
Alen Air Purifier Review: Compare The Best Deals 2023

2023 Best Alen Air Purifier Review
BUDGET-FRIENDLY | BEST VALUE 🥇 | BEST PERFORM-ANCEPERFORMANCE |
---|---|---|
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Alen BreatheSmart Classic Air Purifier | Alen BreatheSmart 75i Air Purifier | Alen BreatheSmart 45i Air Purifier |
Recommended Room Size | ||
1,100 sq. ft. (102 m2) | 1,300 sq. ft. (121 m2) | 800 sq. ft. (74 m2) |
CADR | ||
Dust 300 cfm (510 m3/h) Pollen 300 cfm (510 m3/h) Smoke 300 cfm (510 m3/h) | Dust 347 cfm (590 m3/h) Pollen 347 cfm (590 m3/h) Smoke 347 cfm (590 m3/h) | Dust 245 cfm (416 m3/h) Pollen 245 cfm (416 m3/h) Smoke 245 cfm (416 m3/h) |
Filtration | ||
3-stage | 3-stage | 3-stage |
Ratings | ||
4.5 ★ out of 5 | 4.6 ★ out of 5 | 4.2 ★ out of 5 |
Amazon Price | ||
$$$$$$$ | $$$$$$$ | $$$$$ |
CHECK LATEST PRICE | CHECK LATEST PRICE | CHECK LATEST PRICE |
Pros
- Swappable front cover design.
- Wide purifying coverage and superior airflow delivery rate.
- Up to 3 optional filter upgrades, depending on your needs.
- Ionizer could be turn on or off.
- Longer lasting filters (up to 18 months) depending on usage volume/ air quality.
- Accurate Smart Filter Light indicator based on usage/ fan speed/ environment.
- An abundance of features - SmartSensor, auto mode, filter life, pre-set timer.
- Child-friendly with child lock and safe vent guard.
- Alen unique Lifetime Limited Warranty (active filter subscription).
Cons
- Lacks odor filtration on bundled HEPA-Pure filter (Optional filter upgrade required).
- No dedicated odor carbon filter that could come in handy during filter replacement.
- A little noisy at the highest speed. Nevertheless, the Auto mode will come to the rescue.
Design - The one that started it all. Alen BreatheSmart air purifier classic is the OG model with everything you need. At a console size of 17.8 inches in width, 26.8 inches in height, and 10 inches in depth, you might have difficulty placing it in a tight area. Thankfully the 21 lb weight is manageable; you can use Alen BreatheSmart around the house via the back handle. The modern exterior supports many customizable panels that you can purchase to enhance the look and feel. Air inlets are nicely tucked at the sides and bottom with an air outlet at the top for extended distribution.
Functionality - Usability-wise, the Alen Classic BreatheSmart air purifier has a conventional button-operated control that is very straightforward to use. You have a standard 4 fan speeds ( 1, 2, 3, turbo) plus SmartSensor auto mode that only uses top speed when indoor air quality worsens. You can also set the 4, 8, 12 preset countdown timers to shut down the air purifier and lock the controls via child lock. Surrounding the main power button is the AQI, which will display blue when indoor air is clean, yellow when moderate, and red when indoor air is dirty. Other features include the option to enable/ disable the ionizer and filter indicator light that resets the filter life from red to green after successfully replacing the filter.

Overall, the build quality is solid, with no byproducts and air by-pass leakage. Alen BreatheSmart Classic is UL listed and Energy Star certified within the 40% energy efficient range. It is also shielded by Alen's lifetime limited warranty with product registration and active filter subscription. Expect nothing less from the air purifier despite being the most dated BreatheSmart model.
Coverage - Air cleaning performance without compromise. Alen BreatheSmart Classic air purifier can cater to an ample 1,100 square footage of room size at 2 air changes per hour or every 30 minutes. For those that need higher clean air frequency, you can increase to 4 air changes per hour or every 15 minutes at a reduced 690 square footage. The airflow delivery rate ranges from 150 cfm to 286 cfm (turbo speed). On the other hand, CADR is estimated to be around 300 cfm for dust, pollen, and smoke. The strong output works flawlessly in the living room, lounge, bedroom, basement, garage, kitchen, or playroom. You can see almost instant changes in your home air quality within hours of running the machine.
3-stage HEPA filtration with 1,100 sq. ft. and 300 CADR.
Filtration - By default, the Alen BreatheSmart Classic air purifier comes with a HEPA-Pure bundled filter set that covers most household pollutants. The permanent pre-filter traps large particles like hair, lint, and dust so they will not clog and damage the HEPA filter. Unlike other disposable filters, it is also the only filter you can wash and reuse. The medical-grade True HEPA filter capture 99.99% of airborne particles as small as 0.1 microns. For an asthmatic person, you can opt for the add-on HEPA-Silver filter upgrade that specializes in removing biological pollutants like mold, mildew, and germs. To deal with toxic fumes, choose the HEPA-FreshPlus filter that neutralizes chemicals like VOCs, cigarette smoke, carbon monoxide, and radon. HEPA-OdorCell filter absorbs musty smells, stinky pets, diapers, and other nauseating odors in a household. Lastly, the optional ionizer release negative ions that electrostatically attach to positive ion particles in the air. The combined particles will fall due to the increased weight allowing the Alen BreatheSmart air purifier to capture them.
Noise and power - With its famous WhisperMax technology, Alen BreatheSmart Classic output an average of 42 to 56 decibels. Not the quietest but certainly not the loudest either. In auto mode, you will barely hear any fan noise unless an increase in airborne pollutants is detected. Despite the high airflow output, BreatheSmart is ideal for all-day use, where you can run it 24/ 7 during work or sleep. Power consumption is on the higher side for an Energy Star Certified model. Running between a max of 64-105 watts, you might feel the slightest pinch on the monthly utility bill with continuous daily operation.
Pricing - For around 650 dollars before any discount or add-ons, the Alen BreatheSmart air purifier has a hefty price tag that might not bold well with many. However, you are getting a highly customizable, best air cleaning performance and specification bar for the WiFi-enabled feature. Another drawback is the default HEPA filter does not come with a carbon filter unless you top-up for the optional upgrade. Highly recommended to do so, as the recurring filter cost is quite affordable. The last minor complaint is the audible background white noise when Alen BreatheSmart runs on turbo speed. Definitely not a deal-breaker.
There is no question about the capabilities of the Alen BreatheSmart air purifier but ask yourself, what is the purpose of purchasing an air cleaner? If it is for allergies-related purposes, it will do an excellent job dealing with that. Ignoring the cons, Alen BreatheSmart is our top pick when we want the best non-WiFi, HEPA air purifier.
±649.00 $$$$$$$/ 7

(annual filter cost ±46-138)
Pros
- The widest and strongest airflow performance in the Alen BreatheSmart series. Cleans up to 1,300 square feet of room space.
- All upgradable H13 HEPA filters come with antimicrobial treatment to prevent microorganisms' growth.
- Ionizer that can be disabled for complete Ozone-free purification.
- Longer-lasting filter that can last up to 18 months on normal use.
- Child lock, 5 speeds, Auto/ lights-off mode powered by the newer intelligent sensor.
- Pink noise operation with minimal disruption even on the highest speed.
- Guaranteed for life when used correctly (registered, active filter subscription, no counterfeit filters).
Cons
- Expensive (above $700 price point) for this top-of-the-line model.
- No smoke and odor filtration on the HEPA Pure filter. You will need to upgrade to Fresh/ Pet/ Heavy Odor to remove gaseous pollutants.
- Uses an all-in-one filter set that cannot be replaced individually. Fortunately, the filter cost is still within a reasonable realm.
- Bulky and heavy, which limits the places you can place the air purifier.
Design - The latest and greatest Alen BreatheSmart air purifier to date. At a reasonable size of 18.5 x 27 x 11.5 inches, Alen BreatheSmart 75i houses a familiar console design that we have loved for years. The modern aesthetics are complemented by custom panels that you can swap out with many available designs. The 27 pounds weight is on the heavier side to carry but not totally impossible for room-to-room purifying. Air inlets are located at the sides for more even coverage, plus a back handle that helps portability. Fitting is tight, with no signs of harmful byproducts released.
Functionality - As always, Alen BreatheSmart 75i is CARB approved ozone-safe that produces less than 0.001 PPM of ozone with ionizer enabled. Reliability is also one of the key selling points as the lifetime warranty guarantees trouble-free ownership with an active filter subscription.

Using Alen BreatheSmart 75i air purifier is a joy as everything is laid out symmetrically in front of you. You can select up to 5 speeds, including the high-performance turbo and Auto mode. In auto mode, the air purifier will move the fan speed up or down depending on the room's air quality. There is also a lights-off sleep mode that activates automatically when the room is pitch back after a couple of minutes. The dedicated child lock function prevents children from messing with the setting, and the optional ionizer can be activated/ deactivated at a click of a button. Another surprising feature that many people don't know is that Alen BreatheSmart 75i is actually WiFi enabled by default. You can access most of its functions via your smartphone, but the app is still under development last we checked.
Continue the features list; a 2, 4, 12 hours countdown timer can be set to turn off the air purifier. Circling the power button is the AQI light that will be in blue when air quality is excellent, green when air quality is good, orange when air quality is fair, red when air quality is poor, and purple when air quality is bad (dirty). Last but not least, the real-time filter indicator light will let you know the exact time to replace the filter based on usage.
Coverage - Alen BreatheSmart 75i is the pinnacle of a large room air purifier that delivers strong and consistent airflow between 95 to 350 cfm. Under normal circumstances, it can reach up to 1,300 square footage of air cleaning space with 2 air changes per hour (30 minutes). For an asthmatic sufferer or a sick person, you can increase to 4 air changes per hour (15 minutes) and still receive a healthy 650 square footage of purifying coverage. CADR tally with the airflow delivery rate averaging around 347 cfm for dust, pollen, and smoke. Place Alen BreatheSmart 75i in large room sizes or equivalents like living room, mansion bedroom, finished basement, garage/ workshop, home offices, nursery home, or playroom.
3-stage HEPA filtration with 1,300 sq. ft. and 347 CADR.
Filtration - The best air purifier deserves the best medical-grade filtration. Nearby air pollutants will be drawn in via the motor fan and blocked by the washable pre-filter from passing through. With most PM10 particles trapped, the H13 True HEPA filter capture 99.99% of airborne particles down to 0.1 microns, including mold, mildew, pollen, lead dust, germs, bacteria, and viruses (independently lab tested). While it is effective and sufficient for most residential homes, you can up the filtration grade from a mere 20 dollars. Choose from HEPA fresh filter for chemical and mild odor, a HEPA Pet filter that specializes in capturing pet-related allergens, or HEPA heavy odor filter that is perfect for heavy odors, including baby diapers. The ionizer discharges millions of natural negative ions that merge with positive ion airborne pollutants, causing them to fall and be captured. Negative ions are safe and beneficial to our health despite producing insignificant ozone. You can disable it at any time if you feel uncomfortable using it.
Noise and power - Another good thing about the Alen BreatheSmart 75i air purifier is the added power did not affect the noise output. You're still getting a whisper-quiet 25 decibels noise level at the lowest speed to a max of 49 decibels, similar to rainfall. The auto-sleep mode allows you to sleep soundly at night without breathing in dangerous allergens. Power usage is also under Energy Star's 40% efficient tier, so it will not hit you with a hefty bill at the end of the month. You can leave the Alen BreatheSmart 75i air purifier running all day comfortably without any noise distraction.
Pricing - If you want the best, you will have to pay for it. The starting price of Alen BreatheSmart 75i is around 750 dollars before accounting for the addon panels and filter upgrade. That's about 100 dollars more premium over Alen BreatheSmart Classic for a slight performance boost and WiFi-enabled feature. Fortunately, the all-in-one filter set is convenient to replace and at a reasonable under 100 price. However, there is no option to replace them individually. We do think the air filtration performance itself will cover the cost; there are other cheaper Alen BreatheSmart alternatives below that you could consider as well.
Alen BreathSmart 75i is a solid upgrade from the series, known for its trusted filtration system and customizable setup. If you can look past the drawbacks, you will be rewarded with all the smart features, auto cleaning mode, and lifetime warranty. For those with a large family, a company with more than 5 workforces, or a classroom packed with students, Alen BreathSmart 75i is a sensible choice.
±749.00 $$$$$$$/ 7

(annual filter cost ±66-99)
Pros
- Minimalist and lightweight design with no shortage of front panel designs.
- Comprehensive purifying coverage with superior airflow distribution.
- Customizable filter with up to 3 optional H13 HEPA filter upgrades.
- Uses the same long-lasting filter set as BreatheSmart Flex.
- Newer intelligent sensor to support the air purifier auto/ lights-off mode. Runs quiet enough that it will not disrupt your sleep.
- Like most of Alen's newer air purifiers, you can easily lock 45i controls.
- A guaranteed lifetime warranty protects from any manufacturer's defect (with product registration & active filter subscription).
Cons
- Lacks chemical and odor filtration on the standard HEPA-Pure filter. Upgradable with additional cost.
- While the all-in-one filter setup is easy to replace, you cannot change them individually.
Design - Want 75i but can't bear the high price tag? Alen BreatheSmart 45i air purifier has you covered. It is a smaller but identical model with many beautiful custom panels you can choose from. At a 15 inches width, 25 inches height, and 8.5 inches depth, the air purifier fits well in most homes without cluttering up your interior space. You can move it around for room-to-room purifying via its reasonably light 15 pounds weight. Just grab onto the back handle to bring it wherever you go. Design-wise, it uses the familiar console setup with air inlets at both sides and a top air outlet. Build quality is on par with the rest of the Alen lineup, so it will withstand some rough usage. Alen BreatheSmart 45i is officially UL listed and ozone-safe, emitting less than 0.001 PPM of ozone. The lifetime warranty is the best advocator of reliability that guarantees a worry-free purchase.

Functionality - Alen BreatheSmart 45i comes with all the standard features that can be accessed via the top control panel. Choose between the 4 fan speeds (Low, Medium, High, Turbo), activate the ionizer, or use the Smart sensor-driven auto mode. In auto mode, Alen BreatheSmart 45i autonomously sets the fan speeds high when air quality drops and low when the air quality improves. You can see the immediate changes to the air quality via the AQI color rings at the center. There is also a sleep mode that activates automatically when there is no light detected. A 2, 4, 12 hours timer shut down the air purifier to help converse energy. The filter reset button with a real-time indicator alerts you when the filter requires replacing. Like 75i, Alen BreatheSmart 45i comes with WiFi capacity, but many people are unaware of it as it is not heavily promoted. To gain remote access to the air purifier controls, you must pair it with your smartphone and use third-party apps like TUYA's "Smart Life."
3-stage HEPA filtration with 800 sq. ft. and 245 CADR.
Coverage - Place below the 75i, the lower variant Alen BreatheSmart 45i air purifier still delivers a wide 800 square footage of air cleaning at 2 air changes per hour (every 30 minutes). Increase to 4 air changes per hour (every 15 minutes) for a reduced 400 square footage of purifying coverage. CADR is averaging 245 cfm for dust, pollen, and smoke tested according to AHAM guidelines. With 70-215 cfm of airflow delivery rate, you can enjoy clean, fresh air within 1-2 hours. Suitable for loft, studio apartment, or standard residential home within Alen BreatheSmart 45i cleaning radius.
Noise and power - The reduced airflow performance did not give Alen BreatheSmart 45i an edge over its 75i counterpart. Depending on the air purifier's fan speed, it outputs a silent 23 to 49 decibels noise level. It will not disturb your sleep, even if you're not a big fan of white background noise. Likewise, the Energy Star power consumptions are identical to the higher variant at around 45-50 watts hourly. In most states, it will only cost you between 2-5 dollars monthly to keep Alen BreatheSmart 45i running all day.
Filtration - Independently lab tested on its efficiency, Alen BreatheSmart 45i can protect you and your family from harmful airborne allergens. The permanent pre-filter traps large PM10 particles that flow in and prevent them from clogging the HEPA filter. The standard H13 True HEPA filter captures 99.99% of airborne allergens down to 0.1 microns e.g. dust mites, mold, pollen, pet dander, bacteria, and viruses. Since the default HEPA-pure filter does not come with any smoke filtration, you can upgrade it with HEPA fresh filter with antimicrobial treatment for an extra 15 dollars. HEPA OdorCell filter is great that absorbs strong odors coming from common sources such as pets, foods, and diapers. Add another 30 dollars to opt for the premium Heavy smoke HEPA filter with 2+ lbs of activated carbon that neutralize chemical fumes, VOCs from aerosol sprays and paints. There is also a filter-free ionizer that pulls down pollutants in the air for the HEPA filter to capture. Ion technology is a proven and safe technology that generates natural negative ions rather than harmful ozone that many are misled so.
Pricing - Around 300 less than its counterpart, Alen BreatheSmart 45i is listed at around 468 dollars before discount. A great deal considering the specs you will get is a mirror to 75i. Nonetheless, it is still far from cheap compared to what Levoit and Winix offer. The filter replacement can be costly depending on the filter type and how unhealthy the indoor air quality is. Other niggling complaints include the limited support for WiFi and expensive custom panels. None will affect its airflow performance.
To conclude, Alen BreatheSmart 45i True HEPA air purifier lived up to the expectations of Alen's fantastic product lineup. It is energy-efficient, easy to operate, and runs silently at most speeds. Alen BreatheSmart 45i also works great in removing smoke and odors, providing you opt for the filter upgrade. You will be rewarded with clean air free from smoke and odors within 30 minutes of runtime. When indoor air quality improves, your health and breathing patterns will also improve. Symptoms like cough, sinus, itchiness, and inflammation will be alleviated. Get this if you want a solid air purifier that can remove a wide range of airborne allergens in medium to large-sized rooms.
±468.00 $$$$$/ 7

(annual filter cost ±39-118)
Pros
- Multiple color option/ wood trim design front panel covers.
- Excellent purifying coverage and airflow delivery rate for its segment.
- 3 specialist filter upgrades (HEPA-FreshPlus, HEPA-Silver, HEPA-OdorCell).
- Longer lasting filters (up to 18 months) on regular use.
- Smart Filter replacement indicator calculates filter lifespan based on usage/ fanspeed/ environment.
- 4 fan speed with Auto mode, SmartSensor, and pre-set timer.
- Child-friendly machine with safe vent guard.
- Lifetime Limited Warranty with active filter subscription.
Cons
- HEPA-Pure filter lacks odor filtration. Optional filter with deodorization upgrade requires top up.
- No dedicated odor carbon filter to support the HEPA filter. Uses only a single all-in-one filter.
Design - A mid-child between Classic and Flex, the Alen FIT50 air purifier is a modern yet familiar air purifier from the Alen BreatheSmart lineup. At a smaller body size of 16.8 x 22.3 x 10 inches and a total weight of just 16 pounds, moving Alen BreatheSmart FIT50 is an effortless chore. We are a big fan of the Rosewood custom panel that adds flair to a home. If you aren't, there are more than a dozen of add-on custom panels you can purchase. Air inlets are nicely tucked behind with a conventional top air outlet placement. Build quality is solid and is protected by Alen's lifetime limited warranty. An incredible perk that we mentioned time and time again.

Functionality - Alen BreatheSmart FIT50 air purifier comes with a classic control panel that is well labeled with dedicated indicator lights. You can cycle between the 4 fan speeds and activate/ deactivate the ionizer based on your preference. The built-in Smart Sensor allows Auto mode that uses higher fan speed when there is a large concentration of air pollutants nearby. Advanced Smart Filter accurately reads and alerts you to replace the filter set based on usage/ condition. The AQI will change its color based on the surrounding air quality. It will illuminate blue when the air quality is good, yellow at a moderate level, and red when high levels of air pollutants are detected. The child lock button prevents children or pets from messing with the controls. You also have the option to disable all display lights to reduce glare during sleep.
Coverage - Alen BreatheSmart FIT50 is no slouch when it comes to air cleaning performance. With an airflow delivery rate of 110 to 231 cfm, it will have no problem removing all types of indoor air pollutants. At full speed, it can cover a wide 900 square footage at 2 air changes per hour (every 30 minutes) or 450 square footage at 4 air changes per hour (every 15 minutes). Dust, pollen, and smoke CADR are rated at an average of 220 cfm as tested by ENERGY STAR. Ideal for large room sizes like living room, bedroom, kitchen, basement, garage, nursery home, and open space office.Noise and power - On to everyday usability. Alen BreatheSmart FIT50 Noise is well-contained thanks to its WhisperMax technology. It outputs a low noise of 32 to 49 decibels that will not cause a disturbance when you're trying to work or get a shut-eye. Even running at turbo speed, the low pitch, pink noise generated can act as soothing background noise for those with trouble sleeping. Power consumption averages 60 watts hourly, depending on the operating speed. Similar to other Energy Start certified BreatheSmart models, it will be gentle on your monthly utility bill.
3-stage HEPA filtration with 900 sq. ft. and 220 CADR.
Filtration - The filtration that never fails. Alen BreatheSmart FIT50 works by pulling air in via its motor fan. The washable pre-filter velcro to the HEPA filter will block large airborne particles like dust, lint, and hair. Since it is reusable, you can easily take out the pre-filter for cleaning to prolong the HEPA filter lifespan. In return, the protected HEPA filter can focus on capturing fine particles in the air, like mold, pollen, pet dander, and germs. To deal with smoke particles, you can choose to upgrade the default HEPA-Pure filter with either the HEPA-FreshPlus filter that targets chemicals, smoke, VOCs, the HEPA-Silver filter that specializes in mold, germs, and other allergens linked with asthma or HEPA-OdorCell that neutralize strong odors like stinky old diapers, food, pets. The final ionizer will continue releasing negative ions to attach and pull down positive airborne pollutants for the filter to capture before releasing clean air back into the room.
Pricing - With the newer 45i and 75i series dominating BreatheSmart sales, the Alen FIT50 air purifier is a value buy for those needing filtration performance but don't mind a dated model. Keep in mind that the estimated 549 dollars are not everyone's cup of tea, not even accounting for the filter upgrade and add-on purchase. Many people will go with the Classic BreatheSmart, 45i, or the cheapest Flex that shares many parallel elements. Once you bypass the expensive purchasing cost, the filter replacement cost is actually more attainable if you could stretch it out to 18 months. On normal use, it will cost you between a low of 46 to 138 dollars annually. So if you are going with FIT50, do check out Alen BreatheSmart 45i for a better comparison.
You can never go wrong with a BreatheSmart. Alen Fit50 is a mid-range model from its lineup with little compromise. It is undoubtedly the ideal choice if you want something more attainable than Classic and 75i yet shares the purifying effectiveness, reliability, and durability. Fit50 VS 45i: which one would you pick?
±588.00 $$$$$$$/ 7

(annual filter cost ±53-158)
Pros
- Changeable front panel with tons of modern wood trim design.
- Consistent and robust airflow delivery rate.
- Choose up to 3 optional filter upgrades.
- Longer lasting filters compare with similar segment air purifiers.
- Built-in timer (2, 4, 12 hours).
- Child friendly machine with child lock and safe vent guard.
- Lifetime Limited Warranty (with active filter subscription).
Cons
- Lacks odor filtration on the default HEPA-Pure filter.
- Lacks advanced filter replacement indicator (only basic version), SmartSensor (thus Auto mode), and Ionizer. All these features are available in BreathSmart FIT50.
Design - The cheapest, smallest, and most flexible BreatheSmart model to date. Alen FLEX is an attainable air purifier for those who don't need much air cleaning. Featuring a dimension of just 15 inches in width, 25 inches in height, and a slim 8.5 inches in depth. You can place Alen BreatheSmart FLEX even in tight places that other BreathSmart models simply can't. The light 15 pounds weight, including the filter, allows you to move the air purifier around the house with relative ease. Shift from your home desk in the morning, kitchen while cooking, to bed at night simply by grabbing the back handle. Design-wise, you can choose from many colors to a wood trim design from the BreatheSmart trademark custom panels. The side air and bottom air inlets synchronize well with the top air outlet. No cutting cost measures on the build quality as everything remains top-notch, complimented by Alen's lifetime warranty.

Functionality - Instead of physical buttons, the Alen BreatheSmart FLEX air purifier has a capacitive touch panel that chimes. The well-lit buttons allow you to cycle between the 4 fan speeds, including Turbo mode, which swiftly cleans the air when the indoor air has gone bad. A 2, 4, 12 hours timer can also be set to turn off the air purifier. The filter life button reset the red indicator light and countdown time after successfully changing to a new filter. Lastly, the lock function disables all controls, so children would not be able to mess with the settings. Simply press and hold the lock buttons for 3 seconds to unlock it. The 2 obvious functions missing here are the auto and ion mode to accommodate the lower price bracket.
Coverage - Here's where Alen BreatheSmart FLEX HEPA air purifier differentiates itself from others. You're getting a reduced 700 square footage air coverage at 2 air changes per hour or 350 square footage at 4 air changes per hour. Not bad for smaller room spaces like bedroom use, kitchen, small basement, garage, and studio home. The reduced airflow delivery rate of 53 to 187 cfm also resulted in a lower CADR at an estimated 245 cfm range. It will take slightly longer to clean the air in your home.
2-stage HEPA filtration with 700 sq. ft. and 245 CADR.
Noise and power - Another Alen's hallmark, the WhisperMax technology helps keep noise levels from a whisper of 39 decibels to white, pink noise of 55 decibels. Again, the lack of auto mode means you will have to manually adjust to the lowest speed before you head to bed to keep the noise down. Energy Star certified power usage is at an efficient 36 watts hourly. One of the lowest from the BreatheSmart series, given its weaker power output. It will not increase your electricity bill significantly after long-haul.
Filtration - Despite the small body, Alen FLEX uses the same filtration as other BreatheSmart models. The velcro attached pre-filter protects and blocks large particles like dust, hair, and lint from clogging the HEPA filter. Depending on the filter sets you opt for, the default HEPA-pure filter is effective at capturing microscopic particles like mold, pollen, pet dander, and lead dust. To counter smoke and odor, upgrade to the HEPA OdorCell filter that specializes in absorbing stinky smells from food, diapers, or pets. To deal with stronger chemicals, choose the HEPA FreshPlus filter that removes asthma triggers like cigarette chemicals, VOCs, and smoke. The HEPA Silver filter deals with mold, germ, bacteria, and other biological pollutants. Out of the 4 filter sets, we recommend going with OdorCell or FreshPlus filter that comes with the much-appreciated carbon filter.
Pricing - For around 349 dollars, the Alen BreatheSmart FLEX air purifier is the cheapest in the lineup but comes at a cost. You're getting a much weaker air purifying performance and CADR right off the bat. The air quality indicator and auto mode are also missing due to the lack of a built-in sensor. If you want the latter 2 features, choose FIT50 or 45i, which offers both. On the flip side, annual filter replacement is the most economical, between 39 to 118. The longer you can stretch the usage of the filter, the more cost-efficient it will be.
Bring to a conclusion, the Alen BreatheSmart FLEX HEPA air purifier is a remarkable, budget-friendly option for containing household contaminants and allergies, as long as you choose the right type of filter. Comparing the advantages/ disadvantages, there are many more strong suits over the negative ones. Our heart still goes for Classic, but choose Alen BreatheSmart FLEX if the money is tight.
±349.00 $$$$/ 7

(annual filter cost ±39-118)
Pros
- Comprehensive purifying coverage for a tower air purifier.
- Easy to bring around thanks to the compact size and back handle.
- Upgradable HEPA filters depending on your individual needs.
- Covered by Alen's lifetime warranty.
- Up to a maximum of 12-hour timer.
- Subtle noise level even at the highest setting.
Cons
- No stand-alone deodorization filter.
- An optional filter purchase (HEPA-OdorCell) is required to deal with odors.
- Lacks air quality sensors and Auto mode, especially at this price point.
Design - The oldest, smallest, and most affordable tower air purifier in Alen's current lineup. Non-BreatheSmart Alen T500 air purifier is only 10 inches in width, 22 inches in height, and 6 inches in depth. Perfect for a TV cabinet, desktop, and bedside placement as it occupies little space. The under 9 pounds weight is perfect for bringing it around everywhere you go, even on a staycation. While the conventional design is more practical than aesthetic with surrounding air inlets, it is highly functional, which is important for an air purifier at this price point. The fitting is good, with no signs of off-gassing or misalignment. You're getting the complete Alen lifetime Limited Warranty despite the budget price.
Functionality - Alen T500 is straightforward to use despite the old-school non-digital controls. You can adjust the 3 fan speeds, set the 12-hour timer, and reset the filter indicator light after changing the filter. A dedicated ionizer button allows you to turn on or off the ionizer at any point of the purification. No air quality indicator, auto mode, or sleep mode is available, given the non-existence sensor. Everything has to be done manually.
Coverage - Designed for desktop use, the Alen T500 air purifier can cover up to 500 square footage of room space at 2 air changes per hour. More than enough for close-range use when the air purifier is close to you during work or sleep. The airflow delivery rate is from 48 cfm and peaks at 130 cfm. CADR is averaging 159 cfm for dust, pollen, and smoke. Not magnificent, but it will be more than decent for most folks at home.
Noise and power - The noise level is not in Alen T500 favors at its outputs of 42 to 56 decibels despite the reduced airflow delivery rate. You can still use it quietly by keeping the fan speed low. Power consumption is efficient between 30 to 53 watts, but we have seen more energy-saving units for its segment. Again, no auto or sleep mode to help manage the noise and energy efficiency.
3-stage HEPA filtration with 500 sq. ft. and 159 CADR.
Filtration - Alen T500 air purifier runs on a 3-stage filtration setup you should be acquainted with now. The pre-filter traps large airborne particles like dust, fur, and hair while extending the HEPA filter lifespan. The pre-filter is washable, so no replacement is needed unless it is damaged. The default HEPA-Pure filter traps fine particles that bypass the pre-filter as small as 0.3 microns. To deal with odor, smoke, and chemical fumes, you need to upgrade the filter to HEPA-Fresh or our favorite HEPA-OdorCell filter. For mold and germs-related allergens that are causing you to fall sick, opt for HEPA-Silver instead. Lastly, the safe ionizer diffuses negative ions to bond with positive ion pollutants in the air. the bonded ions will fall down due to the increased weight, and Alen T500 will draw in the unwanted contaminants for filtration.
Pricing - For a shy of under $200-250, Alen T500 is the cheapest release from the brand. You're getting exactly what it is designed for; a true HEPA air purifier in a compact form. If you can live with a bigger unit, Alen Flex, FIT50, or 45i would be a worthy upgrade. The $44-88 filter replacement cost might be the biggest obstacle for some, as other more maintainable air purifiers utilize a much cheaper filter set. If you could live with the annual filter cost and lack of autonomous mode, Alen T500 would be a good buy to kick start your air-purifying journey.
What To Look For In Alen Air Purifiers?
As every model varies in air cleaning performance, picking the right Alen air purifier is important as it is designed to last for a lifetime. To help you identify which air purifier works best in improving indoor air quality based on your needs, here are the features you to consider when buying one.
- Dimension and design - Pick something that you are comfortable pacing and using at home. Alen air purifiers come in a few different types and sizes that cater to all segments. Opting for BreatheSmart models, you have the luxury of customizing the front panels to suit your home decor.
- Weight and portability - Not known for its compact form or travel-friendly size, a typical Alen air purifier weighs between a reasonable 12-21 pounds. You can still move it with minimal effort by grabbing it on the back handle.
- Pricing - Other than the T500, that is priced under 200 dollars, Most BreatheSmart models will set you back between 399 to 750 dollars. Still, the value and performance Alen air purifiers bring to the table are unmatched. Discounts are scarce that usually happen during holiday seasons e.g. Summer sales, and Black Friday.
- Filter replacement cost - Depending on the filter grade, Alen filter costs range from reasonable to expensive, depending on which type of filters you go for. We highly recommend you upgrade the basic filter with an activated carbon filter to deal with smoke particles.
- Room size - Air cleaning coverage is never an issue with Alen air purifiers. All BreatheSmart models can cover large room sizes with at least 2 air changes per hour. If you intend to use it as a whole-room air cleaner, go with a bigger model or refer to the manufacturer's recommended room size.
- Clean air delivery rate (CADR) - The higher the ratings, the faster clean air can be achieved. CADR is AHAM developed metric that measures the air cleaning capacity of an air purifier in cubic feet per minute (CFM). Note that not all Alen air purifiers participate in the CADR test.
- Multi-stage air filtration - Alen air purifiers come standard with a permanent pre-filter, True HEPA filter, and an ionizer. The long-lasting H13 True HEPA filter is certified with 99.99% air particle removal efficiency down to 0.1 microns. A standalone activated carbon filter is optional but highly recommended.
- Noise and power consumption - Alen air purifiers are suitable for night use as reviewed by SleepScore Labs. However, it is not completely silent, especially when running on turbo speed. The same applies to energy usage; you can achieve maximum efficiency only with Auto mode enabled.
- Supporting features - Newer Alen air purifier models are packed with practical functions that would greatly enhance usability. Standard features include a Smart sensor, Auto mode, timer, air quality indicator, child lock, and filter change indicator. Premium features include WiFi-enabled support and remote control.
- Warranty and after-service - Alen will stand by their air purifiers for life. Every model is backed by a lifetime warranty with online registration and an active filter subscription. Customer satisfaction is also great with local support via phone or email.
Where Are Alen Air Purifiers Made?
Founded by Peter Mann in 2005, Alen Corp is an Austin, Texas based company that believes wellness begins with pure air. Award-winning Alen air purifiers are made in the U.S. and are fully customizable to address indoor air quality concerns. Alen offers a safe, innovative, and industry's pioneer lifetime warranty and is rated the #1 in-house customer care expert. With an Alen air purifier, you will enjoy healthy, worry-free, pure air for life.
Why Is My Alen Air Purifier Beeping Or Always Red?
Beeping noise and red light indicate that Alen air purifiers require filter change. Replace the filter and reset the Alen air purifier to rectify it.
How Do I Reset Alen BreatheSmart Light?
After replacing a brand-new Alen HEPA filter, you can reset the filter indicator by pressing and holding the filter light button for 5 seconds with the air purifier on. The filter light should transit back from red to green. Repeat the step every time the filter change indicator light turns red.

Is Alen BreatheSmart Worth It?
All Alen BreatheSmart air purifier is good value for money, particularly with the superior lifetime warranty. It comes with a washable pre-filter, a True HEPA filter, an activated carbon filter, and an ionizer. The air cleaning performance and room size coverage are also excellent for its class. You're also getting tons of features, including a timer, AQI, and auto mode. The ideal air purifier for long-term investment.
How Does Alen Purifier Work?
Using a multi-stage air filtration, air will be pulled in, and PM10 particles will be blocked by the pre-filter from passing through. The HEPA filter captures microscopic particles in the air, and the optional carbon filter absorbs smoke, odors, and toxic fumes. The ionizer emits positive and negative charged ions that cause the airborne pollutants to stick together and fall for the Alen BreatheSmart air purifier to capture.
How Do I Reset My Alen Air Filter Light?
When the filter change indicator light turns red, it is time to replace the filter. Remove the existing filters and replace them with a brand-new filter set. Turn on the air purifier, press and hold the filter button for 5 seconds to reset the filter indicator light back to green.
How Long Do Alen Air Purifier Filters Last?
Alen BreatheSmart HEPA filters can last 6 to 18 months, depending on indoor air quality and operational hours (8/ 12/ 24 hours a day). For heavily polluted areas, Alen recommends changing the filter every 6 months to ensure the best filtration performance, an endless supply of healthy air, and extend the usage life of your air purifier.
What Do The Colors Mean On Alen Air Purifier?
The 3 colors displayed in the air quality indicator hold different information:
- Blue/ Green = clean air with a low concentration of airborne particles.
- Yellow or purple = Moderate concentration of airborne particles.
- Red = Polluted air with a heavy concentration of airborne particles.

Which Alen Filter Is Best?
The best pick would be HEPA fresh filter, which offers great smoke and odor filtration at the lowest cost. Depending on the models, you could also opt for HEPA-Silver, HEPA-Pet, HEPA-FreshPlus, HEPA-OdorCell, or HEPA heavy odor filter. As for air purifiers, Alen BreatheSmart 75i is the best BreatheSmart model, with a max airflow of 347 CFM and a cleaning coverage of 1,300 square footage. It is quiet, versatile, and packed with tons of practical features.
Can You Wash Alen Filter?
Yes, the pre-filters attach to your HEPA filter via Velcro strips are removable and washable. It is made of mesh fabric layers that trap larger particles like dust and hair. However, we recommend vacuuming it rather than washing it to prevent it from getting damaged. Clean it every 1-3 weeks or when necessary. Both the HEPA and carbon filters are not washable.
Do Alen Air Purifiers Create Ozone?
All Alen Air Purifiers are ozone-safe, as certified by the California Air Resources board (CARB) and Food and Drug Administration (FDA). It uses mainly HEPA filtration that produces ozone emission concentrations of under 0.050 parts per million (ppm). The ozone emission level is so low that it will not cause chest pain, coughing, throat irritation, shortness of breath, and lead to respiratory illnesses and asthma. You can turn off the ionizer if you are uncomfortable using it.
How Do You Change The Filter On Alen BreatheSmart?
To replace your Alen BreathSmart filter, start by:
- Unplug the air purifier from an electric outlet.
- Pull out the magnetic-clipped cover with both hands.
- Remove the used filter carefully by pulling the tab. Dispose it properly to prevent captured particles from escaping.
- Remove the plastic sleeves from the new filter set, then carefully insert the filter into the air purifier.
- Clip back the cover and plug the Alen air purifier into a ground outlet. If it is running smoothly, the filter change is complete.
Is It OK To Leave Alen Air Purifier On All Night?
Yes, it is OK to leave an Alen air purifier on all night during sleep. Alen BreatheSmart is meant to run 24/7, so you can enjoy constant clean air. If you turn off the device, dirty air will quickly return and pollute the indoor air. With the increased amount of air particulates trapped, check on the filters from time to time to see if replacements are needed.
How Much Energy Do Alen Air Purifiers Use?
It greatly depends on the model. Most Alen air purifiers are energy-efficient that use 30-60 watts of electricity. Alen's operating cost is estimated to be around $3-6 monthly with 12 hours of daily operation. Multiply by 12, and the electricity costs are about $36-60 annually.
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Compare Alen Air Purifiers
No | Image | Air Purifier | Online Price (Amazon) | Score | Filtration | Coverage | Fan Speed | Dimension | Weight | Dust CADR | Pollen CADR | Smoke CADR | Pre-filter | HEPA filter | Carbon filter | Ionizer | UV light | Other filter | All-in-one filter | Noise level | Power output | Timer/ Scheduler | Sensors | Warranty | Auto mode | Remote control | Child lock | ENERGY STAR | Wi-Fi/ BTBluetooth | AQI | Filter indicator |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | ![]() | Alen BreatheSmart Classic Air Purifier | $$$$$$$ CHECK PRICE | 4.5 | 3-stage | 1,100 sq. ft. (102 m2) | 4 | 17.8 x 26.8 x 10 in (45.2 x 68.1 x 25.4 cm) | 21 lb (9.5 kg) | 300 cfm (510 m3/h) | 300 cfm (510 m3/h) | 300 cfm (510 m3/h) | Washable Pre-filter (with HEPA filter) 6 - 18 months | HEPA-Pure Filter BF35 6 - 18 months +- 69 | - | Ionizer | - | - | - | 42-56 dB | 64 - 105 W | 4, 8, 12 hours | SmartSensor | Lifetime Limited Warranty | |||||||
2 | ![]() | Alen BreatheSmart 75i Air Purifier | $$$$$$$ CHECK PRICE | 4.6 | 3-stage | 1,300 sq. ft. (121 m2) | 5 | 18.5 x 27 x 11.5 in (47 x 68.6 x 29.2 cm) | 27 lb (12.2 kg) | 347 cfm (590 m3/h) | 347 cfm (590 m3/h) | 347 cfm (590 m3/h) | Washable Pre-filter (with HEPA filter) 12 - 18 months | Pure Antimicrobial True HEPA Filter B7-Pure 12 - 18 months +- 99 | - | Ionizer | - | - | - | 25-49 dB | 1.8-45 W | 2, 4, 12 hours | Intelligent sensor | Lifetime Limited Warranty | |||||||
3 | ![]() | Alen BreatheSmart 45i Air Purifier | $$$$$ CHECK PRICE | 4.2 | 3-stage | 800 sq. ft. (74 m2) | 4 | 15 x 25 x 8.5 in (38.1 x 63.5 x 21.6 cm) | 15 lb (6.8 kg) | 245 cfm (416 m3/h) | 245 cfm (416 m3/h) | 245 cfm (416 m3/h) | Washable Pre-filter (with HEPA filter) 6 - 18 months | HEPA-Pure Filter FL40 6 - 18 months +- 59 | Ionizer | - | - | - | 23-49 dBA | 50 W | 2, 4, 12 hours | Intelligent sensor | Lifetime Limited Warranty | ||||||||
4 | ![]() | Alen BreatheSmart FIT50 Air Purifier | $$$$$$$ CHECK PRICE | 4.2 | 3-stage | 900 sq. ft. (84 m2) | 4 | 16.8 x 22.3 x 10 in (42.7 x 56.6 x 25.4 cm) | 16 lb (7.3 kg) | 220 cfm (374 m3/h) | 220 cfm (374 m3/h) | 220 cfm (374 m3/h) | Washable Pre-filter (with HEPA filter) 6 - 18 months | HEPA-Pure Filter FF50 6 - 18 months +- 79 | - | Ionizer | - | - | - | 32 - 49 dB | 60 W | 2, 4, 12 hours | SmartSensor | Lifetime Limited Warranty | |||||||
5 | ![]() | Alen BreatheSmart FLEX Air Purifier | $$$$ CHECK PRICE | 4.1 | 2-stage | 700 sq. ft. (65 m2) | 4 | 15 x 25 x 8.5 in (38.1 x 63.5 x 21.6 cm) | 15 lb (6.8 kg) | 245 cfm (416 m3/h) | 245 cfm (416 m3/h) | 245 cfm (416 m3/h) | Washable Pre-filter (with HEPA filter) 6 - 18 months | HEPA-Pure Filter FL40 6 - 18 months +- 59 | - | - | - | - | 39 - 55 dB | 36 W | 2, 4, 12 hours | Lifetime Limited Warranty | |||||||||
6 | ![]() | Alen T500 Air Purifier | $$$ CHECK PRICE | 3.9 | 3-stage | 500 sq. ft. (46 m2) | 3 | 10 x 22 x 6 in (25.4 x 55.9 x 15.2 cm) | 9 lb (4.1 kg) | 159 cfm (270 m3/h) | 159 cfm (270 m3/h) | 159 cfm (270 m3/h) | Pre-filter Permanent | HEPA-Pure Filter TF60 6 - 12 months +- 44 | - | Ionizer | - | - | - | 42 - 56 dB | 30 - 53 W | 12 hour timer | SmartSensor | Lifetime Limited Warranty |
