Alen BreatheSmart 45i Quick Review

Think about it as an upgraded version to Flex, Alen BreatheSmart 45i is THE favor of the month with extended purifying coverage and improved airflow circulation against airborne microorganisms and allergens. On top of existing Alen trademark lifetime warranty and personalizable front panel, Alen BreatheSmart 45i provide exceptional value for a pet owner or asthmatic patient that is frequently impacted by airborne irritants. Comparing the BreatheSmart series on airflow delivery rate, applicable radius, noise level, and power consumption, what newer features can you expect from Alen BreatheSmart 45i air purifier?
± 429 p
     Annual filter ^    
± 39 - 118 p
 Online price*
** MRSP (Manufacturer's Suggested Retail Price)/ RSP (Retail selling price) is provided by cleanairprice.com. Accurate at the time of posting.
^ Annual filter cost is calculated based on filter price and 12 hours of usage. Pricing could vary depending on air quality, usage frequency, and speed.

Alen BreatheSmart 45i Specification

ProductAlen BreatheSmart 45i
15 x 25 x 8.5 in
(38.1 x 63.5 x 21.6 cm)
Weight15 lb (6.8 kg)
Coverage (up to)800 sq. ft. (74 m2)
Airflow speed53 - 190 cfm (90 - 323 m3/h)
Dust free (CADR)245 cfm (416 m3/h)
Pollen free (CADR)245 cfm (416 m3/h)
Smoke free (CADR)245 cfm (416 m3/h)
- Lifespan
- Replacement cost ($)
Washable Pre-filter (with HEPA filter)
6 - 18 months
HEPA filter
- Lifespan
- Replacement cost ($)
HEPA-Pure Filter FL40
6 - 18 months
+- 59
Carbon filter
- Lifespan
- Replacement cost ($)
Ionizer/ TechnologiesIonizer
UV-light/ PCO
Other filter
All-in-one filter
- Lifespan
- Replacement cost ($)
Optional/ Addon
6 - 18 months+- 79
HEPA-OdorCell Filter FL40-MP
6 - 18 months+- 89
HEPA-Fresh Filter FL40-CARBON
6 - 18 months+- 69
Noise level55 dB
Power usage level50 W
Timer/ Scheduler2, 4, 12 hours
SensorsIntelligent sensor
Auto mode
Air qualityAQ indicator
Filter change indicator
More color options
Wi-Fi/ BTBluetooth
Remote control
Child lock
WarrantyLifetime Limited Warranty
Email/ Phone support

Key features

  • 3-stage filtration with ionizer
  • Washable pre-filter/ HEPA-Pure filter - [Optional] HEPA-Silver filter, HEPA-FreshPlus filter, HEPA-OdorCell filter
  • 4 fan speeds with auto mode/ lights-off mode
  • Smart Filter Light indicator
  • intelligent sensor technology
  • Personalizable front panel design
  • Generate soothing pink noise frequency to enhance sleep up to 25% better
  • Child-lock control panel and child-safe vent guard
  • 4, 8, 12 hour Pre-set timer
  • Forever guarantee warranty


  • As always, there is no shortage of front panel design to choose from.
  • Even wider purifying coverage with superior airflow distribution.
  • Customizable filter with up to 3 optional filter upgrade.
  • Ionizer is ozone-free and can be easily turn on or off.
  • Uses the same Flex filter that is proven and long-lasting (up to 18 months).
  • Newer intelligent sensor that powered the air purifier auto/ lights-off mode.
  • Like most Alen newer air purifiers, you can easily lock 45i controls from your child.
  • Air purifier is guaranteed for life from any manufacturer's defect.


  • Lacks chemical/ odor filtration on the standard HEPA-Pure filter.
  • The 1 filter setup is easy to use, but lacks the filtration depth to compliment the HEPA filter in particle capture.
Alen BreatheSmart 45i has all the elements of previous BreatheSmart generation design, durability, and features for an owner that requires absolute familiarity. Zero gaps between its simpleness body originate from the smooth and well-defined framework. In the meantime, the control panel is flawlessly attached and ergonomically placed to permit seamless usage. No noticeable off-gassing on Alen BreatheSmart 45i high-grade structure that would impact the solidity of the air purifier. The forever guarantee assurance will allow people to continue using the air purifier frequently without having to worry it would wear out.

Airflow efficiency and purifying coverage

The justification why Alen BreatheSmart 45i is the improved version. An air purifier that is appropriate for a roomy home, at a significant wider applicable area, the overall airflow delivery is amazing. Generally, places such as living room, office or master bedroom would very likely compliment Alen BreatheSmart 45i best.

Furthermore, Alen BreatheSmart 45i supportive airflow input and output is incredible at wiping off nearby air-borne particles. One example to demonstrate the air purifier effective purifying is nearby airborne particles e.g. dust, pet dander, pollen, mold, mildew, and fungus would all be fully taken up and captured.

Noise level and power consumption

Alen BreatheSmart 45i specifically built framework is outstanding at diminishing noise developed from the fan to a minimum level. Noise level is rather soft at low/ medium fanspeed and as expected high at fanspeed. When compare to other common household appliances, Alen BreatheSmart 45i noise level is still within a justifiable rate.

In the meantime, Alen BreatheSmart 45i cost-saving airflow purifying would save you tons of money on utility bills in long run. Electricity consumption is quite minimal at low fanspeed and needless to say will jump at higher fan speed. Alen BreatheSmart 45i power usage is marginally lesser when put next to other fairly equivalent household appliances.

noise graph

Final thoughts on Alen BreatheSmart 45i

To sum up, Alen BreatheSmart 45i is what a marvelous air purifier would be. Compare with the entire list of strong points and weak points, the added merits make certain the drawbacks have zero outcomes on the air purifier efficiency. Combined the 2 highlights above, we have no reservations strongly recommending Alen BreatheSmart 45i.

At what cost

Alen BreatheSmart 45i MRSP/ RSP
+- 429
Alen BreatheSmart 45i annual filter replacement cost
Annual Filter Cost
+- 39 - 118
^ Replacement filters/ estimated cost
SPA-550A is the least expensive in Rabbit Air BioGS and MinusA2 series; not so much so when compared with other similar high purifying range air purifiers from Winix, Honeywell. While CADR figures are not overly impressive, you do receive a great deal of premium features as standards like Auto mode, air quality sensor, timer and remote control (with holder). On the other end, annual filter replacement cost is close to flawless as the filter lifespan is lengthy (up to 3 years) and can be purchased in a bundled replacement kit. For the filter maintenance factor alone, Rabbit Air SPA-550A will be well worth the purchasing price in long-run.
As mentioned earlier, competitors model like Winix NK105/ HR1000, Alen BreatheSmart series or Blueair 205 offer wider purifying coverage and better CADR with a cost. If you already decided on BioGS 2.0, Rabbit Air SPA-550A has a fixed price regardless from channels like Bestbuy, Overstock or official website. As we are part of Amazon affiliate, you can support us by purchasing from Amazon that comes with free shipping and 30-day no questions asked return policy. Alternatively, you can consider purchasing from Rabbit Air's website (again no discount) that add the merits of 90-day money back guarantee and stock availability assurance. Finally, all official, non-import Rabbit Air purchase comes with 24x7 technical support/ customer service and a 5 years official manufacturer warranty.

Alen BreatheSmart 45i VS the challengers

Rabbit Air BioGS 2.0 SPA-625A

Rabbit Air BioGS 2.0 SPA-625A

As the model name rightly pointed, this is the higher version of BioGS series that offers better airflow performance and coverage (625 VS 550 sq.ft.) with a minor price increase. Everything else is exactly the same.
Honeywell HPA300

Honeywell HPA300

Another popular alternative in the list, Honeywell HPA300 is cheaper with better CADR performance than Rabbit BioGS. In long-run though, the higher filter replacement cost and less filtration depth might come back to haunt you.
Rabbit Air MinusA2 SPA-700A

Rabbit Air MinusA2 SPA-700A

Space-friendly, swappable front panel, 6-stage filtration (medium + customized filter), wider purifying coverage and of course better overall CADR. Rabbit Air MinusA2 is no doubt the upgrade both aesthetically and functionality at a premium cost.
Winix 5500-2 PlasmaWave

Winix 5500-2

Our highly recommended air purifier that is well-rounded in terms of pricing with performance ratio. Winix 5500-2 also has an identical setup as Rabbit BioGS in dimension, practicality features and filtration performance. The main differences between the 2 are BioGS has a much lower filter maintenance cost while 5500-2 gain a much lower price point.

Final thoughts on Alen BreatheSmart 45i

If you are looking for an air purifier that will do a fantastic job in alleviating common household pollutants, smokes and odors, look no further. As the positive review clearly outweigh the cons in Amazon reviews, 92% of them leave an exceedingly positive 4 – 5 stars. Users like Rabbit Air SPA-550A top-notch build quality, consistent performance with effective four-stage filtration, reliable customer service and economical operating cost from the prolong filters lifespan. The remaining 5% that leave a neglectable 1 - 2 stars is experiencing poor filtration performance mainly on smoke and odors. If we have to pick a bone with this air purifier, its older brother (SPA-625A) offers a better deal in terms of price ratio.

Verdicts and ratings

Build quality
Particle Filtration
Smoke Filtration
Alen BreatheSmart 45i

Max Fernandez

A loving father and a dedicated reviewer for airfuji.com with more than 1000 air purifiers under his belt. Max Fernandez is also one of the million patients currently suffering from asthma. Feel free to nudge him if you have any questions.

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