Coway Airmega 450 Review

Design and Features

• Gorgeous, space-saving design
• User-friendly controls
• Filter indicator

The Coway Airmega 450 is a tall air purifier (it’s designed for large rooms), but its cylindrical shape doesn’t take up much floor space. Both the top and sides have a modern style that’s similar to the popular fluted/reeding wall and furniture trend that’s actually a throw-back to the columns found in ancient Greece and Rome. This design adds texture and dimension, and keeps the air purifier from looking like a hum-drum machine. The air purifier is also available in two colors: white, and beige. 

It weighs 24 pounds, and has wheels that make it easy to roll on hard floors. However, the wheels don’t move at all on carpet. There’s a handle on the back, which is helpful when guiding the air purifier on hard floors, but it doesn’t help to move the air purifier on carpet. The only choice is to pick up the air purifier from underneath the bottom when it needs to be moved on a carpeted area. 

At the top of the air purifier (surrounding the control panel) is the air outlet area. The air inlet areas are on the side.

The control panel contains a variety of 1st-layer and 2nd-layer selections and indicators, including an air quality indicator, which is colour-coded to turn blue for good air quality, green for moderate air quality, yellow for unhealthy air quality, and red for very unhealthy air quality. There’s also an filtere replacement indicator, and the current PM info.

Controls include the power button, timer, light, timer, and a mode button to cycle through the four modes: Eco, Turbo, Sleep and Auto. I could also choose between the three fan speeds manually.

One of my only two complaints with the Coway Airmega 450 is that there are not enough fan speeds. I just finished testing the Dreame AirPursue PM20 Air Purifier, which has 10 speeds. I will admit that’s rather excessive, but at least 5 or 6 speeds would be nice.

However, I really like the Filter Lifespan Indicator, which shows the remaining filter life as a percentage. On some air purifiers, the filter replacement light comes on when it’s time to replace the filter. However, this is information that I’d like to have in advance, instead of finding out at the last minute. The filter lifespan indicator helps me plan ahead to ensure I’ll have a replacement filter on hand when needed.

 The air purifier can detect PM1, PM2.5, and PM10.

Coway has an app, but the Coway Airmega 450 is not one of the company’s air purifiers that can be used with it. There’s also no remote control. However, the control panel is so user friendly, that I didn’t consider the lack of an app or remote to be a problem, but it’s definitely something that needs to be included in the review.

Performance

• Adjustable sensitivity settings
• Choice of filters provide customized air purifying
• Can get loud to clean air effectively

I’ve had the Coway Airmega 450 Air Purifier since March, 2026, so I’ve had plenty of time to test it. Honestly, the air cleaning performance on the lowest settings are dismal. But on higher settings, the air purifier is stellar.

The Coway Airmega 450 Air Purifier CADRs are as follows: 439 smoke, 445 dust and 450 pollen.

These clean air delivery rates are almost double those of the average air purifier. In fact, very few air purifiers have CADRs in the 400 range, and this is one of the primary reasons I’m so impressed with the Coway Airmega 450. It’s designed for really large rooms, and can clean 3285 sq ft in 60 minutes. That, in and of itself, doesn’t sound impressive if you happened to be in that room waiting an hour for polluted air to be removed. But if the room is 1643 sq ft, it cleans the air in 30 minutes. And on, and on. 

I have a smoking neighbor, and the air purifier very quickly and effectively removes smoke from my home. When the fan is in auto mode, and she’s smoking by my bedroom, the fan speed increases considerably. It can get pretty loud, but if it’s cleaning my air, I will gladly put up with the increased volume. Normally, it only takes a few minutes (5 or 6) before the fan speed decreases.

The Coway Airmega 450 also does a good job of cleaning the air when I’m cooking, and when I’m spraying cleaning products into the air. 

When I initially started testing, I actually thought something was wrong with the air purifier, because it didn’t seem to detect anything. However, the air quality sensitivity level can be adjusted. Level 1 is sensitive, level 2 in general, and level 3 is insensitive. I changed the setting from level 2 to level 1, and the air purifier did a much better job of detecting air pollutants. 

The filtration system consists of a 3-in-1 filter with a vacuumable pre filter, HEPA filter, and activated charcoal. There are 3 filters to choose from. The Fresh Starter+ filter is standard, but the Allergen+filter also includes an allergen absorber, and the Intense Smoke+ filter includes a VOC absorber. The ability to focus on specific pollutants provides a more targeted and effective way to combat air pollution.

Regarding the noise level, it’s very quiet in Auto, Sleep, and Eco modes, and when on the first fan speed setting. However, the air purifier is considerably louder in Turbo mode or in speeds 2 or 3. The noise level can cross the 60dB mark on top speed (admittedly, my HVAC is almost always on, and that could contribute to the noise level being higher).

Maintenance is pretty easy. The pre-filter should be cleaned with a dry cloth or vacuum every 2 to 4 weeks. The air sensor should be cleaned every two months. Fortunately, the 3-in-1 filter only needs to be replaced yearly – based on running the air purifier eight hours a day in Turbo mode. 

The only other problem I had was occasionally getting the filter panel back on the air purifier. Sometimes it was a smooth process. Other times, the cover would not close securely. I reread the instructions several times, and even watched the video, but again, sometimes, it closed perfectly, and sometimes it didn’t.

Should you buy it?