Alen BreatheSmart 75i Review: Arguably #1 Air Purifier In 2024

There are literally 100s of air purifier brands and 1000s of models out there. Arguably, among all these, the Alen BreatheSmart air purifiers are the single best air purifier series on the market.

Alen BreatheSmart 75i is the biggest Alen BreatheSmart air purifier (achieving 2 ACH even in 1,300 sq ft large spaces). This quiet giant is not only considered to be the best Alen BreatheSmart model; according to a spec-by-spec analysis of 529 air purifiers, the Alen BreatheSmart 75i is the best overall air purifier in 2024.

With the 75i model, the question “Is Alen BreatheSmart 75i any good?” is far less relevant than the question that really matters:

What exactly makes Alen BreatheSmart 75i such a superb air purifier?

In this review of Alen BreatheSmart 75i, we will delve deep into every aspect of this air cleaner – from CADR rating, to ACH, superb H13 HEPA filtration system, quiet operation, real-time air quality Smart Sensor, lifetime warranty, and more – to truly see exactly why Alen BreatheSmart 75i is the best air purifier you can buy.

75i air purifier in the living room
Alen BreatheSmart 75i placement in the living room.

You can use these navigation helpers to check anything in particular, like the filtration system, CADR rating, available Alen BreatheSmart 75i sales, and so on:

Alen BreatheSmart 75i Air Purifier Review At-A-Glance: Best-of-the-best air purifier in 2024. Extremely thorough at removing 99.99% down to 0.1-micron air pollutants (dust, pollen, smoke, etc.) thanks to H13 medical-grade HEPA filters; outstanding 400 CADR rating. Powerful (350 CFM), yet energy-efficient (45W), and very silent (49 dB max). The price of 75i is rather high but the 12-month durable air H13 HEPA filters need to be replaced only 1x per year, instead of 3x year (long-term savings outmatch the initial price of the unit).

All in all, words cannot describe the beauty of the specs and the device itself. Alen BreatheSmart 75i is the very pinnacle of air purifier engineering and is justifiable rated the #1 air purifier currently on the market.

Overall rating: 5 out of 5 stars

Overall Alen BreatheSmart 75i Review

  • Ranked #1 air purifier in 2024; no other unit has such elegant design, performance, and easy of operations
  • Outstanding 400 CADR rating; achieved with only 350 CFM airflow
  • Up to 1,300 sq ft coverage (2 ACH) and 520 sq ft coverage for allergy-prone people (5 ACH)
  • The quietest large air purifier; 25 dB at the lowest speed and 49 dB at the highest
  • H13 medical-grade HEPA filters that last for 12 months; 99.99% efficient air cleaning and low maintenance costs
  • An energy-efficient fan (1.8 to 45W) additionally decreases the maintenance costs (lower electricity bill)
  • Smart Sensor technology; neat real-time air quality sensor, with Alen adjusted operation protocol is pure gold
  • Higher initial cost of 75i (well balanced out by long-term savings on HEPA filters)

Alen BreatheSmart 75i Specifications

alen 75i specifications such as cadr rating, ach, airflow, filters, filter lifespan, weight, noise levels
Max. Coverage Area: 1,300 sq ft (2 ACH)

520 sq ft (5 ACH)

CADR Rating: 400
Airflow: 95 CFM (Speed 1), 170 CFM (Speed 2), 240 CFM (Speed 3), 280 CFM (Speed 4), 350 CFM (Turbo Speed)
Filters: True HEPA Pure (H13) – 99.99% 0.1-micron air pollutant capture
Filter Lifespan: 12 Months (Even for 24/7 operation)
Power Output: 1.8 – 45 Watts
Noise Levels: 25 dB to 49 dB
Dimensions: 27″ x 18.5″ x 11.5″
(H x W x D)
Weight: 27 lbs
Price: $$$$
Average Rating: 5 out of 5 stars

Alen BreatheSmart 75i True HEPA Antimicrobial Filtration System

Filters are the heart of air purifiers; this is as true for Alen BreatheSmart 75i as for any other air purifier. While most air purifiers use several layers of generic filters (prefilter, activated carbon filter, HEPA filter is the standard-setting), Alen uses superior all-in-one filters that combine:

  • H13 True HEPA filters. These medical-grade filters remove air particulates that are 3x times smaller (0.1-micron) than what standard H10-H12 HEPA filters can remove. They are also 99.99% efficient; the highest possible HEPA filter efficiency rating.
  • Activated carbon filters. Designed to absorb undesired odors, the activated carbon filter uses charcoal to capture cigarette smells, cooking smells, even diaper smells, and so on.
Here is how Alen BreatheSmart 75i True HEPA filter looks like.

To protect this delicate and high-performance Alen BreatheSmart 75i filter, you have a pre-filter installed before the HEPA-activated carbon filter, to intercept bigger particulates like hair and large dust particles. These air pollutants could clog the main Alen filter; pre-filters (2-pack costs about $20) protect the main filter and prolongs its lifespan to 12-15 months (way above average).

When buying the Alen BreatheSmarth 75i, you will have to choose the main filter that best fits your needs:

Which Main Filter To Choose For 75i? Pure, Fresh, Pet, Heavy Odor Filters

Alen BreatheSmart 75i are unique; they are specifically designed for the 75i unit. All of them have True H13 HEPA filter and are capable of antimicrobial activity. Where they differ is primarily in the activated carbon filter inclusion and size.

Here is a quick guide to the main Alen BreatheSmarth 75i filters:

differences between pure, fresh, pet, and heavy odor filters for alen breathesmarth 75i air purifier

Notice that all 75i main filters are designed to remove allergens, dust, mold, germs, and bacteria. That alone is superb; obviously, the Alen BreatheSmart 75i filters are top-of-the-line.

What is more, however, you can choose a specific filter with additional filtration ‘powers’. For example, the B7-Fresh Alen BreatheSmart 75i filter has an activated carbon filter that adsorbs cooking odor (perfect for removing cooking oil smell), smoke from cigarettes, candles, or smoke fumes from gasoline and diesel cars coming in from the street.

B7-MP-Pet is a ‘Pet filter’ because it enables Alen BreatheSmarth 75i to capture pet dander and pet odor more efficiently. If you have a dog or a cat, this is a smart choice:

To turn the Alen BreatheSmart 75 air purifier into a true powerhouse, you can choose the B7-MP-Odor filter with a heavy activated carbon filter that captures a large amount of undesirable odors, even baby diaper smells.

Here the main advantage of these filters:

They have extremely high 99.99% efficiency. They are all-in-one filters; you only have to replace that one filter. Not every 4 months, not every 6 months, but actually every 12-15 months. Overall, Alen 75i main filters cost about $130.

replacing alen breathesmarth 75i filter
Here’s how replacing the Alen BreatheSmart 75i filter looks like. Easy and only once per year.

That’s 1 filter replacement per year if you use the Alen BreatheSmart 75i. In comparison, the majority of other air purifiers will need 3 HEPA filter replacements per year and 2-3 activated carbon filter replacements per year. The full costs of that can easily surpass $300; in comparison, $130 for Alen BreatheSmart 75i filter can save you about $200/year just in filter costs.

Alen BreatheSmart 75i CADR Rating And Maximum Airflow

Every air purifier, including the Alen BreatheSmart 75i, works by combining a filtration system (CADR rating) and a fan (airflow).

The CADR rating is the single most important metric for any air purifier. It stands for Clean Air Delivery Rate and it tells us how well does the Alen BreatheSmart 75i remove air pollutants like dust, pollen, and smoke.

The CADR rating scale goes from 0 to 450, with most standard air purifiers having around 200 CADR rating.

In comparison, Alen BreatheSmart’s 75i rating is 400. That’s way above average by a large margin. It, in essence, tells us that Alen BreatheSmart 75i’s filtration system combined with the powerful fan removes air pollutants much better than almost any other air purifier.

backside of alen breathesmarth 75i
75i model sucks in all the air in the back and creates an airflow from the back to the front and up.

Where the beauty of a well-balanced 75i comes in is the airflow. Big air purifiers are known to have 300+ CADR rating but they need to create 600+ CFM airflow to achieve that; which also means they are very loud.

Alen BreatheSmart 75i engineers have managed to create an air purifier that achieved a 400 CADR rating at, get this, only 350 CFM. This is precisely the reason that makes Alen BreatheSmarth the #1 rated air purifier currently on the market; no other unit comes close to this CADR-to-CFM ratio.

Alen BreatheSmart 75i Square Footage (Recommended Room Size)

Due to an extremely high CADR rating, the Alen BreatheSmart 75i is considered a large room air purifier.

It can achieve 2 air changes per hour (2 ACH) in 1,300 sq ft rooms. That means that it will filter all the air in this area every 30 minutes.

maximum coverage area for alen breathesmart 75i air purifier

For allergy-prone people, 5 ACH is recommended. Alen BreatheSmart 75i can filter all the air in 520 sq ft rooms every 12 minutes; yielding 5 air changes per hour.

Do you really need to put Alen BreatheSmarth 75i only in large 1,300 sq ft bedrooms?

Not at all.

75i model has 4 fan speed settings and a turbo setting. The 1,300 square footage is valid for the turbo setting.

Here are the Alen BreatheSmart 75i speed settings, airflow, calculated CADR rating, and room size calculation for 2 and 5 ACH:

75i Fan Speed Airflow Calculated CADR Coverage (2 ACH) Coverage (5 ACH)
Speed 1: 95 CFM 109 355 sq ft 142 sq ft
Speed 2: 170 CFM 194 630 sq ft 252 sq ft
Speed 3: 240 CFM 274 890 sq ft 356 sq ft
Speed 4: 280 CFM 320 1,040 sq ft 416 sq ft
Turbo Speed: 350 CFM 400 1,300 sq ft 520 sq ft

This might be a confusing table but here’s the convenient part:

You don’t need to know any of this because Alen BreatheSmart 75i auto-adjusts the speed based on measured air quality (Smart Sensor tech).

You can monitor how the indoor air quality is continuously being improved on the Alen BreatheSmart 75i’s control panel:

monitoring indoor air quality on alen 75i control panel
Alen BreatheSmarth 75i will automatically adjust the fan speed to maximize indoor air quality. You can monitor air quality in real-time just by looking at 75i’s control panel.

Now, big and high-performance air purifiers tend to use a bit more electricity. Is this the case with Alen BreatheSmarth 75i as well?

Alen BreatheSmart 75i Power Consumption (Wattage)

Standard-sized air purifiers don’t use a lot of electricity. Bigger high-capacity units like Alen BreatheSmart 75i (especially with 400 CADR rating) should, in theory, use a lot of electricity (especially if you run them as you should – all the time 24 hours/day).

Even in this regard, the Alen BreatheSmart 75i positively surprises us. Comparable large room air purifiers will need more than 100W of power to run on turbo speed; Alen BreatheSmart 75i needs only 45W.

It’s just incredible how energy-efficient the 75i model is. 45W is its top power setting. When you achieve a very clean indoor air quality, it will run on Speed 1 to sustain that high air quality. It will need only 1.8 watts of electricity for that.

Here’s the incredible part:

If you run it on 1.8W Speed 1 setting 24/7 for a whole year, the Alen BreatheSmart 75i total wattage usage per year will be less than 16 kWh. 16 kWh costs about $2; we’ve double-checked these numbers, it’s not a mistake.

In short, the 75i air purifier might cost a pretty penny to buy but the maintenance costs couldn’t be lower. In the long-term, that’s a major bonus.

Alen BreatheSmart 75i Noise Levels

Alen BreatheSmart series air purifiers are specially designed to improve not only indoor air quality but sleeping quality as well. To achieve that, Alen BreatheSmart 75i must have a silent operation.

Any bedroom air purifier should be silent, even on the highest fan speed setting. Nowhere is that more apparent than in Alen BreatheSmart 75i noise levels.

where to place alen breathesmart 75i air purifier
Alen BreatheSmart 75i is so quiet you can place it pretty much anywhere; in the dining room, bedroom, living room. You can bet you won’t hear it purring silently.

Speed 1 will generate only 25 dB of noise. This is by several classes lower minimal noise level, compared to other air purifiers. On the highest setting – Alen BreatheSmart 75i’s Turbo Speed – the air purifier will generate not less than 60 dB. It will, in fact, generate less than 50 dB; 49 decibels to be exact.

75i model holds a rank of its own among the biggest air purifiers as far as the noise levels are concerned. This is the only 400 CADR rated air purifier with such a silent operation.

Alen even contacted SleepScore Labs to test how the Alen BreatheSmart 75i can improve sleeping quality. Here’s the outtake of that study:

“The SleepScore Labs’ validation study shows using an Alen air purifier in the bedroom improved overall sleep in people with sub-clinical sleep complaints that were otherwise healthy.”

Quiet operation in no small part contributes to these results. Alen BreatheSmart 75i is exceptionally efficient at improving indoor air quality, and, what’s perhaps more important, is does it very silently.

Alen BreatheSmart 75i Special Features

There are a number of features Alen BreatheSmart 75i has (the ones that we have already covered) that are considered quite special. These include:

  • Incredible air cleaning efficiency due to the use of H13 medical-grade HEPA filters.
  • Extreme energy-efficiency (max. wattage = 45 W).
  • Quiet operation (up to only 49 dB).

Among other features there are two that are especially useful:

  • Smart Sensor technology. Measures air quality in real-time and adjusts the Alen BreatheSmart 75i’s fan speed to maximize the removal of any leftover air pollutants.
  • Lifetime warranty. Alen was the first company confident enough in their air purifiers to put into effect a ‘Guaranteed Forever’ warranty. Alen BreatheSmart 75i is extremely reliable and doesn’t breakdown frequently. If it does, the Alen team will help you with support, replacement parts, or even a new device.

alen breathesmart 75i warranty

On top of that, you get all the basic features such as Set Timer for 2, 4, or 12 hours and filter indication that tells you when to replace H13 HEPA filters.

Alen BreatheSmart 75i Price

Despite the unmatched performance, some people might balk at the price of the Alen BreatheSmart 75i. As always, it’s important to understand that the true cost of any air purifier are the replacement filters.

Alen BreatheSmart 75i costs about $700 to $800. That alone seems like a high price point, especially compared to $100 air purifiers. Why would you even consider buying the Alen BreatheSmart 75i air purifier if you can get some other air purifier for $100?

Here’s exactly why Alen BreatheSmart 75i price is justified:

  • You will need 4-5 small $100 air purifiers to match the air cleaning capacity of Alen BreatheSmart 75i.
  • Replacement filters for each $100 unit (3x HEPA filter + 2x activated carbon filter yearly) will cost about $100/year for each unit. That’s $500 for replacement filters vs. $130 for the Alen BreatheSmart 75i replacement filter.
  • You are actually getting an air purifier so superior in specifications, materials, and aesthetics that no other below $500 can even come close.

As always, we try to seek out some deals to lower the price of every air purifier we review:

Alen BreatheSmart 75i Sale

The standard price of the Alen BreatheSmart BreatheSmarth 75i is $749. The price is reasonable for a high-quality bug air purifier with such renown as Alen.

Do keep in mind that you can choose between 4 different main filters. You also have a lot of Alen BreatheSmart 75i color options; from basic white to Brushed Stainless, Espresso, Weathered Gray, Oak, and Graphite.

We keep up with all Alen BreatheSmart 75i sales. You can check the current sale here:

Check Alen BreatheSmart 75i Sale

Final Verdict On Alen BreatheSmart 75i

Alen BreatheSmart is a remarkable series of powerful and quiet air purifiers. The big 75i model is the newest flagship with the most outstanding specs not only among Alen air purifiers but all purifiers in general.

The combination of extremely high CADR rating, H13 HEPA filters, very low noise levels, superb features like Sensor Smart tech, and an affordable price with the lowest possible maintenance cost has earned the Alen BreatheSmart the highest rating among all air purifiers.

In fact, 75i is the only model that has ever earned a perfect 5-star rating by LearnMetrics. That’s why it has also earned the #1 rank on the list of the best air purifier in 2024.

Overall Alen BreatheSmart 75i rating: 5 out of 5 stars

2 thoughts on “Alen BreatheSmart 75i Review: Arguably #1 Air Purifier In 2024”

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