Coway Airmega 400 vs Blueair Blue Pure 311i+
We compare the Coway Airmega 400 and Blueair Blue Pure 311i+ head-to-head on performance, features, value, and more. Here's which one wins.
Coway Airmega 400
Scored 9/10 in our testing
Coway Airmega 400
Large living spaces up to 1,560 sq ft needing powerful, efficient air purification
Blueair Blue Pure 311i+
Tech-savvy users who want app control and auto-adjusting purification
Score Breakdown
| Coway Airmega 400 | Category | Blueair Blue Pure 311i+ |
|---|---|---|
| 9.5/10 ✓ | Performance | 8.8/10 |
| 8.5/10 | Features | ✓ 9.3/10 |
| 9/10 | Ease of Use | 9/10 |
| 9/10 ✓ | Value | 8.5/10 |
| 9/10 ✓ | Overall | 8.9/10 |
Specs Comparison
| Coway Airmega 400 | Spec | Blueair Blue Pure 311i+ |
|---|---|---|
| Up to 1,560 sq ft | Coverage | Up to 929 sq ft |
| True HEPA + activated carbon | Filtration | HEPASilent with activated carbon |
| 350 CFM (smoke) | CADR | Wi-Fi, app control, air quality sensor |
| 22-52 dB | Noise | 23-53 dB |
| ~12 months | Filter Life | 250 CFM |
Coway Airmega 400
Pros
- + Massive 1,560 sq ft coverage
- + Dual-sided HEPA filtration
- + Real-time air quality display
- + Quiet at lower speeds
Cons
- − Large footprint
- − No app control without Airmega AP model
- − Replacement filters add ongoing cost
Blueair Blue Pure 311i+
Pros
- + Full app control with air quality monitoring
- + HEPASilent technology is whisper-quiet
- + Auto mode responds quickly to changes
- + Attractive fabric pre-filter in multiple colors
Cons
- − Covers less area than Coway Airmega 400
- − Replacement filters are pricey
- − Wi-Fi setup can be finicky
Our Verdict
Based on our scoring, the Coway Airmega 400 comes out on top with an overall score of 9/10. The Coway Airmega 400 is the gold standard for large-room air purification. Dual HEPA filters pull air from both sides simultaneously, cleaning a massive 1,560 sq ft space efficiently. The real-time air quality indicator and auto mode adjust fan speed intelligently. Replacement filters are reasonably priced for the coverage area.
Buy the Coway Airmega 400 on AmazonRead the full Best Air Purifiers for Large Rooms 2026 guide for complete reviews of all 5 products.