Blueair Blue Signature moves more air (CADR) and covers a larger room than FreAire KN6391RGB.
Which purifier has higher CADR?
Blueair Blue Signature has published CADR; FreAire KN6391RGB does not.
Which purifier is quieter?
FreAire KN6391RGB is quieter (20 vs 23 dB).
Which purifier covers a larger room?
Blueair Blue Signature is recommended for about 705 sq ft based on CADR.
Which purifier has better smart features?
Blueair Blue Signature lists Wi-Fi or app control; FreAire KN6391RGB does not.
Which purifier has longer filter life?
Blueair Blue Signature lists a replacement interval of 179.99; FreAire KN6391RGB does not.
Bottom line
Blueair Blue Signature moves more air (CADR) and covers a larger room than FreAire KN6391RGB.
| Metric | Blueair Blue Signature | FreAire KN6391RGB |
|---|---|---|
| CADR (smoke) | 455 CFM | — |
| Recommended room size | 705 sq ft | — |
| Claimed coverage | 3385 sq ft | 1086 sq ft |
| Noise | 23 dB | 20 dB |
| Filter type | HEPASilent | HEPA |
| Filter interval | 179.99 | — |
| Smart features | None | None |