GermGuardian HEPA Air Purifier Tower - 22" - Gray - AC4825E

Why it's worth it

This slim tower is the least demanding way to get true HEPA and a carbon layer into a litter box room or a small bedroom. It's rated for a single air change per hour in about 743 square feet, but the honest working number is a good deal smaller than that.

Put this in the spare room where the litter box lives and it does the job you bought it for. The 22-inch tower is under seven inches wide, so it slots between a dresser and a wall without anyone tripping over it. GermGuardian rates it to filter a 153-square-foot bedroom about every 12 and a half minutes, which is meaningful turnover for a space that size.

It has the two things that actually matter and skips the rest. A HEPA filter rated at 99.97 percent capture, and a separate activated carbon layer for cooking and pet smells. Published lab comparisons keep landing on the same point: without that carbon stage, odor intensity doesn't measurably drop, however good the particle filtration is. Plenty of pricier purifiers still ship without one.

From our review of 5 pet air purifiers

What we like

• +Put this in the spare room where the litter box lives and it does the job you bought it for
• +It has the two things that actually matter and skips the rest
• +The UV-C lamp is the part to stay neutral about

What to know

• –The coverage claim oversells it
• –It's also a plainer machine than the picks above