Alen BreatheSmart Air Purifiers: Which Size Fits Your Room?
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The short answer: The BreatheSmart 45i is the best all-round pick for most large rooms, at $449 and rated 4.8. Choose the 35i if you're purifying a bedroom and want to spend $160 less, or the 75i if you need a whole-floor unit and the $799 price and 4.9 rating justify the $350 step up.
- Best overall: BreatheSmart 45i — A mid-tier $449 unit rated 4.8, it sits $160 above the smallest model and $350 below the largest, making it the balanced choice for a large room. See price at alen.com
- Best value: BreatheSmart 35i — At $289 it's the least expensive of the three and still rated 4.8, so it suits a bedroom without the larger units' cost. See price at alen.com
- Best premium: BreatheSmart 75i — The $799 75i carries the highest rating here at 4.9 and is built for whole-floor coverage, $510 above the 35i. See price at alen.com
What changed: All three models are holding at their 90-day lows, with prices flat across the past 90 days.
| Product | Price now | 90-day low | Rating | |
|---|---|---|---|---|
| BreatheSmart 35i | $289.00 | $289.00 | 4.8 | alen.com |
| BreatheSmart 45i | $449.00 | $449.00 | 4.8 | alen.com |
| BreatheSmart 75i | $799.00 | $799.00 | 4.9 | alen.com |
BreatheSmart 35i
Pros
- 4.8 rating
- $289.00 current price, the lowest in the BreatheSmart lineup
- $160.00 less than the BreatheSmart 45i and $510.00 less than the BreatheSmart 75i
- Price has held flat at its 90-day low of $289.00
Cons
- Smallest and least expensive model in the family, so it suits smaller spaces than the 45i or 75i
Who it's for: Anyone who wants an Alen BreatheSmart purifier at the lineup's lowest price and doesn't need the larger-room coverage of the 45i or 75i.
BreatheSmart 45i
Pros
- Rated 4.8 out of 5
- Priced at $449.00, its 90-day low, with a flat price trend
- Costs $160.00 more than the BreatheSmart 35i and $350.00 less than the BreatheSmart 75i, sitting in the middle of the lineup
Cons
- At $449.00 it is the middle price of the three, above the $289.00 BreatheSmart 35i
Who it's for: Someone who wants a mid-lineup Alen BreatheSmart purifier between the smaller 35i and the larger 75i.
BreatheSmart 75i
Pros
- Highest rating in the lineup at 4.9
- Priced at its 90-day low of $799.00 with a flat trend
- The largest-room option in the family, suited to whole-floor coverage
Cons
- Costs $350.00 more than the BreatheSmart 45i
- Costs $510.00 more than the BreatheSmart 35i
Who it's for: Buyers who need to purify a whole floor and want the top-rated model in the family, with the budget for a $799.00 unit.
How we chose
We compared the three BreatheSmart models on current price, 90-day price behavior and rating, then matched each to a room size from bedroom to whole floor.
All three held a flat price over the past 90 days, each sitting at its 90-day low. The BreatheSmart 35i is $289.00 and rated 4.8. The BreatheSmart 45i is $449.00 and rated 4.8. The BreatheSmart 75i is $799.00 and rated 4.9.
On price, the 45i costs $160.00 more than the 35i, and the 75i costs $350.00 more than the 45i, or $510.00 more than the 35i. The 35i and 45i share a 4.8 rating, while the 75i carries the highest rating of the three at 4.9.
We matched each unit to a room size: the 35i for a bedroom, the 45i for a large room, and the 75i for a whole floor. That sizing, alongside the steady pricing and the ratings above, is what led us to the 45i as the best all-round pick for most large rooms.
Who should skip these
If you're purifying one small room, this lineup is more than you need. The least expensive unit here, the BreatheSmart 35i, is $289.00, and the next step up, the BreatheSmart 45i, is $160.00 more at $449.00. A whole-floor unit, the BreatheSmart 75i, is $799.00 — $510.00 more than the 35i and $350.00 more than the 45i. For a single small space, those are larger commitments than the job calls for.
All three are priced at their 90-day low and have held flat over that window, so there's no cheaper moment to wait for within this family. If your room is small, or your budget sits well below $289.00, look at a different lineup rather than stretching to the entry point here.
The same goes if you want a size or set of features outside what these three cover. We're recommending the 45i for most large rooms at $449.00, the 35i for a bedroom at $289.00, and the 75i for a whole floor at $799.00 — all rated 4.8 or 4.9. If none of those three fits your space, this isn't the family to shop.
How to choose the right one
Start with the room, not the price. The BreatheSmart 35i is the bedroom unit at $289.00, rated 4.8, and it sits at its 90-day low. If a single bedroom is what you're purifying, this is where we'd put the money, and it's $160.00 less than the 45i.
The BreatheSmart 45i is the large-room pick at $449.00, also rated 4.8 and also at its 90-day low. The step up from the 35i is $160.00, and that's the decision most people are actually making: bedroom coverage versus large-room coverage.
For a whole floor, the BreatheSmart 75i is $799.00, rated 4.9, at its 90-day low. It's $350.00 more than the 45i and $510.00 more than the 35i. We'd only take that step when the space genuinely spans a floor, because the 45i already covers the large-room case at $350.00 less.
Each of the three has held the same price across its 90-day range, so there's no timing angle to work here — the choice is coverage against the price step.
Questions readers ask
Which Alen BreatheSmart model should I pick for a bedroom versus a whole floor?
The lineup runs from the BreatheSmart 35i at $289.00 up to the BreatheSmart 75i at $799.00, with the 45i in between at $449.00, so you can match the unit to the room size you need to cover.
How much more does each step up cost?
The BreatheSmart 45i costs $160.00 more than the 35i, the 75i costs $350.00 more than the 45i, and the 75i costs $510.00 more than the 35i.
Have these prices changed recently?
All three models are flat over the last 90 days and each is currently at its 90-day low, with the 35i at $289.00, the 45i at $449.00 and the 75i at $799.00.
How are the models rated?
The BreatheSmart 35i and 45i are both rated 4.8, while the BreatheSmart 75i is rated 4.9.
Update history
- — All three models are holding at their 90-day lows, with prices flat across the past 90 days.
- — Prices and availability refreshed
- — First published
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