Coway Airmega Mighty review: a sleek and powerful air purifier

This powerhouse unit made light work of purifying the air in my home – but its design may not be for everyone

Airmega Mighty Air Purifier
(Image credit: Future)
Homes & Gardens Verdict

This powerful unit purifies the air and removes bad odors with ease, but its volume and boxy design won't appeal to everyone.

Reasons to buy
  • +


  • +

    Brilliant odor reduction

  • +

    Money-saving eco mode

Reasons to avoid
  • -

    Noisy on top setting

  • -

    Boxy Design

  • -

    No remote

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I never imagined an air purifier would become one of my must-have home essentials. Like many, I was more concerned about the pollution outside my home than the air quality inside. But the reality is, our indoor air can be just as, if not more, polluted.

So, when I was given the opportunity to test drive Coway’s most popular air purifier, The Airmega Mighty, I was intrigued to see how it would fare against pet odors and common household allergens.

This compact yet powerful unit promised to deliver excellent performance without the need for complicated functions or hefty energy consumption. So I put it through its paces with a series of real-life tests to see if it lived up to its reputation, and whether it's a contender for the best air purifiers.

Coway Airmega Mighty: Specifications

A Coway Airmega Mighty Air Purifier

(Image credit: Coway)
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Room coverage1,748 square feet
CADR (Clean Air Delivery Rate)234 (smoke) / 248 (dust) / 232 (pollen)
FilterPre-filter + Deodorization filter + True HEPA filter + Vital Ionizer
Filter life expectancyDeodorization filter (6 Months), True HEPA filter (1 Year)
Air quality indicatorGood (blue) / moderate (purple) / unhealthy (red)
Airflow5 settings (Auto / 1 / 2 /3 / Eco)
Timer1, 4, 8 hours
Noise levels24.4 - 53.8 dB
Power4.9 W - 82 W
Dimensions (H x W x D)16.8 x 18.3 x 9.6 inches
Weight12.3 lbs / 5.9 kg

Coway Airmega Mighty: Price

These days you can purchase a quality air purifier for anything from $100 to $500+. The Coway Airmega Mighty Air Purifier typically retails for $229, but it's often available for less than $200 during sales – putting it firmly in the mid-to-low range for value. You can purchase it directly from Coway, or from major retailers like Amazon and Walmart.

Replacement filters will typically set you back $59.79, but they can sometimes be found for as low as $30 on Amazon, making maintenance relatively affordable.

Coway Airmega Mighty: Unboxing & setup

An Air purifier with its filters removed

(Image credit: Future)

Unboxing the Airmega Mighty is extremely straightforward. The unit comes well-packaged with minimal plastic, primarily used to protect the filters. To set it up, you simply open the front hatch, remove the strips holding the pre-filter, and remove the charcoal and HEPA filters from their plastic bags.

Once you've installed the filters in the proper order (as shown in the manual) the only other step is to pop the cover back on and plug it in. The entire process is quick and hassle-free, allowing you to get the device up and running in no time.

Coway Airmega Mighty: The design

An air purifier next to a potted plant

(Image credit: Future)

The unit has a compact and boxy body with a circular air intake on the front and a top-mounted fan for air output. My unit is white, but the Airmega Mighty is also available in a black finish, which is often cheaper during sale season.

Although the air purifier has a plastic finish, it feels sturdy and has a clean, contemporary aesthetic. The overall design is reminiscent of an old iPod Shuffle, and I think it looks much more like a fancy Bluetooth speaker than an air purifier.

Personally, I'm not a fan of this design. As someone with a grandmillennial aesthetic, the device stands out for all the wrong reasons in my home and is too large to conceal conspicuously. That being said, the unit weighs around 15 pounds and has a convenient handle, which makes it easy enough to manoeuvre around my home. Plus, it could blend nicely with more sleek, modern aesthetics, and it's much less bulky than many air purifiers with this coverage.

Coway Airmega Mighty: Features

The Airmega Mighty Air Purifier

(Image credit: Future)

At the top of the air purifier, you'll find a user-friendly control panel (pictured above) which highlights the unit's main settings and functions:

Multiple fan speeds: There are five different fan settings: AUTO > 1 > 2 > 3 > ECO.

Ionizer: A dedicated button activates the ionizer, which helps improve air quality by dispersing negative ions that attach to pollutants.

Air Quality Indicator: The color-coded light indicates air quality – blue for good, purple for moderate, and red for poor. This feature can be turned off for night-time use.

Timer: Use the timer button to instruct the unit to turn off after 1, 4, or 8 hours.

Internally, the Airmega Mighty offers multi-stage filtration with three layers: an outer pre-filter for large particles, a carbon filter for smaller pollutants and odors, and a GreenHEPA filter for capturing fine particles.

The unit doesn't come with a remote control or any way to connect your device to a smart app, which I think is a bit of a design oversight. Unless you're happy with the 1, 4, or 8 hour timer increments, you'll have to manually turn the device on and off.

Coway Airmega Mighty: Performance

The Airmega Mighty Air Purifier

(Image credit: Future)

The Coway Airmega Mighty boasts impressive performance with a CADR rating of 247.5 for smoke, 232.3 for dust, and 241.3 for pollen. For the layman, this means that it will purify the air in an average US household with ease, and after running my unit continuously on eco mode for 3 weeks, I've noticed a huge improvement in my indoor air quality.

Test 1: Pet dander & odors

My cat spends most of his time lounging on the sofa in my living room, so I put the Airmega Mighty to the test by running it continuously in this room for a few days. Despite maintaining the same vacuuming routine, I quickly noticed that I was no longer suffering from my usual pet hair allergies. What's more, the room's 'catty' odor – which I thought I had gone nose blind to – was all but gone.

Test 2: Kitchen

I also put the Airmega Mighty through its paces by running it near to my stove when cooking. To do so, I positioned the air purifier a few feet away from the cooker and set it to ‘Auto Mode’ to see how sensitive it was to the pollutants in the air. Within 30 seconds of frying food, the machine turned from blue (indicating clean air) to red (indicating highly polluted air).

I was impressed to watch as the machine faded from red to dark purple and back to blue again over the course of a few short minutes. What’s more, it made light work of removing greasy odors from the air, too.

Test 3: Noise levels

The noise levels of this air purifier range from a whisper-quiet 36.8 decibels at the lowest setting to 58 decibels at the highest. Thankfully, when it’s set to eco mode or auto, it usually remains at the lowest setting – which is perfect for working or even sleeping. However, when it identifies highly polluted air, the machine gets quite loud and is hard to ignore. Unless I was extremely concerned about airborne pollutants, I don’t think I could run it at the top setting for very long without getting frustrated by the volume.

Test 4: Cost to run

This device has impressively low energy consumption, using only 0.08 kWh on auto mode over a 24-hour period. Plus, it has an ‘eco-mode’ that automatically stops the fan if no pollution is detected for 30 minutes, helping you save money.

Coway Airmega Mighty: Cleaning & maintenance

The Airmega Mighty Air Purifier

The outer pre-filter after a month of continuous use.

(Image credit: Future)

Maintaining the Airmega Mighty is simple and straightforward. Every 2-4 weeks, I wipe the external body with a clean microfiber cloth to remove dust and I use a damp cloth for anything tougher. I also gently clean the pre-filter with a vacuum, as this helps extend its lifespan.

The user manual recommends cleaning the air sensor, air inlet, and outlet every 2 months and provides easy-to-follow instructions for doing so.

When it's time to replace the Deodorisation filter or the GreenHEPA filter, the unit will let you know, as the reset indicator will blink. I haven't had to do this yet, but going by how easy it is to clean the unit, I'm sure it will be an easy process.

Coway Airmega Mighty: The verdict

Overall, the Coway Airmega Mighty Air Purifier is an excellent choice for those seeking an efficient and affordable air purifier. It makes light work of purifying the air and stands out in its ability to reduce pet odors and other unpleasant smells.

I think this unit would be perfect for a medium-sized household with dogs, as it's a touch too large and loud for small apartments but is well suited to households with pets.

Despite its boxy appearance and loud top setting, it outperforms many smaller devices and represents great value. So, if you're looking for an effective air purifier that won't break the bank, the Coway Airmega Mighty is definitely worth your consideration.

The H&G team tests all of our products before we recommend them. I used the Coway Airmega Air purifier in my home for two months before writing this review and experienced how it works firsthand. If you want to learn more about how we test products, you can visit our dedicated page.

Gabriella Dyson
Head of Solved

Gabriella is Head of Solved at Homes & Gardens. She is a DIY enthusiast and a lover of all things interior design, often found antiquing or browsing the aisles of her local hardware store. 

She has a particular passion for historic buildings and is in the process of renovating a Victorian coachhouse in the British countryside. 

For much of the past decade, Gabriella has worked as a freelance writer, crafting copy for national publications and renowned homeware brands. Most recently, she worked on Homebuilding & Renovating Magazine, focusing on case studies for the magazine and website, as well as writing features about issues surrounding historic and listed building projects.