Our verdict
Pick the Blueair Blue Pure 411i+ Max if your room is larger and you want the lower price. Pick the Blueair Blue Pure 511i Max if it is the cheaper of the two on the day you buy.
The central trade-off
Rated room size. Blueair Blue Pure 411i+ Max: 259 sq ft; Blueair Blue Pure 511i Max: 237 sq ft.
Power draw. Blueair Blue Pure 511i Max states 20 watts; the other's maker page doesn't.
Filters. Blueair Blue Pure 411i+ Max: HEPASilent.
Filters. Blueair Blue Pure 511i Max: HEPASilent.
Price. When we checked, the Blueair Blue Pure 411i+ Max listed for less ($119 against $140); prices move, so check both buttons.
Side by side
| Specification | Blueair Blue Pure 411i+ Max | Blueair Blue Pure 511i Max |
|---|---|---|
| Rated room size | 259 sq ft | 237 sq ft |
| Smoke CADR | Not stated by the maker | Not stated by the maker |
| CADR | Not stated by the maker | Not stated by the maker |
| Quietest setting | Not stated by the maker | Not stated by the maker |
| Noise | Not stated by the maker | 48 dB |
| Power draw | Not stated by the maker | 20 watts |
| Filters | HEPASilent | HEPASilent |
| Warranty | 1 years | 1 years |
Values are the makers' published specifications. "Not stated" means the maker doesn't publish it.
Which should you choose?
Choose the Blueair Blue Pure 511i Max if
- It is the cheaper of the two on the day you buy