The Front Desk Review

Coway · Updated October 2026

Coway Airmega 400S: price & specs

Coway Airmega 400S. Every price and spec below is linked to its source and dated — no guesses.

Source: cowaymega.com verified ✓ corroborated verify in ledger

SilverDeskmark51/100#6 of 19 in class

The Coway Airmega 400S is listed at $749 on cowaymega.com as of 2026-10-20, #16 cheapest of 21 air purifiers (median $349.99); other retailers may be lower. It earns a Silver Deskmark — 51/100 pay-blind standing, #6 of 19 in class.

Verified Oct 20, 2026 · figures linked to their source in the table below

Cheapest air purifiers: Levoit Core 300S — $149.99

Seen at

Each figure is what that seller's own page published on the day we read it — not our price of record, and not a live quote. Follow the link for what it costs right now.

At Amazon

Amazon.com$612sold by Amazon.com(as of — Details)

Details

Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon.com at the time of purchase will apply to the purchase of this product.

The figure is the featured (buy box) listing at the moment shown, from Amazon's Creators API — not a page we read, and not necessarily the lowest listing.

CERTAIN CONTENT THAT APPEARS ON THIS SITE COMES FROM AMAZON. THIS CONTENT IS PROVIDED 'AS IS' AND IS SUBJECT TO CHANGE OR REMOVAL AT ANY TIME.

See it at Amazon.com Live price at the store — may differ from the dated listed price above. As an Amazon Associate we earn from qualifying purchases.
Coway Airmega 400S — Coway
Image: cowaymega.com (© Coway)

Price history

$749
2022-08-16↑12% on record2026-10-20

How we know these prices

The curve above is one dated record of this product's price — our own tracking combined with Internet Archive snapshots of a public page that published the figure, reaching back before we began: this product's own source page wherever the archive holds one, otherwise the named retailer or reference page the point was read from. Every archived point links to the snapshot that proves it, so the host it came from is on the record and you can verify each one yourself.

Verify each point — 7 archived snapshots

Is the Coway Airmega 400S a good buy?

At $749, the Coway Airmega 400S is #16 cheapest of the 21 air purifiers we track, where the median is $349.99. On the spec sheet, its coverage of 1560 sq ft is the highest of the 22, its cadr smoke of 328 CFM is above the median of the 15, and its noise db of 22 min is below the median of the 19.

Evidence of Record

Our data

No independent lab has measured this product yet. 1 outlet has it on record by mention only, with no hands-on measurements published to weigh its claims against — a gap in the evidence, not a verdict on the product.

A coverage record, not a rating. How we count

Review consensus · sourced & dated

What reviewers say about the Coway Airmega 400S

Only one whitelisted tester — Digital Trends — published a hands-on review of this exact Coway Airmega 400S. Its writer praised the smart air-quality sensing and large coverage but flagged the high price, bulky footprint and flaky Wi-Fi reconnection.

Based on 1 review · 1 lab-tested · 2022-04-21

Tested by Digital Trends

Consistently praised

  • Smart sensor detected unnoticed cooking smoke and alerted the phone app
  • Cleared air from very unhealthy to good in about half an hour
  • Large coverage (up to 1,560 sq ft), more than many competitors

Commonly flagged

  • Expensive at $849, a $100 premium over the non-smart 400
  • Bulky (~25 lbs) and sits idle taking up space most of the day
  • Trouble reconnecting to Wi-Fi after being unplugged
  • Did not noticeably relieve allergies during weeks of use

Where reviewers disagree Single-source: only Digital Trends reviewed this exact model, so cross-source agreement cannot be assessed.

The sources (1)

Digital Trends lab-tested ·

I did, and the air went from very unhealthy to moderate to good in the space of a half hour.
I also had some trouble getting the Airmega back online after having it unplugged for a couple days.
While it's nice to know my air is pretty clean, that price is a lot to pay for something that will sit idle — and take up a decent chunk of space — for most of the day.

Specifications

Price (US)$749 List price $749.00 on cowaymega.com (Coway's official US store), shown as regular price $749.00, as of 2026-07-07. Amazon listing (B01C9RIAFS) sells the same model but shows a fluctuating third-party/import price, so the manufacturer list price is used.
BrandCoway
Released—
Cadr smoke (CFM)328
Coverage (sq ft)1560
HepaYes
Filter typeWashable Pre-Filter + Max2 Filter (Activated Carbon + HEPA)
Noise db (min)22
SmartYes
Energy star—

Source: cowaymega.com (read 2026-10-20) · corroborated by amazon.com (read 2026-07-07).

How we checked

cowaymega.com (Coway's official US store) product page for the Airmega 400S confirms CADR 328 (Smoke) / 328 (Dust) / 400 (Pollen) cfm, room coverage 3,120 ft² at 1 air change/hour and 1,560 ft² at 2 air changes/hour, filter composition "Washable Pre-Filter + Max2 Filter Set" / "Max2 Filter (Activated Carbon + HEPA)", noise 22~52 dB(A), Wi-Fi with the Airmega mobile app plus voice control (smart mode: auto/sleep/eco), and a $749.00 regular list price; coverage (sq ft) uses the manufacturer's headline 1,560 ft² (2 ACH) figure. The Amazon listing (ASIN B01C9RIAFS, model 111012) corroborates the exact 400S model: title "Coway Airmega 400S App-Enabled Smart Air Purifier (Covers 1,560 sq. ft.), True HEPA Air Purifier with Smart Technology, Compatible with Amazon Alexa and Google Home, White (111012)". Energy Star is left blank: the manufacturer page makes no certification claim, so certification is not asserted. No release year is stated for the 400S on either fetched page, so release and release date are left blank. All six recorded specs (cadr smoke (CFM), coverage (sq ft), hepa, filter type, noise db (min), smart) were re-verified verbatim against the fetched source page.

Is the Coway Airmega 400S worth it vs cheaper air purifiers?

Coway Airmega 400S against its closest cheaper and pricier air purifiers on the specs that matter — every value sourced. See all 21 ranked

ProductPriceCadr smoke (CFM)Coverage (sq ft)HepaFilter typeNoise db (min)
Coway Airmega 400S this$7493281560YesWashable Pre-Filter + Max2 Filter (Activated Carbon + HEPA)22
Rabbit Air MinusA2$619.95180815YesPre-filter + Medium Filter + BioGS HEPA + Customized + Activated Carbon + Negative Ion Generator (6-stage)25.6
Rabbit Air A3$749.952571070YesPre-filter + Medium + BioGS HEPA + Customized + Dual Hive Charcoal + Negative Ion Generator (6-stage)20.3

Frequently asked questions

What do reviewers say about the Coway Airmega 400S?

Only one whitelisted tester — Digital Trends — published a hands-on review of this exact Coway Airmega 400S. Its writer praised the smart air-quality sensing and large coverage but flagged the high price, bulky footprint and flaky Wi-Fi reconnection. Praised: Smart sensor detected unnoticed cooking smoke and alerted the phone app; Cleared air from very unhealthy to good in about half an hour; Large coverage (up to 1,560 sq ft), more than many competitors. Flagged: Expensive at $849, a $100 premium over the non-smart 400; Bulky (~25 lbs) and sits idle taking up space most of the day; Trouble reconnecting to Wi-Fi after being unplugged; Did not noticeably relieve allergies during weeks of use. (From 1 tester review, 1 lab-tested.)

How much does the Coway Airmega 400S cost?

The Coway Airmega 400S has a US price of $749 (List price $749.00 on cowaymega.com (Coway's official US store), shown as regular price $749.00, as of 2026-07-07. Amazon listing (B01C9RIAFS) sells the same model but shows a fluctuating third-party/import price, so the manufacturer list price is used.), as of 2026-10-20.

How does the Coway Airmega 400S compare on price?

At $749, the Coway Airmega 400S is #16 cheapest of the 21 air purifiers we track, where the median is $349.99.

Has the Coway Airmega 400S's price dropped?

No — since 2022-08-16 the Coway Airmega 400S has risen 12.1%, from $668 to $749; the lowest we have recorded is $479 (2024-09-06).

What is the lowest price the Coway Airmega 400S has been?

The lowest we have recorded for the Coway Airmega 400S is $479 on 2024-09-06.

Is now a good time to buy the Coway Airmega 400S?

The Coway Airmega 400S is currently $749; the lowest we have recorded is $479 (2024-09-06). Every price is dated, so you can judge it against its own history.

What are the Coway Airmega 400S's key specs?

Coway Airmega 400S (Coway): Cadr smoke (CFM) 328, Coverage (sq ft) 1560, Hepa, Filter type Washable Pre-Filter + Max2 Filter (Activated Carbon + HEPA), Noise db (min) 22. Full sourced spec sheet verified 2026-10-20.

Price of record: $749 at cowaymega.com, 2026-10-20. Other retailers may be lower — check the current price:

See it at Amazon.com As an Amazon Associate we earn from qualifying purchases.

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