- CADR
- 125 (smoke, dust, pollen)
- Room Coverage
- 237 sq ft in 12.5 min, up to 1,138 sq ft in 1 hr
- Noise Level
- 19 dB on low, up to 48 dB on high
- Filtration
- HEPASilent: washable pre-filter + particle/carbon filter
- Filter Life & Cost
- 6-9 months, $29.99 replacement
- Dimensions
- 14.5 x 9.3 x 9.3 in, 4.9 lb
- Smart Features
- Blueair app, Wi-Fi, Alexa, Welcome Home geofencing, Clean Air ETA
Blueair
Blueair Blue Pure 511i Max
A small, whisper-quiet smart purifier built for bedrooms and nurseries.
All prices
| Store | Price | Checked | |
|---|---|---|---|
| Target Best price | $118.99 | AUG 17 | Go to store |
| Blueair | $139.99 | AUG 17 | Go to store |
Prices were checked on the dates shown and can change at any time. The store page is always authoritative. Shipping and taxes are not included.
Our verdict
Where it wins
- Among the quietest purifiers available at 19 dB on the low setting
- Lightweight and small enough for a nightstand
- Stable app connection with useful geofencing and scheduling
- Energy-efficient motor draws around 20W
Where it loses
- Weaker at odor and VOC removal than carbon-heavy designs
- Filter replacement cost adds up over a year of regular use
- Marketed coverage numbers assume shorter, faster air-change cycles
The 511i Max is built specifically for quiet bedroom use, and it is genuinely one of the quietest purifiers available at its lowest setting. It is not the pick for tackling cooking odors or a large room, but for a bedroom it is close to ideal.
Common questions
How quiet is the Blue Pure 511i Max on its lowest setting?
Blueair rates it at 19 dB on low, quieter than a whisper, rising to about 48 dB on the highest fan speed.
What room size is it designed for?
Blueair markets it for small to medium rooms, with coverage claims up to 1,138 sq ft in an hour at full speed.
Does the app require a subscription?
No, the Blueair app is free and adds scheduling, air quality monitoring, and geofencing on top of manual controls.
Prices last verified Aug 17, 2026.