Coway Airmega 400S vs Coway Airmega 250S
Side-by-side comparison based on published product information. Check Amazon for current price and availability.
How we evaluate products
We compare published manufacturer specifications, manuals, support policies, and relevant public guidance. We do not present unpublished laboratory or in-home measurements as our own testing.
Features and services can change, so confirm current details with the manufacturer before buying. Affiliate commissions do not determine our editorial criteria.
In a nutshell
Coway Airmega 400S vs Coway Airmega 250S: two AirPurify picks compared across 9 published specifications. Use the feature table below to match published specifications to your room, filtration, and noise requirements. We do not assign an overall score without retained independent test evidence.
Key facts
- CADR:
- 328 / 328 / 400 CFM (Smoke / Dust / Pollen) vs 249 / 261 / 230 CFM (Smoke / Dust / Pollen)
- Coverage:
- 1,560 sq ft (2 ACH); 3,120 sq ft (1 ACH) vs 465 sq ft (4 ACH); 930 sq ft (2 ACH); 1,860 sq ft (1 ACH)
- Noise level:
- 22-52 dB(A) vs 22-54 dB(A)
- Power:
- 66 W vs 64 W
Key takeaways
- Coway Airmega 400S — Dual-sided Max2 filtration moves a strong volume of clean air
- Coway Airmega 250S — Wi-Fi with IoCare+ app, voice control, scheduling and an app-based timer
AirPurify· Updated July 20, 2026· How we evaluate products
Feature comparison
| Feature | Coway Airmega 400S | Coway Airmega 250S |
|---|---|---|
| CADR | 328 / 328 / 400 CFM (Smoke / Dust / Pollen) | 249 / 261 / 230 CFM (Smoke / Dust / Pollen) |
| Coverage | 1,560 sq ft (2 ACH); 3,120 sq ft (1 ACH) | 465 sq ft (4 ACH); 930 sq ft (2 ACH); 1,860 sq ft (1 ACH) |
| Noise level | 22-52 dB(A) | 22-54 dB(A) |
| Power | 66 W | 64 W |
| Filter type | 2 washable pre-filters + Max2 filter set (activated carbon + HEPA) | Washable pre-filter + Max2 filter (activated carbon + HEPA) |
| Filter life | Max2 filter set 1 year; pre-filters washable | Max2 filter 1 year; pre-filter washable |
| Warranty | 1 year (parts); 5 years (motor and electronic parts) | 1 year (parts); 3 years (motor and electronic parts) |
| Dimensions | 14.8 x 22.8 x 14.8 in (W x H x D) | 18.5 x 19.7 x 8.3 in (W x H x D) |
| Weight | 24.7 lbs | 20.5 lbs |