 104 Hepa Air Purifier

When testing the Honeywell HPA 104 Hepa Air Purifier in our lab, we found that it was effective at removing particles from the air, but it took more time to do so than other models. While it offered different fan speeds and settings on the machine itself, it didn’t have app connectivity and only worked in rooms up to 155 square feet, so we chose to feature other units in our list of the best air purifiers.

Pure Enrichment PureZone Mini Portable Air Purifier

Though we liked the compact size and lightweight design of this portable air purifier, we found during testing that it wasn’t very effective at removing particles from the air. While many other models could reduce PM 2.5 levels from hazardous to good in under 10 minutes, the Pure Enrichment mini air purifier levels remained hazardous (though they decreased slightly).

Levoit Core P350 Pet Care True HEPA Purifier

Our testers noted that while they loved the design and durability of the Levoit Core P350 Pet Care True HEPA Purifier, they weren’t as impressed by its other features. It doesn’t offer app integration, and its features seemed very standard across all of the air purifiers we tested. Additionally, it was not as quick to remove dust, pet dander, airborne contaminants, and smoke from the air as other models, so we chose to feature other air purifiers in this story instead.

Your Questions, Answered

What type of particles can an air purifier capture?

Air purifiers are a great solution to help improve the quality of the indoor air you breathe on a daily basis, but they aren’t all equal when it comes to capturing pollutants. When we tested air purifiers in our lab, we exposed them to smoke, dander, and pet hair, then checked the air quality over time to see how well each device captured and removed these pollutants from the space. The best air purifiers will have built-in HEPA filters, which can remove 99.97% of pollen, dust, airborne contaminants, mold, and any particles that are 0.3 microns, according to the EPA. Since airborne particles that are 0.3 microns in diameter are the most penetrating particle size, HEPA filters will work even better on particles larger or smaller than this. However, you’ll want to make sure the purifier you’re buying has a HEPA filter and not another type of filter, as other filter types may not work as well. “To filter gasses, choose a portable air cleaner with an activated carbon filter or other filter designed to remove gasses,” says Tim Carroll, EPA spokesperson. “Note that there are no widely used performance rating systems for portable air cleaners or filters designed to remove gasses. Activated carbon filters can be effective, provided that there is a large amount of material used in the filter.”

How often do I need to change my air purifier filter?

According to Hunter Pure Air, you should plan to change your air purifier’s filter every 6 to 12 months, though this can depend on how much pollution is in your air and how often you run the machine. The best air purifiers will have a filter change light to indicate when to replace the filter, eliminating any guesswork.

How often should I run my air purifier?

If possible, you should leave your air purifier on at all times, as this allows it to continuously remove particulate matter in your home and more accurately detect how your air quality changes over time. However, many devices have different fan settings, a timer function, and even a sleep mode that allow you to customize how and when your device runs.

Can an air purifier keep me from getting sick?

Though your air purifier shouldn’t be treated as the number one defense against illness, it can minimize your exposure to airborne illnesses, according to Mendez. “Indoor air quality also matters for the transmission of airborne infections, such as influenza, measles, or COVID-19,” Carroll says. “Indoor Air Quality (IAQ) affects everyone, especially the most vulnerable—children, the elderly, and people with health conditions like asthma and heart disease. In addition to using an air purifier, Carroll recommends trying to address indoor air quality solutions at the source. This includes opening doors and windows to help remove contaminants like dust, airborne contaminants, or other irritants and using a bathroom or kitchen fan. “Strategies must be adapted to specific pollutant problems. … Ventilation is generally counterproductive for pollen, for example, or in the case of wildfires,” Carroll says. “Mold is best controlled by keeping building materials dry and keeping relative humidity below 60%. … Surface cleaning (vacuuming or damp wiping) helps control accumulation of dander and other allergens in dust.”

Who We Are

Samantha Jones is an associate commerce editor at Better Homes & Gardens, writing and editing stories about the best patio furniture, pillows, robot vacuums and other home products worth buying. For this story, she spent several days researching important features in the best air purifiers, then compared her findings with insights gathered from our lab tests in Des Moines, Iowa. She also interviewed Kenneth Mendez, president and chief executive officer of AAFA, and Tim Carroll, representative of the Environmental Protection Agency, for their expertise on this topic.

​​What is BHG Recommends?

Next to all of the products on this list, you may have noticed our BHG Recommends seal of approval. Products that earn the seal have been put through rigorous testing to make sure they’re worth a spot in your home. We buy most of the products we test ourselves, but occasionally we are provided samples by companies if buying isn’t an option. In these cases, we use the same testing criteria we use to test the purchased products and we let you know that we got it for free to remain as transparent as possible about our picks. Looking for more products that have earned our BHG Recommends seal of approval? Check out our picks for everything from picnic blankets to humidifiers.