How long does the tank last?

Optimus rates it at about 8 hours per fill. In practice that is roughly one night, so expect to refill daily in dry weather.

Does it shut off by itself?

Yes. It has automatic shutdown that cuts the mist when the water level gets too low.

Ultrasonic humidifiers can throw mineral dust from hard tap water. Use distilled or filtered water to avoid a film on furniture.

No. This model has no humidistat or mist-level control, so it runs until you turn it off or the tank empties.

Its small output and 1.4-gallon tank suit a single bedroom, nursery or office rather than a large open room.

No. It is a filter-free ultrasonic design, so there are no replacement filter costs.

5 stores we checked sell it, including Tractor Supply Co, Newegg, Best Buy, Shop Simon, Lowe's.

At Tractor Supply Co, for $36.99, 39% under what the other stores charge, as of our latest check.

$36.99at Tractor Supply CoChecked 13 h ago

39% under what the other stores charge

Compared across 5 stores. Prices are checked against each store and labelled with when. Store links may earn us a commission. Price via Klarna.

It checks today's price at every store, compares the alternatives and answers in about a minute.