KNKA APH4000
#5 in Medium roomsFull review
A low-priced purifier for medium rooms up to about 350 sq ft. It has a sensor-driven auto mode, but filter costs add up if you follow KNKA’s replacement schedule.
Amazon $99.99$99.99
2 KNKA air purifiers ranked. Each one is scored and ranked against every brand in its room size, so "#3 mid-size" means third of all mid-size air purifiers here, not third among KNKA's own.
KNKA makes 2 current air purifiers: 1 small rooms and 1 medium rooms. Prices run from $89.99 for the KNKA APH2500P to $99.99 for the KNKA APH4000. Its best-rated model in each size: the KNKA APH2500P (#8 of 12 small rooms, rated 3.1) and the KNKA APH4000 (#5 of 7 medium rooms, rated 3.4). Models deliver 119 to 226 cfm of smoke CADR.
Prices were last checked October 22, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
KNKA air purifiers 2
- KNKA APH4000#5 medium roomsFull review
A low-priced purifier for medium rooms up to about 350 sq ft. It has a sensor-driven auto mode, but filter costs add up if you follow KNKA’s replacement schedule.
Amazon $99.99$99.99226350 sq ft$143.96/year- - KNKA APH2500P#8 small roomsFull review
A pet-oriented purifier for bedrooms up to about 185 sq ft. Its hair-catching pre-filter is the draw, but plain purifiers deliver more clean air per dollar.
Amazon $89.99$89.99119184 sq ft$119.96/year-
