Choose Blueair Blue Signature Small for higher CADR and larger-room coverage and Wi-Fi or app control. Choose Blueair Blue Pure 511 if you want lower noise.
Which purifier has higher CADR?
The Blueair Blue Signature Small has a smoke CADR of 160 CFM versus 123 CFM for the Blueair Blue Pure 511, a difference of 30%.
Which purifier is quieter?
Blueair Blue Pure 511 is quieter (24 vs 50 dB).
Which purifier covers a larger room?
Blueair Blue Signature Small fits a larger room (about 248 vs 191 sq ft recommended from CADR).
Which purifier has better smart features?
Blueair Blue Signature Small lists Wi-Fi or app control; Blueair Blue Pure 511 does not.
Which purifier has better filtration?
Both list HEPASilent filtration.
Bottom line
Choose Blueair Blue Signature Small for higher CADR and larger-room coverage and Wi-Fi or app control. Choose Blueair Blue Pure 511 if you want lower noise.
| Metric | Blueair Blue Signature Small | Blueair Blue Pure 511 | Difference / Winner |
|---|---|---|---|
| Smoke CADR | 160 CFM | 123 CFM | Blueair Blue Signature Small (+30%) |
| Recommended room size | 248 sq ft | 191 sq ft | Blueair Blue Signature Small (+30%) |
| Manufacturer claimed coverage | 248 sq ft | 189 sq ft | — |
| Minimum noise | 50 dB | 24 dB | Blueair Blue Pure 511 |
| Filter type | HEPASilent | HEPASilent | — |
| Replacement interval | — | 6 months | — |
| Power | 20 W | 16 W | — |
| Wi-Fi / app | Yes | No | — |
| Weight | 5.64 lb | 4.2 lb | — |