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Coway

Coway Airmega Mighty: the downsides first

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#2 of 8
$$HEPA + carbonUp to 362 sq ftScore 4.0/5
4%
of Amazon ratings are 1–2 stars
(checked 2026-10-10)The listing pools the white, black and Mighty2/MightyS variants (29,196 ratings).

A proven, long-lasting purifier with cheap filters and over 29,000 Amazon ratings, but it is loud on high, power-hungry at top speed, and its odor filter is weak.

Top complaints

  • Loud on high

    HouseFresh measured 60.1 dB at top speed and says it is louder than many tested models. TechGearLab scored noise 5.6/10, citing about 55 dB and vibration on high.

    Source: HouseFresh review, TechGearLab
  • Weak odor filter

    HouseFresh and TechGearLab both say its carbon is impregnated fabric, which is less effective than pelleted carbon. Amazon's review summary calls odor removal mixed, with some owners complaining of a bad smell.

    Source: HouseFresh review, TechGearLab, Amazon.com product page (Customers say)
  • Power-hungry, bright light, frequent filter swaps

    Wirecutter measured 68.7 W on high and HouseFresh 75.3 W. Some Amazon owners find the blue air-quality light too bright for sleep. TechGearLab notes carbon changes every 6 months and HEPA every 12.

    Source: Wirecutter, HouseFresh review, Amazon.com product page (Customers say), TechGearLab

What owners love

  • Extremely durable

    Wirecutter ran test units 24/7 for years, including through a small office flood, with virtually no drop in performance even past filter life.

    Source: Wirecutter
  • Strong cleaning

    Wirecutter averaged more than 99% smoke removal in 30 minutes on high. Amazon shoppers call it effective and report allergy relief.

    Source: Wirecutter, Amazon.com product page (Customers say)
  • Cheap filters, easy to replace

    HouseFresh says its OEM filters are some of the cheapest it has seen and generics are widely available. Amazon owners praise the simple filter replacement.

    Source: HouseFresh review, Amazon.com product page (Customers say)
Good for
  • Bedrooms and living rooms up to about 360 sq ft
  • Proven long-term reliability
  • Low filter costs

Scores (tap for why)

  • Cleaning performance4.5
    Why 4.5?Over 99% smoke removal on high (Wirecutter); cleaning drops sharply at speed 2 (HouseFresh).
    Source: Wirecutter, HouseFresh review
  • Quietness3.0
    Why 3.0?Quiet on low and medium and an Amazon positive, but 55-60 dB on high (TechGearLab, HouseFresh).
    Source: TechGearLab, HouseFresh review, Amazon.com product page
  • Filter cost4.5
    Why 4.5?Some of the cheapest OEM filters HouseFresh has seen (filter pack $57.49), and generics are widely available.
    Source: HouseFresh review
  • Controls & app3.0
    Why 3.0?Simple controls with auto mode and full display shutoff (Wirecutter), but no app or child lock (HouseFresh), and the Wi-Fi version's app is buggy (Wirecutter).
    Source: Wirecutter, HouseFresh review
  • Durability5.0
    Why 5.0?Wirecutter's units ran 24/7 for years without degrading; quality is the top Amazon positive.
    Source: Wirecutter, Amazon.com product page

What experts say

  • Wirecutter (NYT): Runner-up after 11 years as top pick: top cleaning and durability; it uses more power on high than the Mighty2, and the app version (AP-1512HHS) is buggy.
  • HouseFresh: 4/5: solid value but a little dated; power-hungry, loud at top speed, weak fabric carbon, no app or child lock.
  • TechGearLab: Scored 72 (#4 of 12): strong filtration and low running costs; loud and vibrating on high, and the lights can't be turned off.
Check price on AmazonWe don't list prices — they change daily. Paid link.

If that catch is a deal-breaker

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Head-to-head

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