Find the room size an air purifier can serve at the right air changes.
A purifier needs a clean-air delivery rate equal to the room volume times the desired air changes per hour. Comparing that to the CADR rating checks adequacy. An undersized purifier cleans too slowly to help with allergens or smoke, so matching CADR to room size is essential.
Air Purifier Coverage
Required CADR = room volume x air changes / 60
Required CADR = room volume x air changes / 60 A purifier needs a clean-air delivery rate equal to the room volume times the desired air changes per hour. Comparing that to the CADR rating checks adequacy.
An undersized purifier cleans too slowly to help with allergens or smoke, so matching CADR to room size is essential.
This calculator takes 4 inputs: Room area, Ceiling height, Air changes/hour, Purifier CADR. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.