Alen BreatheSmart 45i vs. Alen BreatheSmart 75i HEPA Air Purifier

Alen BreatheSmart 45i vs. Alen BreatheSmart 75i

Indoor air quality is an important element of any home. It ensures that you are comfortable and at peace in your own home. However, maintaining a safe and comfortable indoor environment with clean air should not be something that you actively take part in. It should be something that you don’t think about. With this in mind, your air purifier should be a device that does exactly that: gives you clean indoor air without requiring a lot of your input.

Alen BreatheSmart air purifiers are popular for doing a decent job purifying indoor air. They are simple, elegant, but effective in their job. Today, we will compare the Alen BreatheSmart 45i and the BreatheSmart 75i to try and establish which of the two would be best suited for the job.

Since both these air purifiers are in the Alen BreatheSmart line of products, you will find that a lot of their traits and features are closely related. In fact, a majority of the differences you will find between these two devices are more of capacity differences and not big feature differences.

With that said, let’s dive in.

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Alen BreatheSmart 75i vs. Alen BreatheSmart 45i


Alen BreatheSmart 45i
This air purifier looks simple, but that does not mean that it is boring. You get plenty of face designs to choose from to ensure that it blends perfectly with your home’s interior. The frame has been designed to save space without affecting the purifier’s performance to ensure that you get a sleek, modern and functional package that fits perfectly in tight spaces.

The control panel is on the top of the unit, and it comes with all the functions that you need to monitor and regulate your indoor air quality.

Alen BreatheSmart 75i
Despite the fact that this air purifier is capable of cleaning larger rooms than the 45i, it is compact enough to fit in reasonably small spaces. It also comes in a number of faces to ensure that you pick one that fits perfectly in your home.

As you would expect, the 75i is larger and heavier than the 45i, but this also means that it is more powerful and capable of cleaning larger areas. Other than the difference in overall dimensions and weight, the 75i is pretty much similar to the 45i when it comes to the design.

Alen BreatheSmart 45i Air Purifier

Cleaning Stages

Alen BreatheSmart 45i
This is a 3 stage air purifier which means that the air is kept clean while ensuring that the HEPA filter lasts long. Before going through the HEPA filter, air is passed through the pre-filter that absorbs the larger particles thus ensuring that the air that is sent to the HEPA filter is free from a majority of impurities.

This way, only the finest and smallest particles make it to the more expensive HEPA filter so it will be a while before you need to hit the stores for a replacement. The pre-filter is washable; hence you don’t need to worry about replacement costs.

The third stage is an ionizer that will remove dust, bacteria, and allergens from the air without using any filters.

Alen BreatheSmart 75i
This air purifier also comes with a washable pre-filter, a HEPA filter, and ionizer. However, the filters here are larger than those found in the 45i to accommodate the higher airflow speed as a result of the higher capacity.

Alen BreatheSmart 75i Review

Noise Production

Alen BretheSmart 45i
In any air purifier, the fan is responsible for forcing the air through the filters for cleaning. As this happens, some noise is produced. This noise varies depending on the fan speed and the design of the blades.

In the 45i, the entire system has been designed to give you the best airflow without disturbing your peace. This air purifier has 4 fan speeds that produce a maximum noise level of 55 decibels. If you don’t want to keep the unit running the whole time, you can use the timer to delay starting of the unit by 2, 4 or 12 hours. This way, you can come home and enjoy a clean and comfortable environment without having to be present while the cleaning is being done.

That’s not all. Despite the low maximum noise levels, you can take it a notch higher with the lights-off mode. This mode is specially designed to give you a peaceful night’s sleep without compromising on air quality. The objective is to clean your air without disturbing your sleep so the fan is as silent as possible and the light on the display panel are off.

Alen BreatheSmart 75i
Since it is larger, more capable and more powerful than the 45i, most people would expect this air purifier to produce more noise because of the higher performance. This is not the case. Despite being more powerful, the 75i is actually more silent than the 45i.

With maximum noise levels of 49 decibels, this air purifier is able to clean larger rooms while working faster than the 45i and producing less noise by 6 decibels. It also comes with 4 fan speeds so that you can find a balance between performance and noise levels, a 2, 4 or 12-hour timer, and a lights-off mode that cleans your air as you sleep without disturbing your sleep.

Alen BreatheSmart 45i


Alen BreatheSmart 45i
When buying an air purifier, one big consideration is the coverage. It is important to pick a device that will be able to clean the entire room that you intend to use it in. On the one hand, you don’t want to spend too much money on an air purifier made for large rooms when a small one can do the job.

On the other hand, you don’t want to buy one designed for small rooms when you have large rooms because no matter how hard it works, it will never be able to deliver a 100% clean and fresh smelling interior.

The Alen BreatheSmart 45i is intended for rooms with an area of up to 800 square feet. This means that the device will have no problems purifying the air in rooms with a floor space of up to 800 square feet.

Alen BreatheSmart 75i
As mentioned earlier, this one is much more capable than the 45i. It has been built to purify the air in rooms as big as 1300 square feet in 30 minutes. This means that in a 1300 square foot room, the air is purified twice every hour when the purifier is on.

This means that impurities will be quickly eliminated even if they come in rapidly.

Alen BreatheSmart 75i Air Purifier

Related Alen Air Purifier Articles

Single Reviews
Alen BreatheSmart Classic
Alen BreatheSmart 45i
Alen FIT50
Alen BreatheSmart 75i
Alen BreatheSmart FLEX

Comparison Articles
Alen BreatheSmart Classic vs. 75i
Alen BreatheSmart 45i vs. 75i


Both these air purifiers are made with very closely related features and abilities. The biggest difference is in the fact that the 75i is capable of covering larger spaces with an area of up to 1300 square feet while the Alen 45i is capable of purifying rooms with an area of up to 800 square feet.

So the Alen BreatheSmart 75i is your best choice if you have large rooms. However, you can save some money with the 45i if you have small and medium-sized rooms. The 45i comes with pretty much the same features and functionality but with lower coverage and a lower price tag.

Alen BreatheSmart 45i Review

Air Purifier | Bestseller

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Last update on 2021-05-11 / Most affiliate links and/or Images from Amazon Product Advertising API

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