Coway
Airmega 400S
Based on 18 Reddit mentions
$649.99
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Most discussed features
Sentiment summary across the product areas Reddit users mention most.
Reddit mentions
Original Reddit posts and comments behind this analysis.
(Budget $2400) Going to return JASPR purifiers. What should I replace them with? (WILDFIRE SMOKE, POLLEN)
If you have high concentrations of particulates (e.g., pollen or smoke particles) and VOCs (which are gases), you need two types of air purifier. This is because most purifiers have very little activated carbon or other sorbent media by weight for gases/vapors/odors/VOCs. Instead, they're designed f
...sissasassafrastic in r/AirPurifiers
December 20, 2025 10:27 PM
2
Deciding between Winix C909 and Coway Airmega 400 (Bay Area, CA, USA)
Hi, I created the newest iteration of the Buying Guide. I didn't include the Coway Airmega 300 because in the past, the Coway Airmega 400 would be discounted frequently enough to justify its purchase instead. Annoyingly, there were no good Black Friday or Christmas sales for the Airmega 400 or Airme
...sissasassafrastic in r/AirPurifiers
January 6, 2026 12:31 AM
2
Anyone wanna talk me out of coway 400
Do you know the dimensions of the basement? A room's length x width x height are used to size purifiers. The largest room size the Coway Airmega 400 should be 492 sq. ft. with an 8 ft. ceiling. This is based on the AHAM 2/3 rule and the Airmega 400's Smoke CADR of 328 CFM running on the highest airf
...sissasassafrastic in r/AirPurifiers
September 27, 2025 11:55 PM
3
Airmega 450 vs Airmega 400
So the second screen capture is the Coway Airmega 400S. The Airmega 400S is the app connected version of the Airmega 400. The Airmega 450: Has higher Clean Air Delivery Rates (CADRs) than the 400/400S Is louder on high (57.7 dBA) than the 400/400S (52 dBA) Uses more energy at 72 W vs. the 400/400S p
...sissasassafrastic in r/AirPurifiers
July 30, 2025 5:17 PM
1
Recommendation for purifier in bedroom to filter out pollen, dust and cat hair/dander
Purifiers aren't good at reducing visible dust and pet hair. Both are large and heavy compared to "invisible" pollutants like PM10, PM2.5, and PM0.1. AHAM's 2/3 rule recommends CADRs be at least 2/3 of your room's area (assuming an 8 ft. ceiling). However, people with allergies or asthma should aim
...sissasassafrastic in r/AirPurifiers
November 24, 2025 5:10 PM
1