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When picking out the best large room HEPA air purifier, there are many factors to consider such as the filter types, coverage, fan speeds, ACH ratings, and more.

To make things easier for you, we’ve reviewed the top 5 HEPA air purifiers that have been made to perform well in large spaces. A buying guide is also available at the end that includes more details on large room air purifiers. By the end, you’ll have a better idea of the different features and how to go about choosing the air purifier that’s right for your home.

🏆 Editor’s Pick – Fellowes AeraMax 300

fellowes aeramax 300


  • PlasmaTRUE technology
  • AeraSafe microbial treatment
  • Sensors to detect air quality 
  • True HEPA filter

Fellowes AeraMax 300 has a true HEPA filter which is great for capturing 99.97% of small particles that are as small as 0.3 microns. In addition to this, a carbon filter has been fitted which is effective at purifying the air from odor-causing pollutants like smoke, cooking smells, smoke and odors from pets.

You’re provided with the option to use the PlasmaTRUE technology feature as well. This is an ionizing system that works by sending out charged particles into the air to bring them lower down to the ground where they’re easier to remove.

We liked how an AeraSafe antimicrobial treatment element has been included as it works to prevent fungi and mildew from accumulating inside the true HEPA filter. As a result, the filter can work effectively for longer.

Users have been liking how this air purifier can automatically detect pollutants in the air and adjust its setting accordingly. It’s an automated process that lets you keep the machine running all the time. With an ACH rating of 5x, this air purifier can effectively clean the air in rooms that are between 300 and 600 square feet.

Pros 👍
✔ True HEPA filter & carbon filter
✔ AeraSafe antimicrobial feature
✔ Automatically detects airborne pollutants
✔ Optional PlasmaTRUE ionizer

Cons 👎
✘ Blue light is brighter than some would prefer
✘ Can be noisy

View Fellowes AeraMax 300 on Amazon

RabbitAir MinusA2

RabbitAir Minus2A Air Purifier


  • True HEPA filter
  • Customized filter for germs
  • Negative ion generator available
  • Wall-mount design

A 6-stage filtration system has been implemented to this air purifier that includes a BioGS HEPA filter, pre-filter, medium filter, customized filter, activated carbon filter, and an ion generator.

The pre-filter and medium filter handle the larger particles so that the HEPA filter can focus better on purifying the air from microscopic pollutants. Their customized filter is awesome for getting rid of germs from the air and the activated carbon filter removes odor-causing pollutant particles.

With the optional negative ion generator, you can send out negatively charged ions that latch themselves onto pollutants to cleanse them from the air.

So, it’s a thorough air purifier that covers all of the bases when it comes to purifying airborne pollutants. It’s also great for covering large spaces with an ACH rating of 2x that can purify areas up to 815 square feet.

Users have been pleased to find that you can set up this air purifier standing alone or mount it to the wall where it’s out of the way.

Pros 👍
✔ 6-stage filtration
✔ Can be wall mounted
✔ Optional negative ion generator
✔ Covers 815 square feet

Cons 👎
✘ Scheduling features are tricky to use
✘ WiFi connectivity could be better

View RabbitAir MinusA2 on Amazon

Coway Airmega 400

coway airmega 400 product


  • Sensors detect air quality 
  • True HEPA filter
  • Sleep mode included
  • Activated carbon filter for odors

The Coway Airmega 400 has an ACH rating of 2x and can purify the air in spaces of up to 1,560 square feet. Therefore, it’s an excellent option to consider for especially large areas and it’s able to clean the air in rooms of up to 1,560 square feet twice every hour.

A true HEPA filter has been implemented that’s great for capturing microscopic particles that are 0.3 microns with a 99.97% success rate. The true HEPA filter works alongside an activated carbon filter that gets rid of the pollutants that cause odors, such as smoke, cooking smells, and odors from pets.

We were impressed with how a sensor has been fitted to this air purifier as it’s able to detect the quality of the air. As a result, it can make automatic adjustments to the fan speeds to clean the air accordingly. An LED ring has been integrated into the front of the air purifier that lets you know the cleanliness of your air at any time of the day.

You can take advantage of the sleep mode if you wanted to have this air purifier running all night while you sleep. It brings the fan speed down so that the machine creates less noise to avoid disturbing you.

Pros 👍
✔ Sleep mode included
✔ True HEPA filter & activated carbon filter
✔ Built-in sensors

Cons 👎
✘ Big & heavy
✘ Replacement carbon filters are expensive

View Coway AirMega 400 on Amazon

Alen BreatheSmart Fit50

alen breathesmart fit50 white


  • Quiet operation
  • Detects air quality 
  • Sensors & automatic fan speed setting
  • Lights-off mode available

We liked how the Alen BreatheSmart Fit50 can clean the air in large spaces of up to 900 square feet while also remaining quiet. This makes it a great air purifier to install in your home that works well without causing noise pollution.

The true HEPA filter that has been implemented removes pollutant particles that are as small as 0.3 microns with a success rate of 99.97%. In addition to this, sensor technology has been fitted that works to let you know the quality of the air in your home.

If the light is red or orange, it means that the air is dirty but if it’s blue, it means that the air has been cleared from most pollutants. A lights-off mode is available that lets you sleep properly without bright lights shining.

The sensors inside this air purifier also allow it to make automatic changes to its fan speeds depending on how dirty or clean your air is. It’s an awesome automated process that lets you keep the machine running all day and night.

Pros 👍
✔ Lights-off mode available
✔ Excellent sensors
✔ True HEPA filter

Cons 👎
✘ Some notice it makes a clicking sound
✘ Larger than some would prefer

View Alen BreatheSmart Fit50 on Amazon

Medify MA-112

medify air ma-112 whole house


  • Medical-grade H13 HEPA filter
  • Touchscreen control panel
  • Sleep mode included
  • 4 fan speeds available

With a CADR rating of 950 and the ability to cover up to 3,700 square feet, the Medify MA-112 air purifier is fantastic for purifying the air in large rooms. The machine can clean the air in spaces of up to 3,700 once every hour.

Moreover, a medical-grade true HEPA H13 filter has been implemented. This filter is highly effective at removing 99.97% of pollutant particles that are as small as 0.3 microns.

Users have been liking how a touchscreen panel has been included. This panel is easy to use and enables you to have an easy time when it comes to changing the various settings. You can use the touchscreen panel to switch between the 4 available fan speeds.

Furthermore, an optional ionizer feature is available that you can turn on and off. For those of you with young children in the house, you can set a child lock to prevent the settings from being tampered with.

You can have this air purifier running at night while you’re sleeping as a result of the sleep mode. With this mode on, the air purifier automatically switches to the lower fan setting to make less noise.

Pros 👍
✔ Medical grade H13 true HEPA filter
✔ Easy to use touchscreen panel
✔ Wheels on the bottom for transportation

Cons 👎
✘ Doesn’t remove cooking smells as well
✘ Display can’t be dimmed

View Medify MA-112 Air Purifier on Amazon

HEPA Air Purifiers Buyer’s Guide

What Is A HEPA Filter?

HEPA stands for High-Efficiency Particulate Air and it’s a type of filter that’s available in vacuums and air purifiers. The filter works by taking in the air where it’s able to filter out the pollutant particles before letting fresh air back out. These pollutant particles include smoke, pollen, pet dander, and dust.

Differences Between HEPA Filters

It can be difficult trying to find the right air purifier for your home since various models have different kinds of HEPA filters available. Air purifiers can have a range of HEPA filters that include a true HEPA filter, a HEPA-type filter, or just a HEPA filter.

If you’re after an air purifier that has the most effective filter for removing pollutant particles from the air, we recommend that you stick with the models that have true HEPA filters. This is because air purifiers that state they have a true HEPA filter have passed regulations set out by the United States Department of Energy.

Air purifiers that only have a HEPA filter mean that they haven’t put their model through these regulations which means you can’t be completely sure of how effective they are.

The best overall large room air purifiers have true HEPA filters that can remove up to 99.97% of airborne pollutant particles that are as small as 0.3 microns. The success rate for standard HEPA filters may be the same or lower but there’s no guaranteed way of telling. Therefore, the most reliable option is to go with true HEPA filters.

You may have also seen air purifiers that claim to have HEPA-type filters. HEPA-type filters are the least effective kind of filter as they haven’t passed any type of regulation and have a much lower success rate of being able to purify the air from microscopic pollutants. HEPA-type filters are only able to capture between 85 and 99% of pollutant particles that are 2 microns.

HEPA Filter Running Costs

When it comes to large room HEPA air purifiers, staying on top of filter replacements is crucial to ensuring that the machine can continue being effective at purifying the air. This is because these air purifiers are working harder by covering larger areas which means the filters are having to purify more air.

Some air purifiers have systems that let you know when it’s time to replace the HEPA filter. However, other air purifiers may not give you this luxury which means you’ll need to remember to replace the HEPA filters yourself.

HEPA filters should be replaced once every 12 to 18 months. If you use your air purifier more regularly, you’ll want to replace the HEPA filter once a year.

Therefore, there are running costs to using HEPA air purifiers to make sure that the machine can last longer and clean your air from pollutants. When it comes to carbon filters, they’ll need replacing every 3-6 months.

Furthermore, pre-filters will need to be cleaned every month and replaced when they become worn down.

Frequently Asked Questions

What does CADR stand for?

CADR stands for Clean Air Delivery Rate and was created by the AHAM (Association of Home Appliance Manufacturers). It’s a rating that was developed to help customers compare air purifiers as it refers to how effective the machine is at cleaning the air in rooms of certain sizes.

There are three CADR ratings to look out for that refer to smoke, dust, and pollen. The higher the CADR rating for these pollutants means that the air purifier is more effective at removing those pollutants from the air.

Where’s the best place to position an air purifier in a large room?

HEPA air purifiers use a fan system to draw in air to clean before releasing back out. Therefore, you’ll want to place these air purifiers in a place where they aren’t being blocked by furniture or walls.

We recommend that you keep HEPA air purifiers at least 4 feet away from furniture or walls to ensure that it has plenty of room to pull in air and let it back out once it has been cleaned.

What are the other common filters available with HEPA air purifiers?

Pre-filters and activated carbon filters are commonly available with many HEPA air purifiers. The pre-filter handles the larger particles so that the HEPA filter can focus on purifying the air from the microscopic pollutants. Therefore, pre-filters can help with the longevity and effectiveness of HEPA filters.

Activated carbon filters are great for capturing the odor-causing pollutant particles. These are odors in homes that may be caused by smoke, chemicals, pets, or cooking.


That concludes our review of what the best HEPA air purifiers for large rooms have to offer. Our number one pick is the Fellowes AeraMax 300 due to how it has sensors to automatically detect the air quality and a true HEPA filter to effectively get rid of the microscopic pollutants in the room.

You’ll also want to consider the other great air purifiers from our review as they include features that may be better suited to cleaning the air in your larger rooms. Hopefully, you can use our review and buying guide to pick the large room HEPA air purifier that’s best for your needs.

Check Fellowes AeraMax 300 on Amazon