Where to buy: the Mighty is $154.99 in white at Amazon, marked down from $229.99, and $154.99 in black. It is $239.99 at Coway. The genuine filter set is $59.79 at Amazon and at Coway.

• What size room is the Coway Mighty for?
• Is it AHAM certified, and what is its CADR?
• Does it have an ionizer, and how do you turn it off?
• How quiet is the Coway Mighty?
• Mighty vs Mighty2 vs MightyS vs 200M: which one to buy
• How often to change the filter, and what it costs
• Is it good for allergies, asthma, pets and odors?
• Common problems and cons
• Levoit or Coway: which is better?
• Questions people ask

What size room is the Coway Mighty for?

A bedroom, or a living room up to 361 square feet.

Get the tape measure out before you order. Multiply the length of the floor by its width, and if the answer is 361 or less, the Mighty is big enough for the room.

Our air purifier size guide goes through it room by room, if you are torn between two sizes.

Ignore the “up to 1,748” in the Amazon title, and buy by the 361. The bigger number is real, but it is a room the Mighty gets through only once an hour.

In the right size room, it is an easy purifier to live with. It sets its own speed, you can switch its colored light off at bedtime, and the chore you will do most is rinsing the pre-filter.

Is the Coway AP-1512HH AHAM certified, and what is its CADR?

No. The 361 square feet is Coway’s own figure, and I would still buy by it.

The Levoit Vital 200S and Core 300 are certified by AHAM, and the Mighty is not. If you want a certified number for a room this size, buy the Levoit Vital 200S.

The CADR is a purifier’s clean air number, and Coway puts the Mighty’s at 233 for smoke. AHAM’s own math turns 233 into a room of 361 square feet, the same size Coway gives it, so I trust the figure. Just do not stretch it to a bigger room.

Does the Coway Mighty have an ionizer, and how do you turn it off?

Yes. One press of the IONIZER button turns it off, and a light shows you whether it is on.

Check that light when you first plug the purifier in, so you know which way it is set.

Keep it to a quick press. Holding the same button for 3 seconds switches the air quality light instead.

For a bedroom, I would keep it switched off. The ionizer is why California lists the Mighty among purifiers that may give off some ozone. It has been tested to stay under the state’s limit, and I would still rather sleep without it.

The 200M has an ionizer too, with the same button. The Mighty2 and the MightyS have none. They clean the air with their filters alone, and on California’s list they make no ozone or ions.

How quiet is the Coway Mighty?

Quiet on its lowest speed, and in eco mode the fan stops by itself once the air has stayed clean for half an hour.

It is not silent. It makes a steady fan sound, and on its lowest setting it is easy to sleep beside. If you already keep a fan running at night, you will be used to it.

For a quieter night, press the speed button until you reach eco.

During the day, leave it on auto. It moves between speeds 1, 2 and 3 on its own, going by what its dust sensor picks up.

It is at its loudest on 3, so save that speed for when you are out of the room.

At bedtime, switch off the colored light, and set the timer if you only want it running while you fall asleep.

Coway Mighty vs Mighty2 vs MightyS vs 200M: which one should you buy?

Buy the plain Mighty, the AP-1512HH, at Amazon.

It is under $155 there, in white or black, more than $80 less than Coway charges. Both colors are the same purifier, so pick the one that looks right in your room.

Amazon sells and ships both itself, so there is no marketplace seller in the middle.

Buy the Mighty if

• It is going in a bedroom or a living room up to 361 square feet.
• You want it to set its own speed, and to rest the fan in eco mode once the air is clean.
• You want to spend the least.

16.8 x 18.3 x 9.6 in12.3 lb24 to 53 dB, Coway’s figuresAuto mode with a dust sensor3 speeds plus eco modeTimer 1, 4 or 8 hoursIonizer with an on/off buttonWashable pre-filterNo Wi-Fi3-year warranty on motor and electronicsWhite or black

Coway Mighty vs Mighty2

Pay more for the Mighty2 only if you want it to go into sleep mode by itself when you turn the light out, or you want no ionizer in the house. For the bedroom itself, the plain Mighty with eco mode and the timer does the job for less.

Its light sensor makes the switch once the room has been dark for 3 minutes. On its lowest speed, it is the quieter of the two.

It runs on one main filter that you change once a year, where the Mighty has two on different schedules.

Press a button and it shows you how much fine dust is in the air, which is nice if you like to see the purifier working. Its timer runs up to 12 hours, long enough for a whole night, and it has a mute setting.

It costs over $110 more, at under $270. It is also 2.9 pounds heavier, which you will notice if you carry it from room to room.

Coway Mighty vs MightyS

Skip the MightyS unless you want to run the purifier from your phone. It swaps the ionizer for Wi-Fi, Coway’s IoCare+ app and Alexa.

It is the most expensive of the four, at under $300, and Coway rates it for a slightly smaller room than the Mighty. If the app is not what you are after, the Mighty2 costs less and has no ionizer either.

Coway Mighty vs 200M

Buy the Mighty at Amazon, where the 200M costs over $70 more. The 200M gives you the same filters and ionizer with a newer control panel.

At Coway the prices flip, and the 200M costs a little less than the Mighty. If you are buying there anyway, get the 200M.

How often to change the Coway AP-1512HH filter, and what it costs

Clean the pre-filter every 2 to 4 weeks. Replace the deodorization filter every 6 months and the HEPA filter once a year.

Only the pre-filter washes. Vacuum it or rinse it in the sink, and let it dry all the way before it goes back in. Never wet the two filters behind it.

Coway sells a spare on its own, so you can swap in a dry one while the wet one dries.

The other two wear out at different rates, so write down both replacement months when you set it up. The deodorization filter, which handles smells, runs out first.

Coway bases that schedule on 8 hours a day at top speed. In a home with pets, or one where it runs day and night, look at the filters each time you clean the pre-filter instead of going by the calendar.

The first time you open it up, you will see what it has been pulling out of your air. Expect dust, and pet hair if you have a dog or a cat.

I would buy the genuine set, both filters in one box, for under $60 at Amazon or Coway. Other brands sell sets made to fit it for under $40, but I cannot tell you how well they fit or filter.

If you buy the Mighty2 or the MightyS, each takes its own filter, changed once a year and under $70 at Coway. Buy the one named for your model.

Both still have a washable pre-filter. After you change the Mighty2’s filter, hold its Information button for 3 seconds. Skip that step and its display can show an E3 error.

Is the Coway Mighty good for allergies, asthma, pets and odors?

Yes, in a room its size. In the bedroom, it pulls dust and pollen out of the air the person with allergies breathes all night.

One parent bought a Mighty for a daughter with asthma. “The air quality in her room has improved so much that she’s no longer coughing.”

A dehumidifier was running in there too, so the purifier had help. For a bedroom like hers, I would leave it on auto all night, so it speeds up when the air gets dusty. Eco mode stops the fan once the air has stayed clean for 30 minutes.

With a dog or a cat, the pre-filter catches the hair first. Clean it every 2 weeks, the short end of the range, because a clogged pre-filter slows the air down.

For smells, the deodorization filter does the work. If smells are the reason you are buying it, change that filter on time and do not stretch it.

Common problems and cons of the Coway AP-1512HH

It can give off a chemical or metallic smell, and the air quality light can seem stuck on one color. Run it the day it comes, so you can still return it.

The filters can smell of chemicals or metal. Give it a few days, and send it back if the smell bothers you or your home does not feel any different.

The air quality light can sit on its cleanest reading when the air is not clean, and auto mode can seem slow to react. Start by cleaning the sensor lens.

If the reading still never changes, hold the speed and IONIZER buttons together for 2 seconds to change how sensitive the sensor is. Pick Sensitive if it stays on the cleanest reading, and Insensitive if it stays on the worst.

If the air coming out feels weaker, or a bad smell comes out of the vent, a filter is due. If no air comes out at all, check that the front cover is shut properly.

If something else goes wrong, unplug it and call Coway. The warranty covers the motor and electronics for three years and the other parts inside for one, so call before you pay anyone else to look at it.

Who should skip it

• Skip it for a room bigger than 361 square feet, and buy a purifier rated for the room you have.
• Skip it if you want to run it from your phone. The MightyS does that.

Levoit or Coway: which is better?

Buy the Coway Mighty to spend a little less. Buy the Levoit Vital 200S for a room size AHAM has certified and no ionizer.

They are made for a similar size of room. The Mighty costs a little less at Amazon, under $155 against under $170 for the Vital. I would pick the Mighty if the money matters more to you than the certificate.

The Vital has no ionizer and makes no ozone.

For a home office or a nursery, look smaller, at the Levoit Core 300, which is certified for a room up to 222 square feet. We bought a Core 300-P in April 2021 and put it in our bedroom. It was too small for the room, so we moved it to our home office, which is smaller.

Our reviews of the Levoit Core 300 and the Levoit Vital 200S cover both in full.

Questions people ask

I sold contract-grade furniture from 2016. More about who runs it.