Captures common airborne triggers
Medical-grade HEPA filtration captures 99.9% of particles measuring 0.1 micron or larger, including airborne pollen, household dust and pet dander that can contribute to allergy or asthma discomfort.
BreatheSmart 45i · Asthma & Allergy Friendly®
Cleaner air. A more comfortable home.
Quiet HEPA purification for pollen, dust and pet dander. Auto mode adjusts as the air changes.
Free 2-day shipping
60-day trial
Forever Guarantee
Three reasons to choose with confidenceClear value before you bring it home.
Flexible paymentHSA/FSA eligible
Qualifying one-time purchase through Flex.
Fine-particle filtration99.9% capture
Particles measuring 0.1 micron or larger.
Room-sized performance950 sq ft
Air refreshed every 30 minutes.
Everyday support for allergy and asthma concerns
Reduce more of the airborne triggers moving through your home.
For people living with allergies or asthma, airborne pollen, dust and pet dander can make a room less comfortable. The BreatheSmart 45i continuously draws in room air, captures fine particles in its medical-grade HEPA filter and automatically responds when particle levels rise.
Provides more cleaning when it is needed
The sensor monitors airborne particle levels. When cooking, cleaning, outdoor air or pets affect the room, Auto mode increases fan speed, then quiets down as conditions improve.
Supports a more comfortable indoor environment
Continuous filtration can reduce exposure to airborne irritants in bedrooms and living spaces. The five-color ring and Alen Air app make air quality, schedules and filter status easy to follow.
The BreatheSmart 45i is Asthma & Allergy Friendly® Certified. Air purification can reduce airborne particles but is not a medical treatment; individual comfort and health outcomes vary.
Made for confident ownership
The Alen Difference
A simple vertical comparison of the ownership details that matter over time.
What mattersOthers
Others01Lifetime warranty
Included
1 yearTypical comparison shown
02Scientifically studied
Included
FewLimited study support
03Customize your style
Six finishes
Limited optionsVaries by model
04Long filter life
9–12 months
6 monthsTypical comparison shown
05In-home trial
60 days
30 daysTypical comparison shown
Category comparison shown in Alen brand materials. Warranty, study, finish, filter-life and trial terms vary by product; verify current terms before purchasing.
The Alen difference
Compare the 45i with what other purifiers make you verify.
The strongest comparison is not a longer feature list. It is whether the purifier gives you proven capture, useful room coverage, certified quiet, automatic control and long-term protection in one system.
99.9%Captures particles 0.1 micron or larger as air moves through the filter.
AutoSenses changing air quality and adjusts fan speed without constant input.
24–50 dBAQuiet Mark Certified operation designed for bedrooms and shared spaces.
950 sq ftRefreshes the air every 30 minutes in the rooms where life happens.
| What matters |  BreatheSmart 45iVerified Alen product features | When comparing other purifiers |
|---|---|---|
| Fine-particle capture | Captures 99.9% of particles 0.1 micron or larger. | ?Check the tested particle size—not only whether “HEPA” appears on the box. |
| Useful room coverage | Refreshes 950 sq ft every 30 minutes, or 1,900 sq ft every hour. | ?Check the refresh time behind the advertised square-foot number. |
| Quiet performance | Quiet Mark Certified with a listed range of 24–50 dBA. | ?Look for the full low-to-high dBA range and independent quiet certification. |
| Automatic air care | Sensor, Auto mode, five-color ring, app controls and airID insights work together. | ?Confirm whether sensing, automatic response, visible feedback and remote controls are all included. |
| Independent reassurance | Asthma & Allergy Friendly®, Quiet Mark and ENERGY STAR certified. | ?Verify which performance claims are backed by named third-party certifications. |
| Long-term ownership | Forever Guarantee coverage with registration and genuine-filter requirements. | ?Compare warranty length, replacement terms and ongoing filter requirements. |
| Fits a finished home | Six finish options for bedrooms, living rooms and shared spaces. | ?Check whether the design and available finishes suit the room where it will run every day. |
45i features and certifications are based on Alen’s current product and home pages. Competing products vary; verify the current specifications, certifications and warranty terms of any model you are considering.
Independent reassurance
Certified for the things premium buyers should not have to guess about.
Trust is strongest when the proof is specific, visible and easy to verify.
Certified by the Asthma & Allergy Friendly® Certification Program.
Quiet Mark Certified for low-noise operation.
ENERGY STAR certified.
Recognized by Mom’s Choice.
Real stories and product guidance
What others are saying
Tap any portrait video to hear customer experiences and see practical guidance from Alen. Swipe horizontally on mobile to explore the full collection.
The video collection is available on the live BreatheSmart 45i product page.
Watch the videos4.9/5 from 1,877 reviews
What owners notice after the box is gone.
Quiet operation, less dust, simple setup and a design that fits the home appear again and again.
★★★★★
“Quiet and very efficient. It was shocking to see how much dust it collected.”
Published BreatheSmart 45i review★★★★★
“Easy to set up, and the appearance just blends in with my decor.”
Published BreatheSmart 45i review★★★★★
“It has helped my allergies so much. It is a pleasure to not have to blow my nose every two minutes.”
Published BreatheSmart 45i reviewOwnership, made straightforward
Easy to start. Easy to keep.
The day-to-day routine is simple, and the important replacement and protection details are clear before you buy.
Try it in your home
Free 2-day shipping gets it there quickly, and the 60-day trial gives you time to experience it in the room where it will run.
Let Auto mode manage the routine
The sensor, five-color ring and app controls keep air quality, schedules and filter status easy to follow.
Replace the filter and keep coverage active
Essential filters are listed for 9–12 months; Advanced and Ultimate for 6–8 months. Registration and genuine-filter requirements apply to the Forever Guarantee.
25%
Off
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Choose your 45i
Choose your finish and filter.
Select the look for your room, then match the included HEPA filter to your household. The price and Alen product link update with your exact configuration.
$336.75
$449.00
25% off
Shop selected configuration
White · Essential (Pure) · $336.75 after 25% checkout savings (regular $449.00)
Designed for real homes
Made to belong in the room.
A purifier can run every day without making the room feel technical. The 45i pairs a slim profile and quiet operation with finishes chosen to suit bedrooms, living spaces and guest-ready homes.
WhiteOakWeathered GrayBrushed StainlessGraphiteEspresso
Simple from day one: Set Auto mode and let the purifier respond, or use the Alen Air app for schedules, settings and filter-status updates.
One quiet, automatic system
Sense. Clean. Respond.
The 45i turns changing room air into a simple three-step routine, without asking you to constantly manage it.
01
Senses the room
The onboard sensor tracks changing particle levels and translates them into an easy-to-read color ring.
02
Cleans continuously
Room air moves through the filter, where fine airborne particles are captured before cleaner air returns to the space.
03
Responds automatically
Auto mode adjusts fan speed when more cleaning is needed, then settles back as air quality improves.
Need help choosing?
Match the filter to what you want removed from the air.
Every BreatheSmart 45i configuration uses medical-grade HEPA filtration. Essential focuses on particles; Advanced adds broader carbon support; Ultimate adds the most odor-focused carbon and catalyst support.
Your selected filter and finish are carried into the Alen product page.
Essential
(Pure)
Included with the base configuration
- Airborne dust and allergen concerns
- 99.9% capture of particles 0.1 micron or larger
- A clear starting point when odors are not the priority
Typical listed replacement: 9–12 monthsActual life depends on use and conditions.
Advanced
(Fresh)
Adds $15 to the regular configuration price
- Everything addressed by Essential
- Added carbon for smoke, chemicals and VOC concerns
- A balanced choice for kitchens, shared living spaces and common pollutants
Typical listed replacement: 6–8 monthsActual life depends on use and conditions.
Ultimate
(Odor)
Adds $30 to the regular configuration price
- Everything addressed by Advanced
- More carbon and catalyst support for odors, smoke and VOCs
- Designed for pet-filled homes and broader odor or mold concerns
Typical listed replacement: 6–8 monthsActual life depends on use and conditions.
Questions, answered
Easy to choose. Easy to live with.
Is the BreatheSmart 45i a good fit for allergies and asthma concerns?
The 45i is Asthma & Allergy Friendly® Certified. Its filters capture 99.9% of particles 0.1 micron or larger, including airborne dust and allergens. It is an air purifier—not a medical treatment—so health outcomes can vary.
How much space does it cover?
Alen states that the 45i purifies up to 1,900 sq ft every hour or 950 sq ft every 30 minutes, making it a fit for main suites, living areas and family rooms.
How quiet is it?
The product page lists 24 dB at the lowest fan speed and 50 dB at the highest. The BreatheSmart 45i is also Quiet Mark Certified.
Which filter should I choose?
Essential is the straightforward choice for dust and allergens. Advanced adds carbon for smoke, chemicals, VOCs and common pollutants. Ultimate adds a more powerful carbon and catalyst layer for broader odor, smoke, VOC, mold and pet-home concerns.
How often will I replace the filter?
Alen lists 9–12 months for Essential and 6–8 months for Advanced or Ultimate under recommended 24/7 operation. Actual life depends on use and conditions.
Can I use HSA or FSA funds for the BreatheSmart 45i?
Yes. Alen states that one-time purchases of its air purifiers and filters are HSA/FSA eligible through Flex at checkout. Subscriptions are not eligible. Eligibility and reimbursement rules can vary by plan, so confirm with your HSA/FSA administrator.
What does the Forever Guarantee require?
Register the purifier and use genuine Alen replacement filters according to Alen’s policy. Review the current Forever Guarantee terms on alen.com before purchase.
What comes in the box?
The product page lists the BreatheSmart 45i purifier, a 45i HEPA filter, designer panel when selected, quick-start guide, user manual and power adapter.
Can I control it from my phone?
Yes. The Alen Air app supports remote air-quality monitoring, settings, scheduling and filter-status updates.
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Give the rooms you love air that keeps up.
Choose the finish and filter that fit your home, with free 2-day shipping, a 60-day trial and long-term coverage through Alen’s Forever Guarantee terms.
Shop NowBreatheSmart 45i
25% off · $336.75$449.00 · shown at checkout
25% off · $336.75