Coway Airmega 300S Air Purifier: Trusted Review & Specs

The Airmega 300S (AP-1515G) was a huge gamble from Coway, yet one that really paid off six months into our testing. A huge jump from the previous low-range air purifiers, with mid-range to high-range cost, premium design, and a bunch of new Smart features. It totally replaced the Coway AP-1511FHE, which is designed to reach the high-end level but will never achieve it. By far, we’ve finished our Airmega 300S Review to help Breathe Quality’s readers know if they should buy this air purifier or not.

Update: The Airmega Icon is the newest system from Coway and costs nearly the same as the Airmega 400S.

Coway Airmega 300S ranks A+ in our air purifier ranking list. We give the biggest and most thorough database of air purifier reviews in the world.

In Breathe Quality, we have reviewed all air purifiers under these sections. Also, we guarantee that:

  • We provide honest reviews (both pros and cons) so that everyone can make the best decisions.
  • We do not (and never will) exaggerate one product just to let you click the links and buy that product blindly.


airmega 300s review

  • Great air filtration process
  • Premium, strong design
  • Large room coverage
  • Smart features

  • Price fluctuation

The air purifier giant in South Korea, Coway, is truly the king of the East in the industry of air cleaning. Coway has everything going for it over any other air purifier brands with a long history like the IQAir, Blueair or Austin Air. The company puts much effort into the new Airmega brand, both in terms of technical features and marketing promotion. The Airmega 300S is no longer the best of its lineup, but it always is the beginning of a stunning concept. Now, you should be ready for our Airmega 300S Review.

Other Coway’s Air Purifier Reviews:

AIRMEGA 300s Price

Coway is calling the Airmega 300S the future of air purifiers, the embodiment of what it’s been trying to achieve for many decades. And it has good reasons to back up the ideas, as the Airmega 300S has an undeniable beauty as well as lots of high-end features that will create an all-new experience for Coway customers.

And the Airmega 300S is exactly the air purifier we’ve been demanding from a well-known brand for years, a world away from the increasingly tired designs that many others keep repeating. For that change, the Airmega 300S charges us a lot more for the privilege, which we have never seen in any previous Coway devices. However, we all want to know if the Airmega 300S is worth having or not.

The Airmega 300 (the no-app model) starts at $549, while the Airmega 300S will cost you at least $649. The price of the Airmega 300S is exactly the same as the next non-app model, the Airmega 400. Although it’s expensive for sure, you can use our deal below for a great discount, so the Airmega 300S can go as low as $425. Also, I suggest you look for the Coway AP-1512HHS or Airmega 250S as a smaller smart air purifier version, both made by Coway.

The Airmega 300S will need to go head-to-head with its rivals, the Winix XLC and Levoit EverestAir, both of which have a more powerful fan and a better asking price. We should also mention the Rabbit Air MinusA2, which is our former champion of the best air purifier. If you’re looking for the lifetime warranty, perhaps either the Alen BreatheSmart or Medify MA-112 could be your next purchase.

We also notice the presence of the Dyson Pure Cool Tower and Dyson Pure Cool Link in the same price range. These air purifiers, besides having a true HEPA filter, have amazing cooling fan power to help you survive the summerpurifiers, besides having a true HEPA filter, have amazing cooling fan power to help you survive the summer. The Dyson Pure Hot+Cool, with a little bit higher cost, will come with the heating power as well.

Top Airmega 300S deals right now

Coway Airmega The Smarter App Enabled Air Purifier (Covers 1256 sq. ft.), Compatible with Alexa.

The beautiful White edition of the high-end air purifier. Pay as low as $23/month. Free Shipping. 30-day Satisfaction Guarantee.

Related post: Best air purifier 2023.

AIRMEGA 300S Design and Size

As I’ve already mentioned, Coway has taken a fresh approach to design with the Airmega family. An air purifier with a unique design that we will definitely realize as a device from Coway Airmega.

We can’t see any familiar old parts in this Airmega 300S, from the iPod-shape design of the Coway AP-1512HH to the traditional design in the Airmega 200M. What you’re feeling when having an Airmega 300S for the first time is that this is a premium air purifier. It feels more expensive, with a brighter color tone as well as an intuitive light alert right at the center of the Airmega 300S.

If you are looking for the standard version named Airmega 300, you should check it below. Both versions have the same design and power, only with the difference of the Wi-Fi connectivity feature.

Coway Airmega 300S Air Purifier: Trusted Review & Specs

Instead of using a stand, this Airmega 300S has four legs, which give us a feeling of a stable and solid build. Also, the air purifier is quite heavy at 21.4 lbs, and I don’t feel that it could be broken by anything. Sadly, without casters, you can’t move the air purifier anywhere.

Compared with the Airmega 400S, this air purifier is slightly smaller, with only 21.2 inches in height and 13.6 inches in both depth and width. However, such minor modifications do not make us more difficult to use than the Airmega 300S. In day-to-day use, I can easily touch the control panel on top.

Speaking of the airflow design concept, the Airmega 300S uses a 360° air intake. However, unlike the previous air grills from Coway, the grills of the Airmega 300S consist of small holes to increase the resistance against large objects. This concept is similar to that of another Korean brand, the Winix C535, but this is the only part we can compare between these air purifiers. Airmega 300S is, of course, at a much higher level.

On top of this Airmega 300S, this company has made a bigger air outlet grill that covers almost the whole top. There is only a small on/off button on the right and two reset buttons on the left. Coway truly wants its flagship to be easy to use.

airmega 300s review


Related post: Best air purifiers for bedroom.

AIRMEGA 300S Filters

Coway is always proud of its air cleaning system, which consists of at least four different air filters. Normally, to decide the performance of one air purifier, we always look at the number of its air filters and the types of air filters used first. But like I said earlier, the Airmega 300S is a huge gamble for this brand. Not only does it have a new design concept and a brand new name, but it also has an all-in-one air filter.

  1. Pre-filter – First, the Airmega 300S still uses a powerful washable pre-filter, which is available to help you capture large objects of contaminants. Remember to dry the pre-filter before re-installing it.
  2. Max2 filter – Combining both an Activated Carbon filter and a True HEPA filter, this filter can capture up to 99.97% of airborne particles smaller than 0.3 microns. It also reduces more than 99 percent of volatile organic compounds and fumes, such as NH3 and CH3CHO.

Actually, the concept of an all-in-one air filter is not new. Blueair has been used since the very beginning, and even new American brands like Alen and Levoit are in favor of using all-in-one air filters.

Now, the flagships of Coway are using the Max2 filter, which maintains the same high quality as the previous True HEPA filter of this company and also improves the Activated Carbon filter. On my day-to-day use of the Airmega 300S, this air filter stacks up more and more impurities, and I can breathe easier thanks to it.

For a strict test, I chose the Blueair Classic 405 and Alen BreatheSmart to test the Airmega 300S. Because both the non-Wi-Fi Airmega 300 and the Wi-Fi-enabled Airmega 300S are using the same internals, I believe that the performance test can be used for both devices.

With a room coverage way smaller than what Coway advertised, the Airmega 300S scored an efficiency of 99.95%, trapping any allergens as small as 0.3 microns, while the Blueair Classic 405 was 99.97%. The Alen BreatheSmart was down to only 98.5%, and if you try the Alen BreatheSmart FIT50 in the same test, its efficiency was only 97%.

airmega 300s review

The Airmega 300S uses exactly the same quality air filter as its brother – the Airmega 400S. Maybe this is the top reason why the air filter cost is too high, up to $99. For an air filter that is only good for one year, will you scream in pain? But wait, the Blueair Classic 405‘s filter costs $59, but needs to be replaced after 6 months. As you can see, $99 is only $0.02 per day for an air purifier. That’s decent, right?

Related post: Best air purifiers for allergies.

AIRMEGA 300S Room Coverage

Airmega 300S has larger room coverage than any previous air purifiers from this brand, with 1256 square feet to use. That’s quite large, but in the high range, where all air purifiers are for large rooms, it makes sense.

Remember that the room coverage is only for two air changes per hour. If you use this air purifier in a room of 628 square feet, the ACH rating will double to 4X.

The ACH of Airmega 300s is 2X to 4X. For a high-range air purifier, this ACH is on par with the Rabbit Air MinusA2, as the Airmega 300S will clean your room every 15 minutes.

The CADR of Airmega 300S is again not told in the manual. But through many tests, I recorded a reliable CADR of 300 Dust/ 310 Smoke/ 340 Pollen (cfm). For a room coverage of 1256 square feet, this CADR rating is quite insufficient, and the Airmega 300S will need more time to clean the room.

Related post: Best large room air purifiers.

AIRMEGA 300S Sound

Coway has a good tradition of making its air purifiers operate in sleep mode. To achieve that, this company always uses a smaller fan and sacrifices the fan power for the low noise level.

On the lowest fan speed, the Airmega 300S has a very low noise level of 22 decibels, which is exactly the noise level of rustling leaves. This is even better than the ultra-silent operation of the Rabbit Air MinusA2.

Even if you are running on the highest speed, the noise level is only 52 decibels (dB), and because the Airmega 300S produces white noise, you can easily sleep while running this air purifier.

Related post: Best air purifiers for baby.

AIRMEGA 300S Power Consumption

One of our most FAQs is “Do air purifiers use a lot of energy?” The fact is, you need to use an air purifier for a long time to be efficient. It is especially important for large room air purifiers, as they always have a big fan and need more energy to operate.

The power consumption of the Airmega 300S is only 57 watts, which is quite reasonable to use. Actually, in this price range, others like the Blueair Classic 405 and Alen BreatheSmart consume nearly the same energy as the Airmega 300S.

The Airmega 300S is also an air purifier with an Energy Star rating for being energy efficient. This is the government-backed symbol to ensure you get the most efficient air purifier.

So to say, if you run the Airmega 300S for 8 hours per day, it would cost you $21 each year.

Related post: Best air purifiers for pets.

AIRMEGA 300S Additional Features

The keyword for any modern, high-end air purifier is “Smart”. Airmega 300S is not an exception, as it is one of the most progressive air purifiers at the moment. And we will see if this air purifier is truly what Coway should be applauded for or not.

First is the real-time air quality monitor of this Airmega 300S, which is indeed the Smart Sensor, and will detect the indoor air quality every minute. Below are all the statuses of the LED ring that Coway uses to show you how clean or dirty your indoor air is.

airmega 300s review

Moreover, the Airmega 300S will switch to Auto Mode and automatically adjust the fan speed according to the room’s current air quality. For example, if your room’s air quality is very unhealthy, the Airmega 300S will run at its highest speed to clean the room faster. Otherwise, it will keep running at the lowest speed for good air quality.

Coway is also the only brand that features Eco Mode, a signature name for all Coway products. When the air quality in the room remains purified for 10 minutes or more in Eco Mode, the Airmega 300S will completely turn the fan off to conserve energy. This is a very smart concept, and it is only possible with a very accurate air sensor. Therefore, we can think of the Eco Mode as the unique selling point of all Coway products.

The smart Wi-Fi connectivity function is another plus for this air purifier. With the IOCare app, you will get real-time air quality notifications, set the unit timer, and even activate the air purifier remotely when connected to Wi-Fi. Notice that the Airmega 300 edition won’t have this feature.

Finally, you have a manual sleep mode, which in fact runs the Airmega 300S at the lowest fan speed. The indicator for filter replacement works great, too.

Related posts:

1, Best air purifiers for smoke.

2, Best air purifiers for dust.

3, Best air purifiers for mold.

AIRMEGA 300S Customer Service

As one of the top electronic brands in Korea, Coway is somehow as huge as Samsung. This brand not only carries out clean innovations for the customers, but Coway also delivers its direction as Coway Trust. That’s why Coway always places a strong focus on its customers and community. With global subsidiaries and regional dealerships that serve over 60 countries, you should believe in the customer service of the company.

Moreover, you can contact Coway’s customer service via phone at 800-285-0982 or via email at Normally, customer service will try to contact you within 24 hours.

All air purifiers made by Coway have their motor and electronic parts warranted for 3 years, while other internals are warranted for 1 year.

Top Airmega 300S deals right now

Coway Airmega The Smarter App Enabled Air Purifier (Covers 1256 sq. ft.), Compatible with Alexa.

The beautiful White edition of the high-end air purifier. Pay as low as $23/month. Free Shipping. 30-day Satisfaction Guarantee.

Our verdict

The design of the Coway Airmega 300S is sleek, and the features are so, so good. This air purifier is exactly the first step for Coway into the high-range market, and that is the new standard for mid-range air purifiers.

Coway Airmega 300S Air Purifier: Trusted Review in 2024
Coway Airmega 300S Air Purifier: Trusted Review & Specs

Coway Airmega 300S Reviews and Specs (Air Purifier Trusted Reviews in 2024). ✓ Cleaning Power: True HEPA ✓ Wi-Fi: Great ✓ Value: 4.8/5 ✓ Certified Review.

Product Brand: Coway

Product Currency: USD

Product Price: 425

Product In-Stock:

Editor's Rating:
  • Performance
  • Features
  • Annual Cost
  • Design
  • Price


If you are spending money for this Airmega 300S, then you won’t be disappointed.