The evaporative Honeywell HCM-350 Germ-Free Cool Mist Humidifier has been our pick since 2015. It has outperformed more than two dozen competitors in round after round of tests. And in all that time, we haven’t uncovered serious flaws in any of the nine units that Wirecutter staffers have tested across the country. That’s because the HCM-350 does almost everything right: It humidifies the air quickly, runs quietly, maintains a comfortable moisture level, and doesn’t beep or blink at night. Its durable tank is extremely easy to fill and clean, with parts that you can run through the dishwasher. Good for spaces as large as 400 square feet, the HCM-350 works fine for most bedrooms and living rooms. And because it’s an evaporative humidifier, this model can’t over-humidify the air or spread white mineral dust the way ultrasonic humidifiers can. Our only real complaint about the HCM-350—in addition to having to clean it, as you do with any humidifier—is that it requires a wick replacement every few months, which adds a small but annoying ongoing cost.
The Levoit LV600HH Hybrid Ultrasonic Humidifier is our pick for large spaces and exceptionally dry, demanding environments, because its powerful ultrasonic mechanism provides continuous humidification, whereas evaporative models level off once a certain humidity level is reached. Unlike most ultrasonics, the LV600HH is less likely to over-humidify a room, thanks to a built-in humidistat that’s accurate enough to regulate its output. The humidifier’s big, 6-liter/1.5-gallon tank can go more than 24 hours between refills. This model is exceptionally quiet, but like other ultrasonic models, the LV600HH has an audible hum that can be annoying if you’re sitting or sleeping within a few feet of it. And this model can occasionally leave behind a puddle of misted water or a thin layer of white mineral dust, which can also be annoying, but’s easy to clean up or avoid.
With a single control dial on its attractive black tower base, the Honeywell HUL430B Cool Mist Humidifier is simple but effective. By the two-hour mark in our tests, this model raised the room’s moisture level more than nearly every competitor—almost too much. (The HUL430B shares this over-humidification risk with many similar ultrasonic models that lack a built-in humidistat, as this one does.) This model stands out for its sleek design—it’s one of the few genuinely attractive humidifiers—and for being virtually silent (aside from a slight mechanical hum). The HUL430B also emits an optional gentle white glow, which we found to be rather pleasant; even more convenient is that it turns orange to let you know when the water is running low. Its 1.25-gallon tank does have one part that’s difficult to reach around, so the HUL430B is not quite as easy to clean as the Levoit LV600HH.
If you just need a basic humidifier that looks nice and does the job without costing too much, gets the Levoit Classic 200 Ultrasonic Cool Mist Humidifier—even though it has a tendency to over-humidify the room, like all ultrasonics. Its 4-liter tank is actually slightly bigger than the tank on the Honeywell HCM-350, with a large opening and simple rectangular shape that makes it easy to clean. The Classic 200 isn’t quite as versatile as the LV600HH—it has just a single button that changes color each time you press it, to indicate the different power levels (on/low, medium, high, and then off again). It also lacks a humidistat or any other option for self-regulation. Otherwise, the Levoit Classic 200 has all of the same perks and flaws as many ultrasonic humidifiers, including quiet but buzzy operation and a slight chance of water puddling underneath.
If you want an extremely effective evaporative humidifier that requires less-frequent cleaning and refilling than our other recommendations, consider the Venta LW25 Airwasher. At its current price of around $300, it is very expensive, but its high up-front cost is somewhat mitigated by its extreme energy efficiency in the long run. And in our tests, the LW25 consistently ranked high in humidification performance. Like our other evaporative picks, this model is suited to spaces that are the size of a large bedroom. Competitors require weekly cleaning. But Venta recommends that you rinse this unit every two weeks and thoroughly clean it every six months. However, despite its name, it does not wash the air particularly well; if that’s a concern for you, consider getting an air purifier.
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