To achieve maximum performance we recommend placing your Blue Pure 211i Max in a room around 635 ft² room so your air purifier can clean the air at the AHAM recommendation of 4 times every 12.5 minutes. The Blue Pure 211i Max will clean a 1,500 ft² space in 30 minutes, and 3,000 ft² in 1 hour.

Operates quieter than a whisper on low at 23 db and is no louder than 53 dB on high fan speed.

Your filter will last up to 1 year thanks to our proprietary RealTrack algorithm that accurately calculates the remaining filter lifetime based on fan speed, usage time and pollution levels.

When it's time to replace the filter, the filter replacement LED on the interface will turn red to remind you. Alternatively, connect to the Blueair app to receive an alert and easily re-order at the touch of a button.

Register your product to extend the 1-year warranty to a 3-year warranty.

While many Blueair units come equipped with a PM2.5 sensor, some models, including Blue Pure 211i Max, Protect 70i, or Classic Pro CP7i, have advanced sensors that measure PM1, PM2.5, and PM10 levels for more precise air quality monitoring. However, the display on these models can only show one of these three particulate matter (PM) values at a time due to the size of the screen. The display can toggle between PM1, PM2.5, and PM10 readings to track the levels of different pollutants in their environment. Switching between these indicators does not affect the air purifier's performance or target a specific pollutant size to remove from the air. The air purifier continuously works to remove particles down to 0.1 micron from the air regardless of which PM indicator is displayed.