Air purifier room matcher
Enter your room and what you're fighting. We'll work out the cleaning power you need and show which purifiers have it.
How we match
Required CADR = room volume (sq ft × ceiling height) × air changes per hour ÷ 60. We use 4 changes/hour for everyday use, 5 for allergies and pets, and 6 for smoke. We compare against the purifier's smoke CADR for smoke and everyday use, and the lower of its dust and pollen CADRs for allergies (Levoit publishes one combined figure, which we use for all three). CADR is measured on the highest fan speed; "quiet" sizing adds 50% headroom so the purifier can do the job on a medium setting. Yearly cost = filters replaced on the brand's schedule (6 months where not stated) + electricity running 24/7 at about 40% of max power, at $0.17/kWh.