BreatheSmart 35i

$269
BreatheSmart 35i
$269
$269

BreatheSmart 35i

$269.00
HSA|FSA Eligible

Purifies air up to 1,000 sq ft every hour or 500 sq ft every thirty minutes.

  • Alen BreatheSmart 35i Dimensions
  • Alen BreatheSmart 35i
  • Alen BreatheSmart 35i
  • Alen BreatheSmart 35i Air Purifier | Preview
  • Alen BreatheSmart 35i Air Purifier | Preview
  • Alen BreatheSmart 35i Air Purifier | Preview
  • Alen BreatheSmart 35i Air Purifier | Preview
  • Alen BreatheSmart 35i Air Purifier | Preview
  • Alen BreatheSmart 35i Air Purifier | Preview
1 13

BreatheSmart 35i

BreatheSmart 35i

$269.00
$269.00
Sale Sold out HSA|FSA Eligible ? *One-time purchase only

Purifies air up to 1,000 sq ft every hour or 500 sq ft every thirty minutes.

1 -Select Filter Not sure? Take our quiz

Filter: Medical-grade H13 HEPA Air Filter

Good For: Capturing allergens, dust and mold (B3-Pure)

2 - Filter Subscription

How subscriptions work? How subscriptions work
Filters are automatically delivered on your schedule. No obligation, modify or cancel your subscription anytime.

Filter Subscription

$48.60 $54.00

Save 10%

Next payment on:

11-25-2025

Delivery every:

Just the one included filter

Purifier includes filter rated for:

6 - 12 months (varies by filter type/use)

The Alen BreatheSmart 35i delivers powerful air purification for small to medium spaces, combining advanced features with a compact, affordable design. Here’s why it stands out:

Advanced Filtration: Choose between Fresh or Pure filters with True HEPA efficiency to capture 99.9% of particles as small as 0.1 microns, perfect for tackling dust, allergens, and other pollutants.
Optimized for Medium Spaces: Designed to purify rooms up to 1,000 sq. ft. once per hour, or 500 sq. ft. every 30 minutes, making it ideal for apartments, bedrooms, and home offices.
Ultra-Quiet Performance: With a sound range of only 29-42 dB, the 35i is Alen’s quietest purifier, ensuring non-disruptive, whisper-quiet operation even at the highest speed.
Smart Sensor Technology: Equipped to monitor PM2.5, VOCs, CO2, temperature, and humidity, and with air quality alerts through the Alen Air app, you’re always in control of your indoor air.
App Control: The Alen Air app offers remote control, scheduling, and filter status updates, while Auto Light Mode dims panel lights in low-light environments.
Built to Last: Backed by Alen’s Forever Guarantee with regular filter replacement, this purifier offers reliable performance and lifetime peace of mind.

View full details

The Alen BreatheSmart 35i delivers powerful air purification for small to medium spaces, combining advanced features with a compact, affordable design. Here’s why it stands out:

Advanced Filtration: Choose between Fresh or Pure filters with True HEPA efficiency to capture 99.9% of particles as small as 0.1 microns, perfect for tackling dust, allergens, and other pollutants.

Optimized for Medium Spaces: Designed to purify rooms up to 1,000 sq. ft. once per hour, or 500 sq. ft. every 30 minutes, making it ideal for apartments, bedrooms, and home offices.

Ultra-Quiet Performance: With a sound range of only 29-42 dB, the 35i is Alen’s quietest purifier, ensuring non-disruptive, whisper-quiet operation even at the highest speed.

Smart Sensor Technology: Equipped to monitor PM2.5, VOCs, CO2, temperature, and humidity, and with air quality alerts through the Alen Air app, you’re always in control of your indoor air.

App Control: The Alen Air app offers remote control, scheduling, and filter status updates, while Auto Light Mode dims panel lights in low-light environments.

Built to Last: Backed by Alen’s Forever Guarantee with regular filter replacement, this purifier offers reliable performance and lifetime peace of mind.

CADR i Clean Air Delivery Rate

190

CFM i Cubic Feet per Minute

Speed 1: 66 CFM|Speed 2: 98 CFM| Speed 3: 135 CFM| Turbo: 190 CFM

Coverage

Purifies up to 1,000 sq ft every hour or 500 sq ft every thirty minutes

Dimensions

H 20.6" (52.32 cm) W 13" (33.02 cm) D 7.6" (19.30 cm)

Energy star i Products/Homes/Buildings that earn the ENERGY STAR prevent greenhouse gas emissions by meeting strict energy efficiency guidelines set by the U.S. Environmental Protection Agency and the U.S. Department of Energy

Yes

Filter cost

$54 | Using "Pure" Air Filter

Filter life max

Pure: 9-12 months
Fresh 6-8 months

Filtration rate

Captures 99.9% of airborne particles as small as 0.1 micron.

Noise level

Lowest Speed - 29 dB | Highest Speed - 42 dB

Ozone

0 PPM

Power consumption

0.9 to 40 watts

Power supply

24V, External Power Supply

Sensor

Automatic speed adjustment and coordinated to 5 color rings/ 4 speeds

Sound type

Pink Noise | All speeds

Speed settings

4

Warranty

Forever Guarantee | with Product Registration & Active Air Filter Subscription

Weight

13 lbs (5.8kg)

  • BreatheSmart 35i air purifier 
  • 35i True HEPA air filter
  • Quick start guide
  • User manual
  • Power adapter

FAST, Free Shipping. Alen offers free FedEx ground shipping within the Continental US. Additional shipping costs apply to Alaska, Hawaii, and Puerto Rico. For available options, add items to your cart and enter shipping details. Continental US orders typically arrive in 2-5 business days, while shipments to other locations may take 7-10 business days. Shipping times may be longer during peak seasons. Learn more.

60 Days to Love It or Return It. Try our Alen Air Purifiers and see for yourself why our customers are raving about them! And the best part, we offer a 60 Days Love It, or Return It guarantee. We are so confident you are going to love our air purifiers, we'll give you 60 days to try them out! Learn more. 

Alen offers the industry's first and only Forever Guarantee to ensure your purifier provides Pure Air for Life. To maintain this guarantee, customers must register the product and either subscribe to an air filter replacement plan or provide proof of annual filter purchases. If an issue arises and can't be resolved by troubleshooting, Alen will replace the unit free of charge​​​. Learn more.

What is the Alen filter capturing?

Select filter below:

Pure

HEPA

Capturing allergens, dust, and mold (B3-Pure)

We capture 99% of:

  • Dust Dust
  • Pet Dander Pet Dander
  • Pollen Pollen
  • Hair Hair

Perfect for:

  • Allergy Relief
  • Pet Owners
  • Airborne Particles
  • Capturing Mold Spores
Still unsure? Take our quiz

Fresh

HEPA + Carbon

Absorbing wildfire smoke and secondhand smoke, harmful chemicals and VOCs, cooking and common household odors + capturing allergens, dust, and mold (B3-Fresh)

Everything that Pure captures, plus:

  • VOC VOC
  • Cooking Odor Cooking Odor
  • Pet Odor Pet Odor
  • Diaper Odor Diaper Odor
  • Cigar Smoke Cigar Smoke

Perfect for:

  • Airborne Particles
  • Capturing chemicals from vaping and smoking
Still unsure? Take our quiz

PERFECT FOR MEDIUM ROOMS UP TO 1,400 SQ FT

BreatheSmart FLEX Coverage

Designed for bedrooms, offices, and other medium-sized spaces, the Alen FLEX efficiently purifies 700 sq ft - 1,400 every 60 minutes on high speed. Its compact size, quiet performance, and customizable panels make it a seamless addition to any room.

Perfect for medium/small rooms up to 1,600 sq ft

BreatheSmart 45i Coverage

Perfect for purifying large spaces including living rooms, kitchens and master bedrooms up to 1,600 sq ft. This powerful yet whisper-quiet air purifier ensures every corner of your room is filled with clean, fresh air.

Perfect for large rooms up to 2,800 sq ft

BreatheSmart 75i Coverage

Perfect for purifying large spaces including living rooms, kitchens and master bedrooms up to 2,800 sq ft. This powerful yet whisper-quiet air purifier ensures every corner of your room is filled with clean, fresh air.

Perfect for medium/small rooms up to 1,000 sq ft

BreatheSmart 35i Coverage

Perfect for purifying small spaces up to 1,000 sq ft @ one hour and 500 sq ft every 30 minutes. Power-packed BreatheSmart 35i: our most compact, most affordable smart purifier yet.

Compare vs Other Models

Currently Viewing

BreatheSmart FLEX

BreatheSmart FLEX

Coverage: 700 to 1,400 sq ft

Currently Viewing

BreatheSmart 45i

BreatheSmart 45i

Coverage: 800 to 1,600 sq ft

Currently Viewing

BreatheSmart 75i

BreatheSmart 75i

Coverage: 1,400 to 2,800 sq ft

Currently Viewing

BreatheSmart 35i

BreatheSmart 35i

Coverage: 500 to 1,000 sq ft

Compare models

Not sure which model is right for you?Take the quiz
BreatheSmart 75i

BreatheSmart 75i

Ideal for large living rooms and open-concept spaces
Coverage
1,400 to 2,800 sq ft
App Controlled
Yes
Compatible filter types

Pure - best for allergens
Fresh - best for smoke & harmful chemicals
Odor - best for neutralizing household odors

What’s Included?
  • BreatheSmart 75i air purifier
  • HEPA filter (options with carbon also available)
  • White panel (designer panels available for purchase)
  • Quick start guide
From $799
View Product
BreatheSmart 45i

BreatheSmart 45i

Standard living rooms and large master bedrooms
Coverage
800 to 1,600 sq ft
App Controlled
Yes
Compatible filter types

Pure - best for allergens
Fresh - best for wildfire smoke & harmful chemicals
Odor - best for neutralizing odors
VOC/Smoke filter - best for gasses from smoke & harmful chemicals

What’s Included?
  • BreatheSmart 45i air purifier
  • HEPA filter (options with carbon also available)
  • White panel (designer panels available for purchase)
  • Quick start guide
From $429
View Product
BreatheSmart FLEX

BreatheSmart FLEX

Children’s bedrooms, home offices, FLEXible spaces
Coverage
700 to 1,400 sq ft
App Controlled
No
Compatible filter types

Pure - best for allergens
Fresh - best for wildfire smoke & harmful chemicals
Odor - best for neutralizing odors
VOC/Smoke filter - best for gasses from smoke & harmful chemicals

What’s Included?
  • BreatheSmart FLEX air purifier
  • HEPA filter (options with carbon also available)
  • White panel (designer panels available for purchase)
  • Quick start guide
From: $299.00 $349.00
View Product
BreatheSmart 35i

BreatheSmart 35i

Big power for small spaces, at the best value.
Coverage
500 to 1,000 sq ft
App Controlled
Yes
Compatible filter types

Pure - best for allergens
Fresh - best for smoke & harmful chemicals

What’s Included?
  • BreatheSmart 35i air purifier
  • 35i HEPA air filter
  • Quick start guide
From $269
View Product
T500

T500

Compact, Powerful Air Cleaning for Any Room
Coverage
Up to 500 sq ft coverage at a one hour air exchange*
App Controlled
No
Compatible filter types

Pure - best for allergens

What’s Included?
  • T500 air purifier
  • True HEPA-Pure air filter
  • Quick start guide
  • Owner's Manual
From: $149.00 $199.00
View Product

Stay Connected With Your Alen App

Smart Connect Alen App

Detailed Control: Adjust settings across multiple devices and create schedules that match your routine.

Smart Sensors: Track PM 2.5, TVOC, eCO2, temperature, and humidity levels in your air, and track this data in the Alen Air App.

More Air Insights: Get personalized tips based on what your Alen purifier detects with airID.

SMART RFID Filters: Keep track of remaining filter life, even when you swap filters. The Alen Air app will notify you when it's time for a filter replacement.

Over-the-Air (OTA) firmware updates: As Alen launches ongoing enhancements, you will be able to update your purifier via the Alen Air app.

Available on:

FAQs

How many fan speeds does the 35i have?

The BreatheSmart 35i comes with four fan speeds, ranging from a whisper-quiet low setting at 29 dB to a higher power setting that still remains under 45 dB, ensuring customizable comfort without disrupting your space.

How does the BreatheSmart 35i smart filter system work?

The 35i uses RFID smart filters that communicate with the purifier, tracking filter life and letting you know when it’s time for a replacement. The app also allows you to monitor filter status.

Does the BreatheSmart 35i support firmware updates?

Yes, the BreatheSmart 35i supports over-the-air firmware updates via the Alen Air app, ensuring you always have the latest features and improvements without needing to buy a new unit.

What happens if my BreathSmart 35i stops working after the warranty expires?

The BreatheSmart 35i is covered by Alen’s Forever Guarantee as long as you have a filter subscription. Even after years of use, if anything goes wrong, we will repair or replace the unit for free.

How does the BreatheSmart 35i compare to other Alen Air Purifer models?

The BreatheSmart 35i is the most compact and affordable model in the smart purifier lineup. It offers advanced filtration with a quiet motor, smart sensors, and app control—making it perfect for smaller spaces like apartments.

What are the benefits of upgrading to the 35i if I already own another air purifier?

The BreatheSmart 35i offers modern upgrades like quieter operation (29-45 dB), better smart features (AQI monitoring), and the ability to control multiple units through the app. With an active filter subscription, it is also covered by a Forever Guarantee, so it’s a long-term investment.

Is the BreatheSmart 35i energy efficient?

Yes, the 35i uses only 40 watts at maximum power, making it an energy-efficient option for continuous use, even on higher settings

How often do I need to change the filters for BreatheSmart 35i?

Depending on usage, we recommend changing the filter every 6-9 months. The 35i comes with smart sensors that monitor air quality and will alert you through the app when it’s time to replace the filter.

What is the Alen Forever Guarantee?

The Alen Forever Guarantee means your BreatheSmart 35i is covered for life. As long as you subscribe to regular filter replacements, if any issue arises, we’ll repair or replace it for free. Learn more.

Can I control multiple 35i units via the Alen Air app?

Yes, you can control several 35i units through the Alen Air app, allowing you to manage air quality in multiple rooms, track filter life, and set schedules for each unit from a single interface.

How does the Auto Light Mode work for the BreatheSmart35i?

The 35i features an Auto Light Mode that dims the control panel lights in a dark room, automatically adjusting to the ambient light to provide a distraction-free experience at night.

What is the AQI feature on the BreatheSmart 35i?

The BreatheSmart 35i monitors air quality using a built-in Air Quality Index (AQI) sensor. It provides real-time data on PM2.5 levels and VOCs through the Alen Air app, helping you ensure the air in your home stays clean.

What are the dimensions of the BreatheSmart 35i?

The BreatheSmart 35i is designed to be compact yet powerful, measuring 13 inches in width, 7.6 inches in depth, and 20.3 inches in height. It fits perfectly in small spaces like apartments or bedrooms.

How does the BreatheSmart 35i compare to other Alen models in terms of price and features?

The 35i is the most affordable smart purifier in the lineup. Despite the lower price, it includes key features such as smart sensors, app control, and a quiet motor, making it a great value for smaller rooms.

What makes Alen different from other air purifier brands?

Alen is committed to empowering users with control over their indoor air quality. We offer personalized air solutions through advanced filtration, smart features, and an industry only Forever Guarantee to back our high-quality products.

How does the BreatheSmart 35i handle common indoor pollutants like pet dander, smoke, and VOCs?

The 35i has HEPA-grade filtration that captures 99.9% of particles down to 0.1 microns, including pet dander, smoke, and VOCs. It’s especially effective for pet owners and people living in wildfire-prone areas.

Why should I trust Alen’s products and claims?

Alen is committed to transparency and quality. All our products undergo rigorous testing, and we back them with a Forever Guarantee. We also provide scientifically-backed insights about indoor air quality to guide your decisions.

How do I know if the BreatheSmart 35i is the right purifier for my needs?

The 35i is ideal for small to medium spaces, like bedrooms and offices, up to 1,000 sq. ft. It has advanced smart features like real-time AQI monitoring and app control, making it a great choice for allergy sufferers and those with pets.

How large of a room can the BreatheSmart 35i purify?

The BreatheSmart 35i is perfect for spaces up to 1,000 sq ft with one full air cycle per hour or 500 sq. ft. with two cycles. It’s ideal for small apartments, offices, or bedrooms.

What features does the Alen Air app provide?

The Alen Air app allows you to monitor air quality in real time, control multiple devices, set schedules, and receive air quality alerts for PM2.5, humidity, and more. You can also track your filter’s lifespan.

What does the Auto Light Mode do for the BreatheSmart 35i do?

Auto Light Mode automatically adjusts the brightness of the control panel based on ambient lighting, dimming in dark rooms for an undisturbed night’s sleep.

Can the BreatheSmart 35i help with wildfire smoke and VOCs?

Yes, the 35i includes advanced filtration options that can capture particles from smoke, VOCs, and odors, making it a perfect option for areas affected by wildfires or cooking-related air quality issues.

Is an air purifier worth the ongoing costs of filters and electricity?

The BreatheSmart 35i is energy efficient, using just 40 watts even at its highest setting, and the long-lasting filters only need to be replaced every 6-9 months. Our subscription service helps manage these costs by including 10% off filter replacements, giving you cleaner air without hassle.

Is the BreatheSmart 35i effective for allergies or asthma?

Yes, the BreatheSmart 35i is equipped with HEPA filtration options that can target allergens like dust, pollen, and pet dander, helping to reduce asthma and allergy symptoms. The 35i also captures VOCs for a cleaner home.

How quiet is the 35i during operation?

The BreatheSmart 35i is our quietest purifier, operating between 29 and 45 dB, which is softer than typical conversation or background noise, ensuring peaceful operation even on the highest fan speed.

On the blog

What Does Utopiair Mean?

What Does Utopiair Mean?

What Does Utopiair Mean?

clock 5 minute read
The Austin Business Journal Recognizes Alen as One of the Best Places to Work

The Austin Business Journal Recognizes Alen as ...

The Austin Business Journal Recognizes Alen as One of the Best Places to...

clock 3 minute read
Warburg Lee Becomes Alen’s New CEO To Lead Company’s Clean Air Revolution

Warburg Lee Becomes Alen’s New CEO To Lead Comp...

Warburg Lee Becomes Alen’s New CEO To Lead Company’s Clean Air Revolution

clock 3 minute read
Consumer Reports Ranks Alen #1 For the Second Year in a Row

Consumer Reports Ranks Alen #1 For the Second Y...

Consumer Reports Ranks Alen #1 For the Second Year in a Row

clock 4 minute read
Reviews
Q&A
Reviews
Q&A