How we review

Every guide follows the same process, so a budget purifier and a premium one are compared on the same terms.

Our editorial process

We build a shortlist from models currently sold in the US, then compare them on the same set of specs. Each pick gets a "Best for" line naming the room or problem it suits. Products we can't verify, or that are no longer sold, come off the list.

Published specs and running costs

We use manufacturer specs and public certification data. For air purifiers, that means CADR and AHAM room-size ratings, plus CARB certification for ozone emissions. For dehumidifiers, it means pints per day and ENERGY STAR efficiency. We add the yearly cost of replacement filters and electricity, so the price on the box isn't the only number you see.

Real-room fit and updates

A purifier rated for a large room may only keep up in a smaller one on its quiet setting. We match each pick to a realistic room size and note the noise level at that setting. When a model is discontinued, a filter price changes, or a newer version replaces it, we update the guide and the date at the top.