In this post, we’re going to be looking at two excellent air purifiers; The Alen BreatheSmart 45i, and the Alen BreatheSmart 75i.
Now, there’s a good chance you’ve never actually heard of Alen or the Alen BreatheSmart product line. They aren’t exactly the most popular brand of air purifier, and there is a good reason for that.
Alen manufactures Air Purifiers that are top-of-the-line. These are some of the best and most advanced air purifiers that you can find in today’s market. However, this means two things.
First, most people don’t need something this advanced, so they don’t have the same overall popularity as other air purifiers that are designed for more common use.
Second, they’re expensive. Neither of the air purifiers we’re going to be looking at in this comparison article is cheap.
If you want the best of the best, though, then this is the best article you can be reading, because these air purifiers are legitimately some of the best on the market.
Before, we get into that, though, as a refresher, let’s go over what an Air Purifier does and why it is so essential.
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Alen | 45i | 75i |
Weight | 23.6 pounds | 35 pounds |
Power Source | 120V | 120V |
Item Dimensions | 15 x 8.5 x 25 in | 15 x 23 x 30.75 in |
Floor Area | 800 Sq Ft | 1,300 Sq Ft |
Filters | 2 | 4 |
Ionizer Feature | Yes | Yes |
Power Consumption | 50 Watts | 45 Watts |
Filter Life | 9-12 Months | 12-15 Months |
The Air Purifier
An air purifier is a device that sits in a room. The air in this room is then sucked into the air purifier, where it undergoes a process known as “purification.” This purification process can take many different forms because there are many different methods of purification, but by the end of the process, the air is clean. There are no more germs or allergens, and the air is safe to breathe.
Why Do I Need An Air Purifier?
If you suffer from things like asthma, or any type of respiratory disease, an air purifier is a necessity. These simple devices provide so much relief to your body because they eliminate the particles that can heighten and intensify the difficulties of things like asthma, along with other respiratory conditions.
Along with that, air purifiers are great for removing nasty odors and smells. As well as removing pollutants, basic allergens, and, in general, providing a far cleaner and healthier home for yourself.
Alen BreatheSmart 45i
Right off the bat, you’ll notice how sleek, and compact the Alen BreatheSmart 45i air purifier is. Now, it does weigh 24 pounds, but everything is designed in such an aesthetically pleasing and compact way, that the weight doesn’t matter.
Due to the design of the 45i, it takes up very little space, yet it has every feature you could ever want in an air purifier. There is also the presence of a technology known as “WhisperMax”, which is a proprietary technology that is designed to reduce the noise the purifier makes. This makes it perfect for many different types of spaces.
As for the maximum area coverage, it is 800 feet.
Using laser sensors, the 45i detects the particles that are in your air, down to 0.3 microns. Then, the device feeds this information into the filter, enabling it to adjust, on the fly, to accommodate the needs of your air. That way, you don’t have to change anything manually. And, this information is displayed on a small LED display.
Finally, regarding what the 45i can purify, it uses a HEPA-Silver filter. This filter can eliminate things like mold, dust, bacteria, chemicals, and odors. Using an antimicrobial compound that the filter is coated with, the growth of things like bacteria and fungi is inhibited. Odors are also eliminated through the use of carbon that is designed to absorb specific odors.

Alen BreatheSmart 75i
When comparing the Alen BreatheSmart 45i with the Alen BreatheSmart 75i, it becomes apparent that there aren’t too many distinct differences.
One of the most notable differences is that the 75i has a maximum area coverage of 1300 square feet. This is an extra 500 square-feet, in comparison to the 45i.
Along with that, the WhisperMax technology on display here is a bit better than that of the 45i, because it enables the 75i to produce even less noise, even though it is working a bit harder, due to the difference in maximum area coverage.
Related Alen Air Purifier ArticlesSingle Reviews
Alen BreatheSmart 45i
Alen BreatheSmart 75i
Alen BreatheSmart Classic
Alen BreatheSmart FIT50
Alen BreatheSmart FLEX
Comparison Articles
Alen BreatheSmart 45i vs. 75i
Alen BreatheSmart vs. Rabbit Air MinusA2
Alen BreatheSmart FLEX vs. FIT50 vs. 75i
So, Which One Should I Buy?
If you have a room that is smaller, or just barely above, 800 square-feet, then the 45i is more than sufficient for your purposes. But, it does give you less flexibility, overall.
With the 75i, you have that extra flexibility, and it’s a quieter machine. But, there is a significant price increase, so keep that in mind.

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Last update on 2021-01-21 / Most affiliate links and/or Images from Amazon Product Advertising API