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Pet Allergies & Dander

Coway Airmega 400 vs Airmega Mighty AP-1512HH

The same manufacturer sells one machine with third-party numbers and one without. For a pet household that difference decides it.

By Scooter M.

Published

Last verified

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The short answer

Buy the Airmega 400 if the room is over about 350 square feet: 376 certified smoke CADR across 583 certified square feet, 0.00 ppb measured ozone, no ion generator. The Mighty claims 233 CFM, is in no certification register, publishes no certified energy use and ships an unmeasured bipolar stage.

Comparisons on this site usually run across brands. This one runs inside a single brand, which makes it unusually clean: same company, same design philosophy, same retail channels — and two completely different states of evidence.

The numbers, side by side

Coway Airmega 400 vs Coway Airmega Mighty AP-1512HH
Airmega 400AP-1512HH Mighty
Smoke CADR376 CFM233 CFM
Dust CADR384 CFM246 CFM
Pollen CADR409 CFM240 CFM
Verified byENERGY STARNobody — Coway's own figures
Certified room size583 sq ft361 sq ft (Coway's own)
Advertised coverage1,560 sq ft (Coway)1,748 sq ft in 60 minutes
Annual energy (certified)366 kWhNot published
Electricity per year$67Not published
Power drawNot published77 W
Measured ozone0.00 ppbNot published
IonizerNoneBipolar device
Filter class (register)Composite FilterNot classified
Washable pre-filterNot documented in our sourcesYes
Published filter intervalNot published12 months HEPA, 6 months deodorization
Everything in the Airmega 400 column marked ENERGY STAR is checkable in a public database. Everything in the Mighty column comes from Coway. Both advertised-coverage figures are the manufacturer’s.

Electricity costs on this page use 18.34¢ per kWh, the U.S. average residential price for June 2026 from the U.S. Energy Information Administration, Electric Power Monthly, Table 5.3. Your rate is on your bill and is probably not this one; multiply the kWh figure by your own rate and you have your number.

On output, this is not a close comparison

376 against 233 smoke CADR is 61% more air. 583 against 361 square feet is the same gap expressed as coverage. Unlike most pairs on this site, these two are not interchangeable machines at different prices — they are aimed at genuinely different rooms.

Under AHAM’s two-thirds rule a 500 square-foot open-plan space asks for 334 CFM. The Airmega 400 clears it. The Mighty is not close, and buying the Mighty for that room is the single most common sizing mistake in this category — the calculator settles it in about ten seconds.

On evidence, they are in different categories

The Airmega 400 is listed in EPA’s ENERGY STAR room air cleaner database, which requires testing to ANSI/AHAM AC-1 through an EPA-recognized certification body and additionally publishes measured ozone emissions and certified annual energy use. Its ozone reading is 0.00 ppb and its technology classification is fan and filter — no ion generator.

The AP-1512HH is in neither that database nor AHAM’s directory. That does not make its figures wrong. It makes them unchecked, and it means the fourth filtration stage Coway describes as a “Bipolar Device” has no published ozone measurement from Coway or from anybody else.

Where the Mighty genuinely wins

Two things, and in a shedding household they are not trivial.

A documented washable pre-filter. Coway publishes one; our sources do not document one on the Airmega 400. Shed hair and coarse dander load a cartridge quickly, and a rinsable mesh in front of it extends the interval — the units that document one are a short list.

Published filter intervals. Twelve months for the HEPA stage and six for the deodorization filter. Coway publishes no interval for the Airmega 400 that we could source, and the absence of a schedule is the absence of half your running cost.

Quick picks

Both Coway models, plus the machine we would put in a pet bedroom instead.

#ProductBest forCertified CADRPrice
1
No photo
The Coway with third-party numbers

Coway Airmega 400

376 certified CFM across 583 sq ft, 0.00 ppb ozone, no ion generator.

Large rooms, verified Coway376CFM smoke
ENERGY STAR verified
2
Winix Winix C710
What we would buy at mid size

Winix C710

248 certified CFM, AHAM listed, 235 certified kWh, no ionizer.

Lowest running cost at living-room size248CFM smoke
AHAM VERIFIDE
3
No photo
The popular one, unverified

Coway Airmega Mighty AP-1512HH

233 CFM claimed, in no register, with an unmeasured bipolar stage.

The popular default, unverified233CFM smoke
Manufacturer-claimed

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The picks

The Coway with third-party numbers

Coway Airmega 400

Coway · model Airmega 400 (AP-2015F)

No photoNo manufacturer photograph in our sources for this model
Check price on Amazon

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The Coway that is actually in a certification register: 376 certified smoke CADR, 583 square feet, zero measured ozone. If you want a Coway, this is the one with third-party numbers.

ENERGY STAR verified

376 smoke / 384 dust / 409 pollen CFM · 380 PM2.5

Certified room size
583 sq ft
Energy / year
366 kWh
Our arithmetic
Electricity / year
$67
Air per watt
6.1 CFM/W
Noise
Not published
Measured ozone
0 ppb
Filter class
Composite Filter
Our arithmetic
AHAM rule, 500 sq ft
Clears it (334 needed)
Ionizer status

No ionizer — filtration only

ENERGY STAR classifies this unit 'Fan and Filter', 0.00 ppb measured ozone.

Why this matters if anyone in the house has asthma

376 certified smoke CADR across 583 certified square feet, with 0.00 ppb measured ozone and no ion generator. At 6.1 CFM per watt and $67 a year it is mid-pack on efficiency, and for a genuinely large pet household it is the Coway to buy.

The honest con: ENERGY STAR records the filter as a “Composite Filter” and does not classify it HEPA or HEPA-Type at all, so the filter-grade comparison this site normally makes cannot be made. Coway publishes no filter interval or price we could source for it either, which for a large machine is a meaningful blank.

The popular one, unverified

Coway Airmega Mighty AP-1512HH

Coway · model Airmega Mighty AP-1512HH

No photoNo manufacturer photograph in our sources for this model
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The most-recommended air purifier in this category, and the one with no third-party CADR to check. Coway's own figures are good; at 77 watts it is also the thirstiest machine here for its output.

Manufacturer-claimed

233 smoke / 246 dust / 240 pollen CFM

Certified room size
361 sq ft
Advertised coverage
1,748 sq ft in 60 minutes
Power draw
77 W
Noise
24-53 dB(A)
Our arithmetic
AHAM rule, 350 sq ft
Short (234 needed)
Ionizer status

Bipolar device — fitted

Coway lists a 'Bipolar Device' as the fourth filtration stage. Because this model is in neither register, there is no independent ozone measurement for it — and Coway does not publish one.

Why this matters if anyone in the house has asthma

The most-recommended air purifier in this category, and on Coway’s own numbers a capable mid-size machine — 233 CFM across 361 square feet, with the washable pre-filter and published intervals the Airmega 400 lacks.

The honest con: no register, no certified energy figure, 77 watts — the highest draw for its output of anything we cover — and a bipolar ionizing stage nobody has measured. We are not saying it is a bad machine. We are saying you cannot check it, and there are machines at this size you can.

What we would put in a pet bedroom

Winix C710

Winix · model C710

Winix Winix C710
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Nearly the same air movement as the AT41 for a third less electricity a year. If you can find it, it is the cheapest certified 380-plus square-foot unit to run.

AHAM VERIFIDE

248 smoke / 252 dust / 262 pollen CFM · 250 PM2.5

Certified room size
384 sq ft
Energy / year
235 kWh
Our arithmetic
Electricity / year
$43
Air per watt
6.2 CFM/W
Power draw
45 W
Noise
Not published
Measured ozone
1 ppb
Filter class
HEPA-Type
Our arithmetic
AHAM rule, 350 sq ft
Clears it (234 needed)
Ionizer status

No ionizer — filtration only

AHAM classifies this model 'Fan with Filter'.

Why this matters if anyone in the house has asthma

For a mid-size pet room this is the comparison the Mighty actually loses: 248 certified smoke CADR across 384 AHAM-certified square feet, no ion generator of any kind, and a certified 235 kWh a year at $43. That is more certified air than the Mighty claims, from a register you can search, on a machine that draws 45 watts against 77.

The honest con: ENERGY STAR classifies its filter HEPA-Type rather than HEPA and measures 1 ppb of ozone rather than zero, and Winix documents neither a washable pre-filter nor a filter interval for it — which in a shedding household is exactly where the Mighty pulls ahead. The C710 against the Mighty in full.

The verdict

Common questions

Which Coway should I buy?

The Airmega 400, if the room justifies it. It is the Coway with numbers somebody outside Coway has verified: ENERGY STAR lists it at 376 certified smoke CADR across 583 square feet with 0.00 ppb measured ozone and no ion generator. The Mighty is in neither register, publishes no certified energy figure and ships a bipolar ionizing stage with no ozone measurement from any source.

Is the Airmega 400 worth the step up from the Mighty?

It delivers 61% more certified air and covers 61% more room, so for a large or open-plan space the answer is straightforwardly yes. For a bedroom under about 350 square feet it is more machine than the room can use, and the Mighty’s documented washable pre-filter and published filter intervals become the more useful features.

What about the Airmega 400S?

Coway sells a 400S alongside the 400. We cover the AP-2015F specifically because that is the model number the ENERGY STAR register lists, and we do not transfer one model’s certified figures onto another model number — that is how unverified numbers get laundered into looking certified. If you want the app control, check the 400S in the register yourself before assuming the figures carry across.

Does the Mighty's bipolar device produce ozone?

Nobody publishes a measurement. Coway lists the “Bipolar Device” as the fourth filtration stage, the model appears in neither register, and Coway does not publish an ozone figure of its own. That is not an accusation — it is an absence, and in a household where somebody has asthma an absence is not the same as a zero.

Sources

Figures were read on the dates shown against each source. If one has changed, or if we have got something wrong, tell us and we will correct the page.