Alen FLEX Air Purifier Review: Sufficient & Powered

Alen, an iconic American company located in Austin, has been paving the way for modern air purification with their BreatheSmart FLEX. A marvel of craftsmanship and design that sets a new standard when it comes to efficient performance in a sleek minimal form factor that can fit any room up to 300 sq. ft., this is truly one of the best air purifiers available on today’s market – outperforming its predecessor by leaps and bounds!

I have had my eye on Alen’s air purifier market for a while now and was eager to put some of their products to the test. Primarily, I wanted to assess whether or not the BreatheSmart FLEX lives up to its lofty reputation garnered by user reviews.

The Alen FLEX air purifier stands out from its peers: crafted with care, presented in a premium package, and boasting an attractive design. For those seeking the best quality for their homes, this impressive model won’t disappoint.

Alen Flex air purifier Summary

  • The Alen BreatheSmart FLEX offers an ideal purification solution for mid-sized areas, efficiently cleansing up to 300 sq. ft. of air in your home or workspace!
  • Delivering whisper-quiet operation with outstanding performance and energy efficiency, the FLEX is a top-of-the-line device.
  • Ideal for bedrooms, basements, living rooms, or any medium-sized space – this product is unbeatable!
  • Alen proudly provides an unbeatable lifetime warranty on this product, ensuring your satisfaction and peace of mind.
  • A variety of filtering options to suit your preferences.

Best Air Purifier for performance

Alen FLEX Air Purifier

The Alen BreatheSmart FLEX air purifier is both aesthetically pleasing and highly effective, providing clean air to rooms of up to 300 sq. ft in size or even smaller spaces without the need for steam.



Manufacturer Alen
Model BreatheSmart FLEX
Dimensions 8.5 x 15 x 25 inches
FiltersPre-filter, True HEPA Filter and Activated Carbon Filter
Filter Longevity9-12 months
Number of Fan Speeds4 – Speed 1, Speed 2, Speed 3, and Turbo Mode
Coverage300 sq. ft.
Power Consumption50W

Design and Size




  • Color: White
  • Product Dimensions: 8.5″D x 15″W x 25″H
  • Item Weight: ‎15 Pounds
  • Control Method: Touch
  • Wattage:Ac/dc

Experience a new level of air purification with the Alen BreatheSmart FLEX. The mid-size device has an undeniably luxurious look and feels, made from a robust plastic that boasts superior build quality when compared to similar models in its class.

Plus, generous dimensions make room for a more powerful motor and larger filter – so you know your home or office space is receiving truly thorough cleaning capabilities whenever it’s on!

Alen FLEX is a marvel of modern design, crafted with eye-catching aesthetics and impressive build quality. Its 78 cm power cord cable adds to its convenience while the choice of 6 color options caters to all types of preferences – whether you prefer espresso or brushed stainless, graphite or oak, weathered grey or white. I personally went for the subtle yet chic look that only Alen Flex’s “white” shade can provide!

Control Panel

At the top is Alen’s control panel, adorned with 5 touch keys and its graceful logo. The power button – the largest of all five – occupies center stage here; it is arguably the most essential key on this board as pressing it kickstarts your device.

Not only that, but the second press of this button dims all LED indicators- a useful feature for those who plan to use the device in their bedroom. When powered on, you will notice a bright blue light surrounding the power button.

Located on the far left is the filter button, labeled with a sign displaying how much use it has seen. Just next to that is a timer button exhibiting its own gauge of performance.

Furthermore, the speed button allows you to quickly toggle between four different speeds.

Lastly, there’s the lock button which ensures all other buttons won’t be activated or switched off unintentionally.

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Alen FLEX is a powerful air purifier that aims to bring simplicity and convenience into your home. Though it lacks certain advanced features, such as auto mode or smart sensors found in pricier models, what you do have here are reliable quality and dependable performance – making the Alen FLEX an unbeatable value for its category.

Switching off the indicator on the device

Alen FLEX provides a simple way to turn off the device’s indicator lights: simply press the power button when the air purifier is on. This will deactivate all indicators and switch off your Alen FLEX for good. Each time you need to use it again, just repeat this process and enjoy fresh, clean air!


A timer is an invaluable tool, especially for Alen since it’s the only option to “program” its operating mode. Without a timer, Alen would be out of luck. With the timer activated, the Alen FLEX will automatically shut off after a preset period of two hours, four hours, or twelve hours.

Filter Reset Indicator

With the innovative filter reset indicator on FLEX, you’ll never have to worry about when it’s time to swap out your air purifier filters again. You won’t need an external reminder or calendar because this device will let you know exactly when a new filter is needed!

A trio of round indicators should appear above the “Filter” button, with only one indicator illuminated green when you first begin using the device. As soon as a yellow signal appears, it is time to consider changing your filter in preparation for replacement; once red indicates its presence, immediate action must be taken and the filter altered on your apparatus.

Control Panel Lock

If you have kids around the house, this is the ideal way to secure your device against accidental commands. This feature can keep toddlers from mistakenly shutting down or changing modes on your gadget.

Keep your finger pressed firmly on the lock button for a full 5 seconds to activate it. After that, no other buttons will be registered unless you start the process over again.


Alen BreatheSmart FLEX offers you the choice of three different filters, all with a fundamental True HEPA filter. The greatest variation between each one is in the activated carbon filter contained within them.

The optional filters are:

  • Dust, Mold, Pet Odors
  • Dust, Mold, Pet Odors + Smoke
  • Dust, Mold, Pet Odors + Heavy Smoke

After testing the device with its “Dust, mold, pet odors + smoke” filter installed, I was astounded by how effectively and efficiently it performed. It proved to be a truly optimal choice for my needs.


The pre-filter acts as the preliminary stage of filtration, safeguarding your True HEPA filter with a snug Velcro strap. It prevents larger particles such as pet fur and dander from penetrating the HEPA filter, substantially enhancing its useful life! Furthermore, you can easily detach it if necessary.

True HEPA Filter

True HEPA is the principal and most efficient level of filtration to purify the air. The BreathSmart FLEX utilizes a medical-grade H13 True HEPA layer that eliminates 99.99% bacteria, aerosolized viruses, and airborne particles larger than 0.1 microns from your environment!

Not only does this filter remove such matter but it also lasts 3-5 months longer than standard filters – making it the perfect investment for clean air in your home or office space!

Activated Carbon Filter

The final stage of filtration is the activated carbon filter. It’s this step that ensures gases, VOCs, and other foul smells are eliminated from the air – leaving your home smelling fresh!

Trust me, go with the carbon filter option to get full advantage of the Alen FLEX. This way, you’ll be well-equipped for any surprise scenarios.


The Alen BreatheSmart FLEX is the ideal air purifier for those in search of fresher, healthier living spaces. It can effectively tackle dust, mold spores, and much more from any room up to 300 square feet.

use the Flex air purifier on turbo mode for 1-2 hours while on the lowest speed and leave it for 24 hours and use it in busy spaces.

560 sq. ft. Room Test

Measuring 560 sq. ft, the first examination was conducted in a room slightly undersized compared to our suggested dimensions; however, I still proceeded with placing an Alen BreatheSmart FLEX and running it fully open.

In only one hour of operation, the FLEX drastically decreased air pollution by 94%, transitioning an AQI of 126 to 8. This is a remarkable result considering that the room in question was slightly smaller than what’s recommended.

Noise Test

The Alen BreatheSmart FLEX is an astonishingly peaceful device that I have never encountered before.

Although quiet, it still operates effectively and has been SleepScore certified; users report waking up feeling more energized each morning.

This air purifier truly is the ideal silent companion for any home or office!

The Alen FLEX comes with four-speed settings, making it easy to find the perfect one for your needs.

At its lowest level, it operates at a whisper-quiet 41.2 dBA – yet more remarkably, even when in turbo mode, the FLEX emits just 53.7 dBa! With a such comprehensive selection of speeds and sound levels available from this powerful device, you’ll be sure to find exactly what works best for you.

Speed Value (dBA)

Speed 1 41.2 dBA

Speed 2 43.5 dBA

Speed 3 48.9 dBA

Turbo Mode 53.7 dBA

Power consumption

The Alen BreatheSmart FLEX is a superb air purifier that requires only 50W to operate. If you keep it running constantly, the cost for one month of electricity in the US would be 2.1 USD—that’s based on an average rate of 0.12 USD/h!

Room Coverage 

Alen BreatheSmart FLEX boasts an impressive CADR score of 245, allowing it to surpass the average air purifier in its ability to eliminate small airborne pollutants with heightened efficiency.

Perfectly tailored to any area, ranging from bedrooms and living rooms to kitchens and offices – the Alen FLEX boasts impressive air purifying capabilities in spaces up to 300 sq. ft., with an ability to cleanse your environment twice every hour!

Pros & Cons

Easy to use
Provide your baby with the freshest air possible in her room.
Sleep mode should be ultra-quiet.
Best for large room
Not a portable friendly
No auto mode


The Alen BreatheSmart FLEX has certainly exceeded my expectations with its sleek design and outstanding performance. Not to mention, it achieved phenomenal scores on all tests! This device is truly a minimal masterpiece when it comes to air purification.

The Alen BreatheSmart FLEX air purifier is both aesthetically pleasing and highly effective, providing clean air to rooms of up to 300 sq. ft in size or even smaller spaces without the need for steam. Its sleek design complements any atmosphere while its efficient performance guarantees satisfaction with your purchase.

What is an air purifier?

An air purifier is a device that helps to remove impurities such as dust, allergens, and pollutants from the air. It works by using various filters and technologies to clean the air, making it healthier to breathe.

Who can benefit from using an air purifier?

Anyone can benefit from using an air purifier, but they are particularly helpful for people with allergies, asthma, or other respiratory conditions. They can also be useful for people who live in areas with high levels of air pollution.

How do I choose the right air purifier for my needs?

When choosing an air purifier, consider factors such as the size of the room where it will be used, the type of impurities you want to remove, and your budget. Look for models that are certified by reputable organizations such as the Asthma and Allergy Foundation of America.

Can air purifiers help to prevent the spread of COVID-19?

While air purifiers cannot completely prevent the spread of COVID-19, they can help to reduce the risk of airborne transmission. Look for models with HEPA filters, which can capture small particles such as the virus that causes COVID-19.

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The author is an Air purifier expert with overall knowledge of air and ionizers.