Choose Blueair Blue Pure 211+ for higher CADR and larger-room coverage and lower noise. Choose Blueair Blue Signature SP3i if you want Wi-Fi or app control.
Which purifier has higher CADR?
The Blueair Blue Pure 211+ has a smoke CADR of 350 CFM versus 321 CFM for the Blueair Blue Signature SP3i, a difference of 9%.
Which purifier is quieter?
Blueair Blue Pure 211+ is quieter (31 vs 54 dB).
Which purifier covers a larger room?
Blueair Blue Pure 211+ fits a larger room (about 543 vs 498 sq ft recommended from CADR).
Which purifier has better smart features?
Blueair Blue Signature SP3i lists Wi-Fi or app control; Blueair Blue Pure 211+ does not.
Which purifier has better filtration?
Both list HEPASilent filtration.
Bottom line
Choose Blueair Blue Pure 211+ for higher CADR and larger-room coverage and lower noise. Choose Blueair Blue Signature SP3i if you want Wi-Fi or app control.
| Metric | Blueair Blue Pure 211+ | Blueair Blue Signature SP3i | Difference / Winner |
|---|---|---|---|
| Smoke CADR | 350 CFM | 321 CFM | Blueair Blue Pure 211+ (+9%) |
| Recommended room size | 543 sq ft | 498 sq ft | Blueair Blue Pure 211+ (+9%) |
| Manufacturer claimed coverage | — | 2250 sq ft | — |
| Minimum noise | 31 dB | 54 dB | Blueair Blue Pure 211+ |
| Filter type | HEPASilent | HEPASilent | — |
| Power | — | 36 W | — |
| Wi-Fi / app | No | Yes | — |
| Weight | — | 9.5 lb | — |