If you’re an allergy or asthma sufferer, having an air purifier in the home can be one of the most beneficial ways to keep your air clean and free from nasty particles that can exacerbate your problems.

Rabbit Air BioGS 2.0 Ultra Quiet HEPA Air Purifier (SPA-550A White)

Rabbit Air BioGS

There are so many air purifiers on the market right now though, it can be tough to choose the right one for you. How do you know which is the best? How do you know which one will work best for you personally?

We’ve taken two of the best purifiers on the market at the moment and put them to the test to see which you should be spending your cash on. Will the Rabbit Air BioGS or Coway Airmega 400 come out on top? Read on to find out.

Initial thoughts

Both Rabbit and Coway are fantastic brands, who promise only the best from their products. Whilst most Air Purifiers have a lot in common, it’s the differences that can be the biggest factor in making sure you get the purest air you can.

Coway Airmega 400 Smart Air Purifier with 1,560 sq. ft. Coverage

Coway Airmega 400

Let’s take a look at the basics of each product.

First up is the Rabbit Air BioGS. With dimensions of 16.6 x 9.8 x 22.2 inches and a weight of 16.8lbs, the Rabbit is a portable machine that can be placed in most areas of the home easily.

In comparison to this, the Coway has dimensions of 14.8 x 14.8 x 22.8 inches and weighs in at 24.7lbs. Whilst both machines are fairly similar in terms of size, the Coway is the heavier and less portable option, meaning that those with any problems relating to lifting heavier items should take care.

Purifying your space

When choosing your purifier, it’s certainly beneficial to keep your home and the space you want to purify in mind.

Rabbit Air BioGS Air Purifier

Rabbit Air BioGS

The Rabbit can purify up to 550sq feet at a time, and it does so twice an hour, making sure you get the best quality air as often as possible. In comparison though, the Coway can purify an area of up to 1,560sq feet twice an hour, meaning that even though there’s hardly any difference in terms of size, the Coway certainly packs a bigger punch.

Filtered for your health

One of the features that stands out the most when it comes to choosing the right Air Purifier for you has to be its filter usage. The better the filter, the better you air quality will be once the purifier has finished its job.

The Rabbit relies on BioGS HEPA Filtration, which boasts 4 stages of purification as well as deoderization and makes it the perfect choice for your home.

Stage 1 contains the pre-filter, which is both washable and permanent and promises to capture all larger sized particles. Stage 2 is the BioGS HEPA Filter, which traps airborne particles down to 0.3 microns in size and reduces common allergens in the air, supporting and prolonging filter efficiency and life.

Stage 3 is a Charcoal-Based Activated Carbon Filter, perfect for reducing household odors. Finally, stage 4 is the Negative Ion Generator which freshens and fortifies the air produced in your home.

Coway Airmega 400 Air Purifier

Coway Airmega 400

In comparison, the Coway relies on its Max2 filter – a combination of activated carbon as well as a True HEPA filter, which traps and reduces up to 99.97% of particles as small as 0.3 microns from the air.

It also promises to reduce more than 99% of volatile organic compounds and fumes in the air to make your air more sustainable and breathable. The Coway also comes with a washable and permanent pre-filter which helps catch those larger particles efficiently.

Fan speeds

The beauty of these air purifiers are that they don’t disturb your everyday or evening routines due to their clever fan modes.

Rabbit Air BioGS Air Purifier Review

Rabbit Air BioGS

The Rabbit is equipped with an ultra-quiet BLDC motor, which operates at five different speeds. At its lowest fan speed, its virtually silent, which means a quiet and peaceful environment is always available. At its highest speed, you know that you’re getting the best quality air from your Rabbit purifier.

Similarly, the Coway Airmega also has five fan modes, and at its two lowest speeds, it’s also virtually silent.

Also, with a clever ‘smart’ mode of fan, you can rest assured knowing that this air purifier is adapting to its surroundings and keeping your air as pure as can be. The fan speed will automatically adjust based on the room’s air quality and lighting conditions, helping to improve your air quality without you having to lift a finger.

Special features

Although both purifiers are fantastic, the Coway definitely creeps up on the Rabbit based on its better range of extras.

Coway Airmega 400 Air Purifier Review

Coway Airmega 400

Unlike the Rabbit Air BioGS, the Coway AirMega is compatible with Amazon’s Alexa’s voice control option, giving you the ultimate ease of use. With voice control options available, it takes the hassle away and gives you more freedom to turn it on wherever you are.

That’s not all though, because the Coway Airmega also includes a pollution sensor, which communicates indoor air quality in real-time. With its brightly colored LED ring, you’ll always be in the know about how clean or dirty your home’s air is, and can manage it accordingly.

Rabbit Air BioGS 2.0 Ultra Quiet HEPA Air Purifier

Rabbit Air BioGS


Whilst the Coway may be the heavier option, and its filtration system isn’t as advanced, it certainly struck us as being the better of the two devices, due to its larger area capabilities as well as the added extras such as compatibility with Amazon’s Alexa, its pollution sensor, and the ability to self-adjust its fan speed based on the air purity.

For these reasons, the Coway Airmega 400 takes the crown and makes the better choice of air purifier. We think that this air purifier is worth every penny to keep your home fresh and free from nasty allergen particles.

Coway Airmega 400

Recommended Affordable Air Purifiers
Best of the Best! Budget Pick Also Great
Coway Airmega 300 Smart Air Purifier with 1,256 sq. ft. Coverage Germ Guardian True HEPA Filter Air Purifier for Home, Office, Bedrooms, Filters Allergies, Pollen, Smoke, Dust, Pet Dander, UV-C Sanitizer Eliminates Germs, Mold, Odors, Quiet 22 inch 3-in-1 AC4825 Coway AP-1512HH Mighty Air Purifier with True HEPA and Eco Mode in White
Coway Airmega 300 Germ Guardian AC4825 Coway AP-1512HH
1,256 sq. ft. Coverage
True HEPA filter
167 sq. ft. Coverage
True HEPA filter
361 sq. ft. Coverage
True HEPA filter
300 Dust | 340 Pollen | 310 Smoke
118 Dust | 125 Pollen | 108 Smoke
246 Dust | 240 Pollen | 233 Smoke

Newsletter Signup

The Best of SmartSmarterSmartest in Your Inbox!

We’d love to stay in touch, sign up for the SmartSmarterSmartest team to contact you with great news, content and offers.