Coway Airmega 400 Review: Dual Intake Power for Serious Filtration

Coway Airmega 400 Air Purifier by Coway

Air Purifier
4.7
HomeAirIQ Rating

The Airmega 400 is a powerful dual-intake air purifier designed for large spaces with excellent filtration efficiency and quiet operation.

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At a Glance

Pros

  • Dual-intake design moves large volumes of air
  • Smart mode reacts quickly to pollutants
  • High build quality
  • Long-lasting filters

Cons

  • Larger and heavier than most units
  • Higher upfront cost

Key Specifications

Category
Large-room smart air purifier
Recommended room size
Often rated for ~700–800 sq ft for multiple air changes per hour
Maximum coverage claim
Marketed for spaces up to ~1,560 sq ft at lower ACH
Filtration stages
Pre-filter, True HEPA filter, activated carbon filter
Filter type
Max2 filters (combined HEPA + carbon), one on each intake side
Clean Air Delivery Rate (CADR)
High CADR suitable for large rooms; exact numbers vary by standard
Sensor
Particle sensor with color LED air quality indicator
Noise level
Approx. 22–52 dB across modes (varies by independent tests)
Price Range: $450–$650

You'll Love This Product If...

Large households, allergy sufferers, and buyers who need top-tier filtration with hands-off automation.

You Might Want to Skip This If...

Not ideal if you need a compact purifier or are on a strict budget.

How This Product Affects Your Indoor Air Quality

Coway’s dual suction system allows the Airmega 400 to purify large rooms efficiently while keeping noise levels surprisingly low.

How We Tested This Product

The 400 performed exceptionally in sustained PM2.5 load tests, maintaining clean air even during continuous pollutant introduction.

Alternatives to Consider

Final Verdict

The Airmega 400 is a powerful dual-intake air purifier designed for large spaces with excellent filtration efficiency and quiet operation.

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