Coway Airmega 400 vs Airmega Mighty
Bottom line
In our scoring the Airmega AP-1512HH Mighty wins decisively, 8.5/10 (Excellent) to the Airmega 400's 4.0/10 (Limited), a 4.5-point gap. Most of it is honesty and cost rather than hardware: the Mighty's room claim is backed by its own verified CADR, its filters cost about a quarter as much a year, and it carries Energy Star and CARB listings the 400 does not. The 400 has two genuine advantages worth naming. It really does move more air, 400 cfm against 246, and it uses no ionizer at all where the Mighty has a defeatable one, so it scores higher on safety in our rubric, 8.0/10 to 5.0/10. In our view, buy the 400 only if you have a genuinely large open space and size it to the roughly 620 sq ft its CADR supports, not to the number on the box.
If you are choosing between Coway's flagship and its long-running mid-size unit, the honest comparison is not about which is better built. Both carry an AHAM-verified CADR, the independently checked figure for how much clean air a purifier actually delivers, and the Airmega 400 delivers more of it: 400 cfm at its highest verified figure against the Mighty's 246. Where it comes apart is the room claim and the bill. At the 4.8 air changes per hour we hold purifiers to, the 400's verified airflow covers about 620 sq ft, not the 1,560 sq ft on the box, because that headline number is rated at a gentler pace of roughly 2 air changes an hour. The Mighty's 361 sq ft claim sits inside what its own CADR supports. Filters run $129 a year for the 400 and $36 for the Mighty, which over five years with the device is about $1,294 against $410.
| 400 cfm (AHAM-verified) | CADR (independently verified?) | 246 cfm (AHAM-verified) |
| 3.0 | Verified Performance30% | 10.0 |
| 1.0 | Total Cost of Ownership25% | 7.0 |
| 3.0 | Certification15% | 10.0 |
| 8.0 | Safety15% | 5.0 |
| 8.0 | Practical Fit15% | 10.0 |
FAQ
- Is the Coway Airmega 400 better than the Coway Airmega AP-1512HH Mighty?
- In our scoring the Coway Airmega AP-1512HH Mighty rates 8.5/10 and the Coway Airmega 400 4.0/10. In our scoring the Airmega AP-1512HH Mighty wins decisively, 8.5/10 (Excellent) to the Airmega 400's 4.0/10 (Limited), a 4.5-point gap. Most of it is honesty and cost rather than hardware: the Mighty's room claim is backed by its own verified CADR, its filters cost about a quarter as much a year, and it carries Energy Star and CARB listings the 400 does not. The 400 has two genuine advantages worth naming. It really does move more air, 400 cfm against 246, and it uses no ionizer at all where the Mighty has a defeatable one, so it scores higher on safety in our rubric, 8.0/10 to 5.0/10. In our view, buy the 400 only if you have a genuinely large open space and size it to the roughly 620 sq ft its CADR supports, not to the number on the box.
- Does the Airmega 400 really cover 1,560 sq ft?
- It depends how thoroughly you want the air cleaned. At about 2 air changes per hour, a gentle once-over, that figure holds. At 4.8 air changes per hour, the brisker turnover we hold purifiers to, its AHAM-verified CADR supports about 620 sq ft. We flag that gap so you are not sizing a room to the optimistic number.
- Which is cheaper to own?
- The Mighty, by a wide margin. Its filters run about $36 a year against $129 for the 400, and with the device included we compute roughly $410 over five years against about $1,294. The 400 also costs $649 up front to the Mighty's $230.
- Is the Mighty's ionizer a drawback?
- It is the one place the 400 scores better. The Mighty has a defeatable ionizer that is CARB-listed for ozone compliance, which earns partial credit in our rubric; the Airmega 400 has no ionizer or ozone-producing stage at all, which earns full credit. If you want nothing of that sort in the room, that is a real point for the 400, and you can also simply switch the Mighty's off.