Product Review · Air Purifiers · #6 Ranked
Blueair 511i Max
Air purifiers — small-room smart HEPASilent · Reviewed by Katie · amazon.com live, Sept 28 2026
Why it scored a 81
At $139.00 the Blueair 511i Max is a small-room smart purifier from Consumer Reports' top-rated air-purifier brand for 2025. Value leads at 85 and Reliability at 89: it is the quietest unit here at 19 dB on low, weighs 4.2 lb, and adds Wi-Fi, auto mode and a PM2.5 readout at a manual-control price. Quality sits at 75 because HEPASilent pairs electrostatic charging with lower-grade media rather than true HEPA, and the small carbon load is weak on odors; the 1-year base warranty (3 registered) holds Warranty at 78. It is for a bedroom or office where silence and app control matter more than cooking smells.
What you're getting
- CADR 174 pollen / 159 dust / 153 smoke CFM
- 237 sq ft recommended room; cleans 569 sq ft in 30 min
- 19 dB on low to 48 dB on high, the quietest here
- Particle & Carbon filter $44.99, up to every 9 months (~$60/yr)
- Washable fabric pre-filter, available in colors
- 17 W; 4.2 lb; 14.5 x 9.3 x 9.3 in
- Wi-Fi + Blueair app: auto mode, night mode, PM2.5 readout, Alexa/Google
- HEPASilent (electrostatic + media, not true HEPA); 1-yr warranty, 3 registered
ViperScore breakdown
At a glance
- CADR 174 pollen / 159 dust / 153 smoke CFM
- 19 dB low to 48 dB high; 17 W, 4.2 lb
- 237 sq ft room; $44.99 filter up to every 9 months
- Price$139.00
- TierAir purifiers — small-room smart HEPASilent
- Category rank#6 of 10
Should you buy the Blueair 511i Max?
The Blueair 511i Max is the small-room purifier for a bedroom or home office where you want silence and phone control for under $100. At 19 dB on low it is the quietest unit we rank, it weighs 4.2 lb, and the Blueair app gives you auto mode and a PM2.5 readout that the similarly priced Levoit Core 300 lacks. It ranks sixth of ten. It comes from the brand Consumer Reports rated highest for air purifiers in 2025. If you need to cover more than about 240 sq ft, step up to the 311i Max.
Where it earns its score
- Quietest here. 19 dB on low and 48 dB on high, so you will not notice it running next to the bed.
- Smart for the money. Wi-Fi, the Blueair app, auto mode, night mode, a PM2.5 readout and Alexa or Google control at $139.00.
- Cheap to run. 17 W at maximum and a $44.99 Particle and Carbon filter that lasts up to 9 months, about $60 a year.
- Easy to live with. 4.2 lb, a washable fabric pre-filter that comes in colors, and a 14.5 in tall body that fits on a dresser.
What to know first
- Small-room only. CADR of 174 pollen / 159 dust / 153 smoke CFM, rated for a 237 sq ft room. Features is its lowest ViperScore factor because the sensor and modes are basic.
- Not true HEPA. HEPASilent uses electrostatic charging plus a media filter, with a low-ozone ionizer, which some buyers want to avoid.
- Register for the warranty. One year standard, three years if you register.
- Fabric pre-filter needs cleaning. It catches dust well, which means it needs a rinse or vacuum regularly.
Our verdict
The Blueair 511i Max scores 81, a Good Buy, and at $139.00 it is the smart small-room pick. Choose it over the Levoit Core 300 if you want auto mode, an app and the lowest noise floor. Choose the Core 300 if you want true HEPA with no ionizer and would rather spend $15 less.
Levoit Core 300
Questions buyers ask
How quiet is the Blueair 511i Max?
About 19 dB on the lowest setting and 48 dB on high, which makes it the quietest purifier in our rankings.
What size room is the Blueair 511i Max for?
Blueair recommends a 237 sq ft room, and says it cleans 569 sq ft in 30 minutes at a lower air-change rate.
Does the Blueair 511i Max work with Alexa?
Yes. It connects over Wi-Fi to the Blueair app and supports both Alexa and Google Assistant.
Ready to check it out?
Blueair 511i Max · ViperScore 81 · Good Buy · $139.00
How the other 9 air purifiers scored
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