Alen BreatheSmart 45i Air Purifier: Trusted Review & Specs

Following a couple of years off, Alen has brought back the new FLEX (with a new name of Alen BreatheSmart 45i) – but things are markedly different compared to the air purifier which was first introduced in 2017. Alen has added some premium features, better room coverage and robust air filtration into this mid-range device. But with such lofty promises, is it destined to trip up? Let’s find out in our today Alen BreatheSmart 45i Review.

Alen BreatheSmart 45i ranks B- in our air purifier ranking list. We give the biggest and most thorough database of air purifier reviews in the world.

The Alen today flagship is the brand new Alen BreatheSmart 75i.

In Breathe Quality, we have reviewed all air purifiers under these sections. Also, we guarantee that:

  • We do give honest reviews (both pros and cons) so anyone will guarantee to have the wisest choices.
  • We do not (and never) exaggerate one product just to let you click the links and buy that product blindly.


alen breathesmart 45i review

  • Customizable color options
  • Large room coverage
  • Lifetime Warranty

  • Still low CADR rating for room coverage
  • Lack certain smart features

Alen is gradually and steadily becoming a well-known expert in American air purifier market. By the end of last year, they released not one, but two flagship devices to strike from mid-range to high-range segment. Yes, even the cheaper Alen BreatheSmart 45i is at least $100 more than the older Alen BreatheSmart FLEX, which is hardly budget. But it quickly turns out to be the best all-round Alen air purifier for the mid-range. Today, I am happy to introduce our Alen BreatheSmart 45i Review.

Alen BreatheSmart 45i Price

To the Alen fan who wants to stick with the brand though, the Alen BreatheSmart 45i offers a much cheaper way to get a 2018 model without having to pay the sky-high prices of the Alen BreatheSmart 75i, without sacrificing too much in terms of performance – and with a cheeky amount more features than one might expect.

While it’s impossible to know for certain what Alen is aiming to achieve with the later launch of the Alen BreatheSmart 45i, the fact remains that it’s already enjoyed the buzz of the new flagship BreatheSmart 75i launch, and now has a second bite of the budget air purifier with lifetime warranty.

Well, Alen has pulled a marketing masterstroke, but I must admit that this Alen BreatheSmart 45i is nothing like the cheap low-range devices. You can now buy the air purifier in the local Alen stores, starting from $429 for the White version, adding a HEPA-Pure air filter. Any customized color version plus the HEPA-OdorCell air filter will cost you no less than $498. This price tag, like I stated earlier, is at least $100 more than the Alen BreatheSmart FLEX. Considering the Alen BreatheSmart 45i keep the same appearance and air filtration, you may wonder why there is a different in the cost. Don’t worry, I will explain later, but one promise, it is truly better.

With that pricing, the Alen BreatheSmart 45i targets the same segment of the market as the stellar GermGuardian AC9200WCA, Vornado PCO575DC, TruSens Z-3000 and Rabbit Air BioGS 2.0. The Oransi Max is also a worthy challenger if looking at the huge fan base in Twitter of the brand. However, with an exceptional customer service and community behind, the Alen BreatheSmart 45i has enough trick up its sleeve to head on any opponents at the moment.

We also notice the presence of the Dyson Pure Cool Tower and Dyson Pure Cool Link in the same price range. These air purifiers, besides the True HEPA filter, are having an amazing cooling fan power to help you survive the summer time. The Dyson Pure Hot+Cool, with a little bit higher cost, will come with the heating power as well.

Top Alen BreatheSmart 45i deals right now

Alen BreatheSmart 45i HEPA Air Purifier with Pure Filter for Allergies and Dust.

“I’ve been using Alen Air to purify the air in my home for 9 years. The products work great and their customer service is even better” – said an Alen testimonial. White Edition.

Related post: Best air purifier 2024.

Alen BreatheSmart 45i Design and Size

Compared to the Alen BreatheSmart FLEX, the Alen BreatheSmart 45i upgraded in a number of ways to hit that new higher price point. That said, there are a number of key features that are the same, and the design of this air purifier is totally the same. To the untrained eye, or someone not using the Alen BreatheSmart 45i and FLEX side by side, it might even be hard to instantly tell the two apart – but there are some key differences that we need to dig into.

It follows the edge-to-edge look of the FLEX, with a metal body standing in 25-inch height. Other specs for size remain the same, with 15 inches in width and 8.5 inches in depth. Even for the weight, Alen BreatheSmart 45i keeps the same 15 lbs, and with an unique Alen’s handle, you can easily move this air purifier anywhere in your home without problem.

The panel, as mentioned, is still covering the same air intake grill behind. Alen truly commits in the bottom-to-top air flow system for all members of BreatheSmart family. This air flow system concept is typical among the mid-range devices, like what is in vein of Blueair Classic 205 to Rabbit Air BioGS 2.0 and GermGuardian AC9200WCA.

The rear of the air purifier isn’t the same size as the FLEX, with a much smaller air output grill. But looking at the actual size of the grill and the fan power inside the Alen BreatheSmart 45i, it appears the performance stay the same after all.

Another difference is the new control panel on top of this Alen BreatheSmart 45i, which is full 7 function buttons. To differentiate this air purifier with others in the same brand, you should notice the word “Alen BreatheSmart 45i” on the control panel.

alen breathesmart 45i review


Being able to pick up this air purifier in a variety of colors makes it a bit more interesting. There are 14 other color options to choose, from: marble, red, gold, silver, espresso, rosewood, maple, oak, bronze, stainless, black, gray and graphite. For those who want something a bit more conservative, there is also white option. The range of colors is great and there isn’t one that stands out as looking ugly: they’re all colored well and each reacts a bit differently when light hits its front panel.

Related post: Best air purifiers for bedroom.

Alen BreatheSmart 45i Filters

The feature most people have been concerned about with the Alen BreatheSmart 45i. It is reasonable because by default we look at the quantity and the quality of its air filters, and what the air filter types are using to decide the performance of this air purifier. Not so much from the FLEX because of the same HEPA air filter, with 4 different types as below.

  1. HEPA-Pure – The standard HEPA filter of Alen BreatheSmart 45i, which is able to capture 99% of as small as 0.3 microns pollutant particles such as dust, dust mites and pollen.
  2. HEPA-Fresh – The next level HEPA filter will improve the first HEPA-Pure, with an addition of Activated Carbon filter, to deal with the household odors like cooking smells and light smoke. This air filter is necessary for people who are sensitive to VOCs.
  3. HEPA-Silver – For a little bit more money, you can upgrade to the HEPA-Silver filter with anti-microbial Silver-Ion threads that prevents the growth of mold spores and bacteria.
  4. HEPA-OdorCell – The ultimate level HEPA filter of Alen BreatheSmart 45i, with the unique Alen’s Molecular Conversion Powder, that can destroy the odors on a molecular level.

The Alen BreatheSmart 45i uses a pre-filter to capture the large objects of pollutants. This gives a decent capture of something like pet hair or large dust, which is also capable of prolonging the lifetime of HEPA filter. The pre-filter is nothing like the Honeywell HEPA air purifiers, and can be washable for unlimited using.

But a noteworthy change from the Alen BreatheSmart FLEX is the return of the ionizer, which is not good enough in the old models. However, the story is different, as there is not one negative review about the ionizer making crackling noise or irritating asthma anymore. I measured an amount of 0.001 ppm (parts-per-million) ozone emission, which is 50 times less than the standard 0.05 ppm for safety.

Alen BreatheSmart 45i now uses the certified True HEPA filter, supported with an ionic feature to improve the performance. In practice, I put both the Alen BreatheSmart 45i and the old Alen BreatheSmart FLEX into a test with more perfect testing samples for the price – the GermGuardian AC9200WCA. The testing conditions are the same, running in 1 hour for a room coverage of 200 square feet. They both had the same high efficiency of trapping 99.92% of all airborne particles down to 0.3 microns. However, both air purifiers were lower performance than the Blueair Classic 280i and Medify MA-40.

alen breathesmart 45i review

Only one downside, the Alen BreatheSmart 45i’s air filter will cost you from $59 for HEPA-Pure, and up to $89 for HEPA-OdorCell air filter. The highest cost is $10 more than the True HEPA filter from GermGuardian AC9200WCA. You need to change the air filter after 6 months to 1 year, depending on the frequency of using.

Related post: Best air purifiers for allergies.

Alen BreatheSmart 45i Room Coverage

We won’t beat around the bush here. The Alen BreatheSmart 45i can mostly back up one of Alen’s big claims: all BreatheSmart air purifiers offer the best room coverage for any house. Of course, your mileage will vary with any device, but I’m really impressed to see all the little tricks offered by the Alen BreatheSmart 45i. It can cover a room of 800 square feet, and the lowest room coverage is just 250 square feet.

The ACH of Alen BreatheSmart 45i is 2X to 5X. For the best performance, the Alen BreatheSmart 45i can clean your room 5 times per hour.

The CADR of Alen BreatheSmart 45i is 208 Dust/ 194 Smoke/ 230 Pollen (cfm). Alen completed the air flow management in this Alen BreatheSmart 45i, so this air purifier will be capable of dealing with large rooms even with such low CADR rating.

Related post: Best large room air purifiers.

Alen BreatheSmart 45i Sound

One reason Alen gave to public for not having True HEPA filter is because they don’t want the True HEPA filter restricts airflow. It is quite reasonable, and with less restriction in the air flow, you don’t need a powerful fan to cover a large space. But now with the real True HEPA filter, is the statement going to be true?

alen breathesmart flex review


If you’re any kind of seasoned Alen users, you probably won’t be that impressed by the noise level of 39 decibels at the lowest setting of Alen BreatheSmart 45i. That’s not to say it’s not decent – it’s silent as the noise level of the library, but it doesn’t really break through any records in the market, if compared to the Rabbit Air BioGS 2.0.

At the highest setting, the noise level remains the same with Alen BreatheSmart FLEX, just only 55 decibels (db). The noise level is still higher than the normal conversation at home, but you will be pleased to use it, mostly because of the pink noise. For someone who don’t know, the pink noise, like white noise, consists of varying frequencies, but the volume (in decibels, or dB) decreases whenever the frequency doubles. This results in a more balanced noise compared to the harsh contrasts of pure white noise. It has helped sleepers improve their sleep onset and their sleep maintenance.

That’s why the Alen BreatheSmart 45i is truly a device for bedroom. Even if you are trying to run this air purifier in quiet places like the office, it is a great idea.

Related post: Best air purifiers for baby.

Alen BreatheSmart 45i Power Consumption

One of our most FAQs is “Do air purifiers use a lot of energy?” An air purifier is meant to run for a long time to be efficient, that’s why many air purifier brands consider the energy-saving standard, mostly in the rate of Energy Star, is one important selling point.

The power consumption of the Alen BreatheSmart 45i reduces to 38W from the previous 56 watts of BreatheSmart FLEX, on the highest speed. It’s hard to definitively state why the power consumption is so much better on this Alen BreatheSmart 45i than any other Alen devices I’ve tested, as there aren’t that many changes that should make a difference. Compare to the 80 watts from Blueair Classic 205 and 70 watts from GermGuardian AC9200WCA, the Alen BreatheSmart 45i will truly save your energy.

With such huge improvement in keeping low power consumption, the Alen BreatheSmart 45i deserves the Energy Star rating than any members in the same family. This symbol is also the main selling point to get one air purifier.

For using a Alen BreatheSmart 45i 8 hours per day, it would cost you about $14 per year.

Related post: Best air purifiers for pets.

Alen BreatheSmart 45i Additional Features

But again, why you should buy the Alen BreatheSmart 45i? Better performance than the Alen BreatheSmart FLEX (and even the Alen BreatheSmart FIT50 before that)? The lower power consumption? They are all true, but you are not convinced to give out more than $100 for new air purifier, right?

Then you should know that if you truly want a Smart air purifier (look at the name, it is BreatheSmart), you should buy the Alen BreatheSmart 45i. It is the cheapest device from this brand with an accurate Smart Sensor, a must-have additional feature for every high-end air purifier. The sensor will detect the actual air quality in your room, and then it notifies you the status of the air quality around you with the light in the control panel, with red being the most emergency case. Moreover, the Auto Mode will be activated to change the fan speed of the air purifier to meet the air quality’s need. And when it’s bedtime, lights-off mode cleans the air without disturbing your sleep.

There is no need to tell you, but you still have an Advanced Timer to control the Alen BreatheSmart 45i, with options varied from 2 hours, 4 hours and 12 hours. Also, you have a LED indicator for filter replacement. Now, you don’t need to remember the date to change your air filter anymore.

Related posts:

1, Best air purifiers for smoke.

2, Best air purifiers for dust.

3, Best air purifiers for mold.

Alen BreatheSmart 45i Customer Service

Running through a very long review about Alen air purifiers, you may question us: “Why I need to buy Alen air purifier?” Yes, if it is not for the outstanding performance, or the top-class fan power, then there is must be something really, really important. What I’m trying to say here is the perfect customer service from the Alen Corporation.

Alen doesn’t hide the intent to speak high of their customer services. Look at their website, there are full of content to support the customers. You will have their phone, their emails, and of course, their support policies without any hindrance. To reach the Alen, you can contact them 6/7 days per week. They provide the best fast and free shipping for any products, as long as the orders are placed before 3 PM, they will guarantee to ship in the same day. Impressive, right?

They expand the refund time up to 60 days, or 2 months. You won’t need to worry about the quality of your air purifiers, because Alen will back you up with (also the first) Lifetime Warranty. Whenever your personal Alen air purifier doesn’t operate as normal, you will have a same refurbished air purifier with free shipping. To do this, please call 512-436-0457.

There are a lot of good review for the Alen customer services, that’s why I highly recommend to look for the brand if you need permanent better air quality for your home.

Top Alen BreatheSmart 45i deals right now

Alen BreatheSmart 45i HEPA Air Purifier with Pure Filter for Allergies and Dust.

“I’ve been using Alen Air to purify the air in my home for 9 years. The products work great and their customer service is even better” – said an Alen testimonial. White Edition.

Our verdict

Alen BreatheSmart 45i is necessary to replace both the Alen BreatheSmart FLEX and Alen BreatheSmart FIT50 to be the best budget Smart air purifier from this brand. The performance/value of this device is truly the reason why it is the most pursuit. It now comes with a True HEPA air filter, and one step closer to the flagship – the Alen BreatheSmart 75i.

Alen BreatheSmart 45i Air Purifier: Trusted Review in 2024
Alen BreatheSmart 45i Air Purifier: Trusted Review & Specs

Alen BreatheSmart 45i Reviews and Specs (Air Purifier Trusted Reviews in 2024). ✓ Cleaning Power: HEPA ✓ Lifetime Warranty ✓ Value: 3.7/5 ✓Certified Review.

Product Brand: Alen

Product Currency: USD

Product Price: 429

Product In-Stock:

Editor's Rating:
  • Performance
  • Features
  • Annual Cost
  • Design
  • Price


The Alen BreatheSmart 45i, along with the Alen BreatheSmart 75i, is its best air purifier at the moment.