Coway · Updated July 2026

Coway Airmega 400S: price & specs

Name: Coway Airmega 400S
Brand: Coway
Price: 749 USD
Availability: InStock

The Coway Airmega 400S costs $749, #16 cheapest of 21 air purifiers (median $299.99). It earns a Silver Deskmark — 48/100 pay-blind standing, #8 of 19 in class.

Verified Jul 7, 2026 · figures linked to their source in the table below

Check current price at amazon.com Recorded 2026-07-07 — live price may differ. As an Amazon Associate we earn from qualifying purchases.

Best for Smart sensor detected unnoticed cooking smoke and alerted the phone app; Cleared air from very unhealthy to good in about half an hour.
Skip if Expensive at $849, a $100 premium over the non-smart 400 is a dealbreaker.

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

Source: cowaymega.com verified 2026-07-07 ✓ corroborated verify in ledger

Coway Airmega 400S — Coway — Image: cowaymega.com (© Coway)

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 $299.99. 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 min of 22 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

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 · 2022-04-21

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.
Brand	Coway
Released	—
Cadr smoke (CFM)	328
Coverage (sq ft)	1560
Hepa	Yes
Filter type	Washable Pre-Filter + Max2 Filter (Activated Carbon + HEPA)
Noise db min	22
Smart	Yes
Energy star	—

Source: cowaymega.com (verified 2026-07-07) · corroborated by amazon.com. 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_sqft 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 null: 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 releaseDate are null. All six non-null specs (cadr_smoke_cfm, coverage_sqft, 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 →

Product	Price	Cadr smoke (CFM)	Coverage (sq ft)	Hepa	Filter type	Noise db min
Coway Airmega 400S this	$749	328	1560	Yes	Washable Pre-Filter + Max2 Filter (Activated Carbon + HEPA)	22
Rabbit Air MinusA2	$619.95	180	815	Yes	Pre-filter + Medium Filter + BioGS HEPA + Customized + Activated Carbon + Negative Ion Generator (6-stage)	25.6
Rabbit Air A3	$749.95	257	1070	Yes	Pre-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 2026-07-07.

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 $299.99.

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

Coway Airmega 400S (Coway): cadr smoke cfm 328, coverage sqft 1560, hepa Yes, filter type Washable Pre-Filter + Max2 Filter (Activated Carbon + HEPA), noise db min 22. Full sourced spec sheet verified 2026-07-07.