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Smart Air S air purifier review

Updated on December 3, 2023
Written by
Teddy Booth
Teddy joined HouseFresh in 2019 as a senior content producer, producing written content as well as product photography and YouTube videos. He supports Danny as a product tester and is our lead how-to writer.

Our verdict

The guys at Smart Air promise a lot with the Smart Air S, and they really deliver. We believe this is one of the best budget air purifiers available in 2023. 

It provides significant CADR power per $ and with its efficiency and fairly priced filters, it will save you a ton of money after just a few years of usage. 

Starting in 2013, they may not have the marketing polish that you see with Alen, IQAir, or Blueair, but they have what matters when it comes to cleaning the air in your home. 

It’s got no smart or auto mode and only 3 power options but it can clean air much more economically than any of its rivals thanks to its use of an H12 filter and efficient fan.

Smart Air, the creators of the Smart Air S (or The Sqair Air Purifier, as it’s known in the UK), has an interesting backstory. Back in 2013, the founder, Thomas, was working on his PhD in Beijing and affected by the terrible outdoor pollution, he looked into the air purifier market to see what was available. He was shocked by the price of airfier

purifiers, so he decided to create his own DIY purifier that could clean the air using just a fan and a filter

Realizing the potential, Thomas got together with some friends to start his own company focusing on no-nonsense, affordable air purifiers. Since then, they have developed several units that aim to perform well without the high price that most competitive air purifiers come with.

This Smart Air S air purifier is fairly new to the market and was made available to buy in the US in 2020, but has recently become available on Amazon.

  1. In our home lab of 728 cubic ft, we light an incense stick to generate particle pollution and VOCs.
  2. We set up our trusted Purpleair Indoor Sensor with the latest Bosch gas sensor to track levels of PM1ug/m3, PM2.5ug/m3 and PM10ug/m3 and VOCs in the air.
  3. We switch the air purifier to its highest speed and measure how long it takes to get our room air quality down to PM1 level to 0.
  4. We use an energy meter to measure precisely how much electricity is used when running the unit at the lowest and highest fan speed settings.
    enery meter
  5. We track sound levels emitted by the air purifier at different fan speeds with the help of a commercial sound meter.
    sound meter

This review was written AFTER we conducted all these tests. You can rest assured we didn’t just grab some numbers off an Amazon listing or the Smart Air’s website like most other review sites would.

Right, enough with the intro.

The lowdown on the Smart Air S

“For those wanting to clean the air in their home on a budget, the Smart Air S is up there with the Levoit 400S and the TaoTronics AP003.”
— Danny Ashton, HouseFresh Founder & Senior Writer

So you’re a skimmer. Who needs to read the whole thing when we’ve made a nice light pros and cons section for you to peruse, right? Right.

What we really like

The position they take: other air purifier manufacturers have been selling overpriced machines for years
A CADR of 185 CFM for a very fair price that competes well with other good budget brands like the Levoit Core series
I like that it’s pure HEPA and doesn’t have an ionizer
The long-term cost savings are great for both electricity usage and filter replacements
It looks very stylish from an interior design perspective

What we think could be better

No auto function, which is common in similarly priced units like the Levoit 400S
No timer function
Readers have reported they had some issues with customer support in the U.S., but that should now be less of an issue as you can buy your Smart Air S directly through

The specifications

This particular model is Smart Air’s mid-range unit costing $179* but with a CADR of 315 m3/h or 185 CFM, which is similar to that of the Honeywell HPA200 (200 CFM) and Levoit Core 400S (250CFM.)

HouseFresh Rating:★★★☆☆
Time to clean our test room:50 minutes
Air purifier technology:H12 HEPA and optional activated charcoal filter
Recommended room size:430 sq. ft. 
Clean air delivery rate (CADR):185 CFM (315 m³/h)
Dimensions (in inches / in cm):13H x 13W x 14.3D inches (33.02H x 33.02W x 36.32D cm)
Weight (in pounds / in kg):10.1 lbs (4.58 kg)
Noise level (low – high):23 – 52dB
Filter life:6 months
Manufacturer’s warranty1 year
Estimated energy consumption:$45.20 per year

Elegant design that will stand out for the right reasons

“Oh wow… This one is cute!”

That was the first thing my wife said when I showed her this unit. 

She is not normally so positive about the many air purifiers I bring to our home, so this was a good sign.

And I must say, it’s one of the better-looking units on the market as it doesn’t look too industrial. Due to its fairly small size, it doesn’t take up too much space and could easily fit in with a well-designed trendy living room.

I placed it next to a very popular model we have with a similar spec sheet to the Smart Air S, the Levoit LV-PUR131 to take in the difference in design. 

Undoubtedly, this little unit looks a hell of a lot better than your “normal” air purifier. Its cute, fat body and Beachwood legs blend into the room instead of looking like something you would find in a science lab.

The Smart Air S comes in a fairly small box and is well-packaged, with the power supply unit sitting on top.

The feet are neatly packed separately and must be screwed on before switching the unit on. 

I did have one minor build quality issue. One of the screws had become loose, and I needed to re-screw it before securing the final leg. It’s minor, but something I would want to make the team at Smart Air aware of.

Simple but not smart

You don’t get much simpler than this for an air purifier, with 3-speed settings controlled by one circular rotating switch in the middle. That’s it.

If you are looking for smart features, this is not your unit. I personally like the simplicity, and there was also no remote for one of my toddlers to steal!

The team at Smart Air thinks auto-features are a waste of time for the most part, and while I agree to some extent, I know some people do like the option of using a timer or auto mode for minor pollutant issues.

Energy saving filtration

This air purifier is one of the simplest units I have come across. As you can see in the video below, it’s simply a large fan combined with a HEPA filter housed in plastic. 

An interesting factor of this unit is that it uses an H12-type HEPA rather than the trendier medical grade H13 HEPA (although you can now choose a H13 for the Smart Air S but it will reduce airflow.)

The team at SmartFilters makes the point that H12 allows more air to pass through, allowing it to clean the air – without requiring the amount of electricity needed for a stronger grade HEPA filter.

As with many new HEPA filters, it arrived wrapped in plastic packaging, so needed to be removed before switching it on. Whilst this is clear in the manual, it would be good to see a more prominent warning. 

Dyson uses a yellow and black one to make sure no one uses the unit with the filter in the plastic wrap (it happens more often than you would expect!)

Supercharging your Smart Air S with an activated carbon filter

There is an option of getting an activated carbon filter that works with the H12 HEPA for an extra $29.99. You can purchase the filter after you’ve bought the unit like I did.

You’ve probably heard the term Activated Carbon or Activated Charcoal Filter before. This is where a filter is packed with either loose or bonded carbon which absorbs VOCs (a.k.a. Volatile Organic Compounds – a.k.a. “bad stuff”) in the air, trapping them so clean, odor-free air can be released back into your room.

Installing the Activated Carbon Filter to your unit is so easy. There are no fiddly, twisty mechanics or screws to find the right tool for. Just 3 easy steps:

STEP 1: Turn upside down and remove the bottom of the unit by pressing in the sides and lifting.

STEP 2: Place the filter into the unit (don’t force it, it will sit comfortably)

STEP 3: Put the bottom back on and turn the right way round.

Told you it was easy. Want to get one for your Smart Air S too? Here you go:

Smart Air S Carbon Filter - Air Filter Replacement For Smart Air Model S Air Purifier - Helps Eliminate Odors, Smoke, VOCs & Airborne Particles - 1 Count
  • COMPATIBLE WITH SMART AIR S: Replacement Carbon air purifier filter for Smart Air S air cleaner.
  • BREATHE CLEAN AIR: Take a breath of fresh air! Our Carbon air filters help eliminate: odors, smoke, VOCs and other airborne particles.
  • PERFECT FOR: Homes with recent renovations or repainting, smoke odors, or near a source of pollution.
  • REPLACEMENT: Suggest replacing the filter every 6-12 months.
  • HIGH-QUALITY: Our high-quality Carbon air filter pairs with Smart Air S (ASIN: B08ZJTRQDM).

The Smart Air S cleared our test room in 50 minutes

I tested this unit in the test room (728 cubic ft), which is a fairly small home office. I used incense to create airborne pollutants and then used a Purple Air indoor sensor to track how these pollutants reduce over time.

The Smart Air S was able to remove all the PM1 pollutants in 50 minutes.

Air cleaning performance test results

Let’s put these results into perspective by comparing the Smart Air S to other units that clear similar-sized rooms, as well as the top 3 best-performing air purifiers we have tested:

This performance was very impressive, especially as it got close to the IQAir Healthpro Plus in sheer cleaning performance! Let’s keep in mind that the IQAir Healthpro Plus is a $1000 unit that comes with a large activated charcoal filter, so it would deal with VOCs and chemicals more effectively than the Smart Air S, but it’s still impressive.

Noise levels test results

As you can hear from the video, the sound the Smart Air S emits is not overwhelming, but also not the quietest unit we’ve tested.

In fact, when you compare it to other units, it’s perfectly average. Yes, you’re going to hear it when it’s on full power, but it’s not going to command the whole room.

The cost to run a Smart Air S: $105.20 per tear

1. Electricity costs = $45.20

The costs of running air purifiers are something that gets overlooked but it’s an important factor to consider, especially if you’ll be using this unit regularly. 

As always, I tested the Smart Air S with my trusty power meter.

  • Power 1 – 6.4 Watts
  • Power 2 – 18.9 Watts
  • Power 3 – 42.6 Watts
Smart Air SIQAir Healthpro 
Cost per year*$54$208
Energy used per year (CADR)141290

*If you ran the unit for 24hrs a day. 

The team at Smart Air has created something very special with the Smart Air S, a good looking air purifier with a decent CADR that also manages to use less energy than the entry model of a popular competitor. 

The energy savings might be down to the fact that the Smart Air S uses a H12 filter instead of a H13, no-pre filter, and (what I assume to be) a more efficient fan.

2. Filter costs = $60

Another long-term cost to consider is filter replacement. With mechanical filter technology like HEPA, the filters get full of pollutants and need to be replaced regularly.

The Smart Air S has filters available for $29.99, and they suggest replacing them every 6 months. Running a Smart Air S will cost you $60 per year on HEPA filters alone. In comparison, the Levoit 300 has filters available for $50 that also need replacing every 6 months, so costs $100 per year. 

Smart Air S HEPA Filter - Air Filter Replacement For Smart Air S Air Purifier - 1 Count
Smart Air S Carbon Filter - Air Filter Replacement For Smart Air Model S Air Purifier - Helps Eliminate Odors, Smoke, VOCs & Airborne Particles - 1 Count
Smart Health S HEPA Filter
Smart Health S Activated Carbon Filter
More information
Smart Air S HEPA Filter - Air Filter Replacement For Smart Air S Air Purifier - 1 Count
Smart Health S HEPA Filter
More information
Smart Air S Carbon Filter - Air Filter Replacement For Smart Air Model S Air Purifier - Helps Eliminate Odors, Smoke, VOCs & Airborne Particles - 1 Count
Smart Health S Activated Carbon Filter
More information

Bottom line 

Smart Air is a brand on a mission and with the Smart Air S, they’re showing us they mean business. 

By taking a simplistic approach to air purification, they have managed to achieve amazing air cleaning performance without the energy and filter replacement costs you find with competitors. 

For those wanting to clean the air in their home on a budget, the Smart Air S is up there with the Levoit 400S for units that I would recommend in 2023.

I patiently await the release on for the larger Smart Air units, such as the Blast Mini and Blast Mk 2 to see if they provide the same superb level of air purification performance, which would make them a perfect alternative to the IQAir Healthpro plus as a pure HEPA whole house air purifier.


We used the Department of Energy’s appliance energy calculator to calculate yearly costs associated with running the Smart Air S for 24hs a day for 365 days. We chose to run this calculation utilizing the US average utility rate, which is $0.12/kWh as of February 7th, 2023.

At HouseFresh, we have been reviewing air quality products since 2010. In all these years, we learned not to rely on manufacturers’ claims and the ever-so-glowing marketing materials. That is why we buy products with our own money, so we can write unbiased reviews after we’ve had enough time to evaluate air quality products in our home lab. Every unit we recommend has been thoroughly tested to assess its performance, energy consumption, and noise levels emitted in real-life environments. If you have any questions about our testing process for different types of air quality products, just drop us an email at

Last update on 2023-12-03 / Affiliate links / Images from Amazon Product Advertising API

About the author

Teddy Booth

Teddy joined HouseFresh in 2019 as a senior content producer, producing written content as well as product photography and YouTube videos. He supports Danny as a product tester and is our lead how-to writer.