Why it matters
The Coway Airmega 400 is a large-room / whole-floor air purifier that its maker rates for 3,120 sq ft.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 3,120-square-foot rating implies about 1,997 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 83 times an hour.
Filtration: HEPA. Quietest setting, per the maker: 22 dB. Power draw: 66 W.
Price-wise it sat in the middle third of the 57 large-room / whole-floor models we cover when we checked; the button shows today's price.
It qualifies for our lists Best Air Purifiers for Large Living Rooms, Best Air Purifiers for Home Offices, where it is ranked against every model that meets the same rule.
Its rated room size of 3,120 square feet is one of the largest ratings we cover: 146 of the 152 purifiers with a stated figure come in lower, and the range runs from 62 square feet to 4,800 square feet.
Compared with the Coway Airmega Halo: rated room size 3,120 sq ft here vs 1,898 sq ft; power draw 66 W here vs 38 W.
The listing gives dimensions of 14.8 x 22.8 x 14.8 in and a weight of 24.7 lbs.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 3,120 sq ft
- Large open rooms
Look elsewhere if
- Whole-home filtration on its own
- Removing gases without a substantial carbon stage
Pros and cons
Pros
- Rated for 3,120 sq ft
- Low setting 22 dB
- 66 W draw
Cons
- Filters are an ongoing cost
- Size to the room at 4.8 air changes per hour
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Price | $649 | Maker |
|---|---|---|
| Product weight | 24.7 lbs | Maker |
| Dimensions (seller) | 14.8 x 22.8 x 14.8 in | Maker |
| Room coverage | 3,120 sq ft | Maker |
| Wattage | 66 W | Maker |
| Filter type | HEPA | Maker |
| Noise (seller) | 22 dB | Retailer |
Alternatives worth comparing
More air purifiers we cover
- Blueair ComfortPure 3-in-1 T10i Air Purifier $499.99
- Shark Clean Sense HP102PET Air Purifier
- Levoit Core P350-P Pet Care Air Purifier $129.99
- Levoit Eleva 500X Air Purifier $259.99
- Rabbit Air A3 Ultra Quiet Air Purifier $749.95
All air purifiers, compared in one table · Every Coway product we cover
Final verdict
A solid choice for rooms up to about 3,120 sq ft. Confirm the model it fits before ordering.
Where to buy
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