In this Alen BreatheSmart 45i vs 75i review, we will compare two of the most popular devices by the Austin, Texas-based company known for its high quality air purifiers.
Both models can be personalized not only in terms of filter capabilities, but also when it comes to the colour of the front panel. Both are backed by an unlimited warranty. So should you opt for the BreatheSmart 45i, or invest in the high-end BreatheSmart 75i?
This side-by-side comparison will help you find out.
Alen BreatheSmart 45i
Alen BreatheSmart 75i
Coverage Area
Up to 800 ft²
Up to 1300 ft²
CADR (Particles)
245 m³/h
347 m³/h
Power Consumption
1.1 – 50 Watts
1.8 – 45 Watts
Working Noise
23 – 49 dB(A)
25 – 49 dB(A)
PM 2.5 Sensor
Yes
Yes
Comparison: Alen BreatheSmart 45i vs 75i – What are the Differences?
Coverage Area
Alen recommends the BreatheSmart 45i for rooms with a surface area of up to 800 ft² (74 m²), while the suggested coverage area for the 75i stands at 1300 ft² (121 m²). In both cases, the numbers were based on an assumed two air changes per hour (ACH).
Winner: BreatheSmart 75i
Up to 800 ft²
Up to 1300 ft²
Clean Air Delivery Rate
Using a True HEPA filter, the BreatheSmart 45i and 75i are able to remove 99.9% of particles greater than 0.1 microns. It is even possible to choose a filter configuration depending on your exact needs, for example one especially effective against pet odours or one against smoke.
On the highest speed setting, the 45i purifies around 215 cubic feet per minute (CFM), resulting in a Clean Air Delivery Rate (CADR) of 245 m³/h. The 75i, on the other hand, goes through a maximum of 350 CFM and has a CADR of 347 m³/h.
Winner: BreatheSmart 75i
245 m³/h
347 m³/h
Working Noise
The BreatheSmart 45i and 75i both operate at 49 decibels (dB) when running at full speed. On the lowest speed setting, the 45i has a slight edge at just 23 dB compared to 25 dB for the 75i. In total, there are four different speeds for the 45i and five for the 75i.
Both models can be set to automatic mode, in which they will only run as fast and therefore as loud as needed to maintain a healthy air quality. As soon as pollution levels decrease after a spike, the speed and noise level will decrease accordingly.
Winner: BreatheSmart 45i
23 – 49 dB(A)
25 – 49 dB(A)
Sensors & Display
Laser sensors provide the BreatheSmart 45i and 75i with the current temperature, humidity, and amount of airborne particles inside the room. Changes are detected almost in real-time and can be used as input for the automatic mode (see above).
LED colour rings on the display of both devices make it easy to check the current air quality at a quick glance. The BreatheSmart 45i and 75i also allow you to view this information as well as the air quality history via an app on your smartphone (see below).
Winner: Draw
Yes / LED
Yes / LED
Connectivity & Compatibility
Aside from changing settings on the device itself, you can monitor and control both the BreatheSmart 45i and 75i remotely using a Wi-Fi connection and the Alen Air app on your smartphone. Unfortunately, neither model can be integrated with your smart voice assistant.
Winner: Draw
Yes
Yes
Weight & Dimensions
In the final round of this Alen BreatheSmart 45i vs 75i comparison, we will have a quick look at the weight and dimensions of the two devices. Unsurprisingly, the more powerful 75i is both the bigger and heavier model of the two.
Winner: BreatheSmart 45i
25 x 15 x 8.5 in, 15 lbs
27 x 18.5 x 11.5 in, 27 lbs
Conclusion: Alen BreatheSmart 45i vs 75i – Which is the Better Air Purifier?
Being the brand’s high-end device, it comes as to no surprise that the Alen BreatheSmart 75i had the upper hand in this comparison when it came to coverage area and CADR. Despite being so powerful, the 75i is also surprisingly quiet and energy-efficient.
That said, if the size of your room and level of air pollution allows it, you can safely go with the Alen BreatheSmart 45i instead. It comes with the same features such as automatic mode and Wi-Fi, is more portable due to its smaller size and weight, and obviously sells at a lower price.
Alen BreatheSmart 45i
Alen BreatheSmart 75i