Best Air Purifiers For 300 Sq. Ft. Room in 2023

Last updated on June 13th, 2023

There are a lot of air purifiers that are marketed as best for 300 – 400 square feet area. However, many of them aren’t capable of cleaning rooms of this size: they either aren’t reliable or just do not have high quality HEPA air filters.

So here I present for you my list of the best HEPA air purifiers for 300 square feet area. But before we start a few notes about my methodology of picking air purifiers for this comparison.

• All air purifiers listed here either were tested by me, or people I know;
• All of them use true HEPA air filter that is capable of filtering airborne particles down to 0.3 micron at 99.97% efficiency;
• In addition, some of them were independently tested by Association of Home Appliance Manufacturers. Among other things, it tests air cleaners and assigns CADR ratings and area coverage for them. You see AHAM-Verifide text next to the room coverage of air purifiers that they have tested;
• All air purifiers can remove allergens and providing relief for people with a breathing condition. They can provide at least 4.8 air changes per hour (ACH), making them extremely viable for people who suffer from allergies or any other breathing conditions (e. g. asthma);
• These are portable air purifiers, meaning they can be easily moved from one room to another.

Now let’s see which air cleaner is the best for 300 sq. ft. room.

Coway Airmega AP-1512HH: Simply The Best

Coway Airmega AP-1512HH a.k.a. Mighty Air Purifier is the best air purifier not just for 300 sq. ft. area but also by and large. This air purifier made by the Korean company Coway is extremely efficient in removing any kind of pollutants in a room, whether it’s dust, pollen, tobacco smoke or any other kind of smell due to the 3-stage filter system that includes pre-filter, HEPA filter and Activated Carbon filter.

For anybody convenience it features auto mode. By simply pressing one button the air purifier will use the built-in particle sensor to detect any type of airborne irritant and based on its number, adjust the speed accordingly. For example, if you put it in the kitchen and start cooking, the Coway Airmega AP-1512HH will increase the speed the moment it senses the smell build up, keeping the air clean.

In addition, it has an ionizer. It helps to remove dangerous particles from the air and keep it fresh. The ionizer can be turned off at any moment if you don’t like it.

This Mighty air purifier has a certificate of Energy Star and consumes almost 78 Watts of power at the maximum speed. It’s not the most energy-saving air cleaner, but it delivers on the promises and that’s the most important thing.

And the last two positive notes about the Coway AP-1512HH: it is quiet even at maximum speed and maintenance costs do not exceed $100 due to the long filter lifespan and their low price tag.

Pros & Cons

Pros

• Efficiently cleans spaces up to 361 sq. ft. in a short time.
• Excellent choice for seasonal allergy relief
• Auto Mode adjusts fan speed based on air quality in real-time.
• Eco Mode conserves energy by turning off the fan when air quality remains purified
• Real-time air quality indicator with the option to turn off the light
• Filter alerts for timely maintenance
• Ultra quiet operation
• Comes with a 3-year limited warranty

Cons

• Some LEDs cannot be turned off, which may be inconvenient for those who prefer a completely dark room.

Winix PlasmaWave 5500-2 w/ Washable Filter

Winix PlasmaWave 5500-2 has an identical cleaning system to the Coway AP-1512HH that incorporates pre-filter, HEPA filter, Charcoal filter and optional ionizer that is called PlasmaWave that can be turned off as well. Winix is also a Korean company (coincidence?) and manufactures most of its appliances there.

This air cleaner has similar area coverage, but it was certified by AHAM and it stands at 360 sq. ft. If you struggling with allergies or asthma, this is an ideal air purifier to put in a 300 sq. ft. room, as you can run it at lower speed, so it will produce even less noise but keeping the air fresh and clean.

The Winix can also be used at night due to the feature called “Sleep mode”. In this mode the air purifier runs almost silent, producing only light white noise that does not disturb in any way.

Another interesting feature I have to mention is its washable filters (pre-filter and Carbon). Most air purifiers do not allow for washing of their filters (except for pre-filters), but the Winix does. As a result, it greatly extends the life of the filters, reducing the operating costs that do not exceed 100 USD including electricity bills.

Pros & Cons

Pros

• True HEPA filter captures 99.97% of airborne pollutants, allergens, and dust particles as small as 0.3 microns
• Washable AOC Carbon Filter
• PlasmaWave technology breaks down odor and removes allergens

Cons

• Dust bypasses the screen if snaps are not pushed in fully, causing gray buildup on the carbon filter
• Snaps disengage with force when removing the dirty screen, resulting in a messy cleanup
• Limited usefulness of the air quality sensor, as it only detects odors and not dust or pollen particles
• Bright lights on the unit cannot be turned off, making it annoying in brightly lit or dark rooms
• Turbo mode is noisy, limiting practicality in quiet settings like watching TV

Alen BreatheSmart 45i: Quiet, Great for Allergies & Heavy Smoke

What makes Alen BreatheSmart 45i to stand out are:

• The ability to clean air in 300 sq. ft. rooms while keeping the noise levels extremely low for an air purifier;
• Filters customization: 4 custom filters are available for purchase and 3 of them specifically target allergies (including allergies from pet smell, hair and dander) and odor, while the last one shows great examples of removing any kind of smoke (tobacco, wildfire, etc.) in a room.
• The Alen company provides a lifetime warranty if filter subscription is active at the official store.

However, the positive sides come at a cost: the BreatheSmart 45i retails at above $400, and filters aren’t cheap either. However, if you are ready to use the best solution for any kind of air pollutants and do not put with any kind of disturbing noise, then it’s the best what you can get for your medium-sized room.

It also comes with WiFi support, so you can control the air purifier manually from a distance if you do like the auto mode for some reason.

The quiet operation makes the Alen BreatheSmart 45i an ideal choice for your 300 sq. ft. bedroom to keep the air clean from any allergens, odors, dust and germs.

Pros & Cons

Pros

• Traps allergens, pollen, fur, pet dander, mildew, and aerosolized viruses
• 3-Stage H13 True HEPA filtration captures 99.99% of particles as small as 0.1 microns
• Laser Smart Sensor detects airborne particles and displays air quality with different colors
• Suitable for various spaces and applications

Cons

• A little loud
• Filters could be expensive
• Lack of integration with Wi-Fi or smart home devices

Medify Air MA-40: Best for Virus Removal

Medify Air MA-40 is also an extremely popular air purifier that comes under $350 per one unit. It’s not quiet, but features large 3-in-1 medical-grade HEPA filters that remove all types of irritants, including viruses and bacteria. A HEPA H14 filter is available as a replacement, and it features even better particles removal down to 0.1 micron. It is a great news, as most of viruses fit into the category of 0.1 – 0.3 micron particle size.

The MA-40 features Auto and Sleep modes, timer, and child lock. Basically, the features you should expect for a machine of such magnitude from Medify.

However, the noise levels aren’t that uplifting. At the maximum speed it produces a whopping 66 decibels of sound that is somewhere between the normal conversation and office sounds. On a positive side, the powerful motor and excellent air filter clean the air quickly and thoroughly, so most of the time this air  purifier won’t be used at the maximum power.

In addition, the ionizer (passed CARB, available for shipping to California) makes the air smell fresh after each cleaning procedure.

Pros & Cons

Pros

• Removes viruses from the space
• Ultra-quiet operation
• Easy-to-use features, including a touch screen operation panel with timer, fan speed, and filter replacement indicator
• Makes a noticeable difference in air quality, reduces coughing, and improves breathing
• Sleek design

Cons

• Noisy
• Filter replacement cost are high compared to other reviewed models

Blueair Blue Pure 311 Auto: Excellent for Tobacco Smoke

Blueair Blue Pure 311 is a great air purifier if you are a smoker and your main concern is to remove cigarette smoke from any room whether it’s kitchen, living room, basement or bedroom up to 388 sq. ft. (yet it will clean the air from smoke in 400 square feet area as well). This air cleaner has passed AHAM certification and is sure to make the air clean from smoke and other types of pollutants, but mostly dust and pollen.

Blueair has also managed to keep the power consumption at only 3 Watts in Sleep mode, making it viable to run 24/7 for months without touching anything. This will keep the air clean throughout the whole time at a low maintenance costs: a few dollars per year for electricity and only $40 for the replacement filter every 6 month.

Pros & Cons

Pros

• Reduces allergies and clears sinuses
• Noticeable difference in air quality and smell
• Easy setup and user-friendly design
• Multiple mode settings and indicator lights for air quality
• Quiet operation on auto and low settings.
• Effective in removing odors and smoke
• Compatible with third-party filters
• Great for pet owners and allergy sufferers
• Automatic air sensing function

Cons

• Pricey OEM filter replacements
• Boost mode is loud and not suitable for everyday use
• Light indicator sometimes is buggy

Honeywell HPA200: Old But Gold

Best Deal

Honeywell HPA200 is a fairly old air purifier designed by the US company Honeywell. As any other air purifier I have reviewed here, it can be used for rooms over 300 sq. ft., but when compared to the Coway, Winix, Alen, Medify or Blueair, the CADR ratings are lower and, therefore, the room coverage is also affected in a negative way.

The HPA200 also doesn’t have a pre-filter, resulting in the HEPA filter wearing down more often. However, the replacements are cheap (at $20 per one unit), so it is not a big deal.

I recommend getting the Honeywell only if it’s sold at a discount; in other instances the air purifiers listed above are simply better at filtering bacteria, odors and viruses from the air.

Pros & Cons

Pros

• Helps remove stale air and pet odors effectively
• Reduces the amount of dusting required
• Compact size and easy to move around.
• Affordable

Cons

• Noise level can be loud on higher settings, may disturb sleep
• May require repositioning to ensure even coverage in larger rooms
• Timer function is not very useful for specific needs
• Lacks a pre-filter

See also:

• Air Purifier for 3000 Square Feet
• Air Purifier for 2500 Square Feet
• Air Purifier for 2000 Square Feet
• Air Purifier for 1500 Square Feet
• Air Purifier for 1200 Square Feet
• Air Purifier for 1000 Square Feet
• Air Purifier for 800 Square Feet
• Air Purifier for 600 Square Feet
• Air Purifier for 500 Square Feet