Air Quality

2 guides · prices re-checked weekly

Before you buy

Air purifier marketing runs on room-size claims that assume ideal conditions. The number that matters is CADR, the clean air delivery rate, set against the actual volume of your room, and the honest rule of thumb is to size up rather than down.

A unit rated exactly for your room will only hit that figure on its loudest setting, which is the setting nobody uses at night.

For particulates, smoke, pollen and pet dander, a true HEPA filter is the requirement, and anything advertising HEPA-“type” or HEPA-“like” is not the same thing. Odors and volatile compounds need activated carbon, which is a separate filter with a shorter life. Work out the annual filter cost before you buy. An inexpensive purifier with expensive proprietary filters usually costs more over three years than the reverse.

Our air quality guides compile manufacturer specifications, testing published by others and verified buyer reviews, with attention to measured noise levels and real filter pricing. A purifier manages symptoms. It does not fix dampness, mold or a ventilation problem.