Why it matters
The Coway Airmega 450 is a large-room / whole-floor air purifier that its maker rates for 3,285 sq ft, with a smoke CADR of 439 CFM.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 3,285-square-foot rating implies about 2,102 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 88 times an hour.
Filtration: HEPA. Quietest setting, per the maker: 23.7 dB. Power draw: 72 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 Wildfire Smoke, 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 3,285 square feet is one of the largest ratings we cover: 149 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 350: rated room size 3,285 sq ft here vs 2,640 sq ft; smoke CADR 439 CFM here vs 352 CFM; power draw 72 W here vs 62 W.
The listing gives dimensions of 13 x 13 x 29 in and a weight of 24.9 lbs.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 3,285 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 3,285 sq ft
- Smoke CADR 439 CFM
- Low setting 23.7 dB
- 72 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 | $499 | Maker |
|---|---|---|
| Product weight | 24.9 lbs | Maker |
| Dimensions (seller) | 13 x 13 x 29 in | Maker |
| Room coverage | 3,285 sq ft | Maker |
| Wattage | 72 W | Maker |
| Filter type | HEPA | Maker |
| CADR (smoke) | 439 CFM | Retailer |
| Noise (seller) | 23.7 dB | Retailer |
Alternatives worth comparing
More air purifiers we cover
- Airpura I700 Air Purifier (I700-CRM) $1,149.98
- Levoit Vital 100 Air Purifier $119.99
- Levoit Core 200S-P Smart Air Purifier $89.99
- Levoit Vital 200S-P Smart Air Purifier
- AirDoctor AD1500 $399
All air purifiers, compared in one table · Every Coway product we cover
Final verdict
A sensible choice for rooms up to about 3,285 sq ft. Confirm the model it fits before ordering.
Where to buy
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