Blueair’s DreamWell Humidifier has several features to make this one of the easier humidifiers to use and maintain. Blueair makes the DreamWell in both 1- and 2-gallon tank sizes. WIRED tested the 1-gallon model. The DreamWell has mood lighting (warm, normal, and bright), along with a scent pod that can be filled with a few drops of essential oil that turns this humidifier into a sleep aid. Its understated design blends into most interiors. Similar to Blueair’s Signature air purifier, I found the DreamWell’s control panel difficult to see in bright light. What the control panel lacks, Blueair’s advanced app makes up for. Blueair has a “welcome home” function that uses geolocation to turn the humidifier on 15 minutes before the user walks in the front door. In using the feature, the user needs to plug in their mode of transportation: walking, biking, public transport, or car. There’s also an option for drying the wick, the humidifier’s machine-washable filter, which starts automatically when the tank is empty.

The DreamWell comes in Coastal Beige or Stone Gray and is the ideal size for a small bedroom. For larger rooms, go for the 2-gallon DreamWell. And while the tank is only 1 gallon, the fill-top option makes for easy refilling.

This is an ideal air purifier and humidifier for a small room no bigger than 300 square feet. The 2-in-1 uses HEPA and carbon filters to pull both PM 2.5 and VOCs (volatile organic compounds) from the air. There’s an air sensor that corresponds with the purifier’s indicator light. Blueair has custom light codes that I find confusing: blue for excellent, green for very good, yellow for good (yellow usually means moderate in US AQI color codes), orange for polluted, and red for very polluted. And while the indicator light might take some getting used to, the Blueair app is excellent. The 2-in-1 also has the “welcome home” geolocation feature that automatically turns on the appliance 15 minutes before you walk in your front door. It also has both the air quality and humidity readings.

For an appliance that is 3 feet tall, the humidifier’s tank is surprisingly small at 0.79 gallons. The option of using the top-pour design at least makes the task of refilling the tank relatively easy. If you are short on space and want to combine your air purifier and humidifier, then Blueair’s 2-in-1 is an excellent choice.

Dreo knows how to make smart home appliances and has one of the most user-friendly apps I’ve tested. This humidifier pairs easily, and I’m able to preset everything from humidity levels to the color of the lights. The Dreo has become my default nightlight as it illuminates my dining room with the soft glow of its ambient light coordinated to various settings: blue for “wet,” aqua green for “comfort,” and orange for “dry.” The more I review air quality appliances, the more I appreciate the quick intel that color codes provide.

The built-in humidistat and easy-to-read LED display let me see my room’s humidity percentage. And as much as I love the Dreo Smart Humidifier, it’s annoying that it doesn’t come with a filter and that it needs to be ordered separately. Dreo is not the only model that does this, but it’s an unnecessary additional step. On the positive side, you can monitor the filter life in the Dreo app along with the cartridge life indicator light on the built-in display. And having a filter is especially important if you’re like me and only use tap water. The Dreo also has an aroma pad tray for essential oils. Lastly, the Dreo has a generously sized water tank that is filled from the top along with three directions for mist, including straight up in the air. I appreciate this last feature, as it means the Dreo caan be placed directly on the floor.

The Dreo has one of the longest run times—nearly 100 hours—of any humidifier WIRED has tested. That large tank solves one of the main complaints I hear from humidifier users: the need for frequent refills. Keeping a humidifier stocked with water is much like watering a thirsty plant: Humidifiers often require daily attention. The Dreo’s nearly 3-gallon tank eliminates that. Still, that large water tank comes with some downsides. The Dreo Smart without water weighs a light 6 pounds, but when the water tank is at capacity, it weighs a difficult-to-carry 28 pounds. Standing at 2.5 feet tall, the humidifier’s long, rectangular tank also limits the kind of faucet/spigot that can be used to fill it. There is a pour-over option, but it requires three 1-gallon pitchers of water to fill the tank. The other issue with a long and tall humidifier—and perhaps this is only an issue for cat owners—is the possibility of tipping over. It didn’t tip during testing in a two-cat household, but I did worry about the possibility.

The Dreo Smart is a well-priced whole-house humidifier, up to 700 square feet, with a mist over 6 feet high. Its seamless, intuitive app gives users complete control over maintaining humidity at the preferred setting. There is also an aroma pad tray for those who want to use a few drops of essential oil in their mist, turning the humidifier into a giant air diffuser. The Dreo Smart’s humidity indicator light glows yellow when humidity is lower than 30 percent, green for 31 to 60 percent, and blue for 61 percent and above. According to the EPA, ideal indoor humidity is between 30 and 50 percent.

I tested this old-school, energy-efficient portable humidifier in my home, but realized its true potential when I woke up with a dry and almost bloody nose while staying in a California hotel. I had been living in ideal humidity back in New York City. As I sprayed saline up my nose, I had a single thought in my mind: I should have brought a humidifier. Around the size of a rectangular box of tissues or toiletry case, the Homedics Ultrasonic is not too large and deserves space in my luggage. But unlike so many petite humidifiers, its nearly 2-liter tank can effectively add humidity to a 258-square-foot room, making it perfect for bedrooms and hotel rooms.

The Ultrasonic looks like the humidifiers I bought for my kids’ rooms when they were babies, but it has added features like the small plastic capsule that is Homedics’ “demineralization cartridge.” And, being a Homedics product, it also has an essential oil tray and pads. I’ve used the Homedics essential oil tray before with the brand’s air purifier. Essential oils in the Homedics tray didn’t negatively impact my indoor air quality, according to my air quality monitors, but pet owners might want to skip this feature, as essential oils are not considered pet-safe. Lastly, the Ultrasonic has a built-in seven-color glowing nightlight. This option is especially useful in a child’s room or unfamiliar hotel room.

Note: this product is temporarily out of stock.

The Carepod One is suited for a room around 500 square feet. It has a stainless steel tank and a flat bottom that gives off a rice cooker vibe. It also has fewer features than its larger Carepod siblings—no sensor, auto mode, heat, or sterilization, but there is a timer for four, six, and eight hours, along with three levels of mist.

The Carepod One is inexpensive and solid, with out-from-the-side mist, and was effective at giving my den ideal moisture. On the down side, I’m not sure if it would work in a typical bedroom; for example, mine is around 200 square feet. It also needs to be at least 2 feet off the floor. Unfortunately, neither of the Carepod stand accessories fit the Carepod One. Still, the Carepod One might be just the right size to sit on a stool.

The Natura by Homedics has several novel elements new to the humidifier market. First, it’s made with recycled materials and FSC-certified bamboo, meaning that the bamboo was harvested from responsibly managed forests. And second, the Natura has a pot for a plant (for aesthetics). Beyond that, the Natura has several features that also make it a versatile humidifier for large rooms, like a living room. And while the Natura isn’t app compatible, it has a built-in humidistat, an easy-to-see digital display, auto mode, five mist levels, warm or cool mist, a timer, and a light.

The Natura also has two options for filling the water tank. You can use a pitcher to fill the Natura from the top or pull out the water tank from the side and fill it directly from the faucet. The tank method is actually the quickest. There is a caveat—I like a top-filled tank, but after I potted my plant, I could see how soil from the plant could fall into the water tank through the top-fill water drain. Still, I liked the different look of the Natura; it’s a pleasant shade of beige. Though unlike some of the humidifiers I’ve tested, there is a very clear front and back to the Natura. And while the mist spout can be rotated for custom spray directions, I moved my Natura around to avoid misting my couch; that left me looking at its backside. And like all the Homedics appliances I’ve tested, it also includes the essential oil aroma tray. If you don’t want a plant growing out of your humidifier, you can put the bamboo cover over the planter and have a side table for your cup of coffee.

The Levoit Dual 150 is both small and easy to maintain and use. And while it’s not app-compatible, its 3-liter tank and easy-to-use dial deliver a solid mist that can keep a small bedroom at perfect humidity through the night. For under $50, the Levoit might be the ideal humidifier for the dorm room or nursery.

Levoit is also a top-fill humidifier, which makes filling the tank especially easy. The company also pitches its humidifier as an essential oil diffuser. It recommends adding 10 to 20 drops of essential oils directly into the base chamber. Diffuser lovers may be buying the Levoit for exactly this purpose, but because there are no pads on which to apply the oil, users may find it difficult to fully remove scents. The Levoit made me appreciate the impermanence of the essential aroma pad trays found in other models, as the Levoit’s method seemed permanent. If I no longer want geranium filling my bedroom, I had no way to remove all of the essential oil and its residue from the base chamber. And while Levoit recommends cleaning the humidifier every three weeks, it does not recommend using detergent, so it’s water only. The Levoit comes with a filter, but mine yellowed after two weeks and will most likely need to be changed even more often when using essential oils. That said, you can buy a 10-pack of Levoit filters for under $15. And with the Ultrasonic’s two-year warranty, you have one of the best cost-to-use ratios you can find in a humidifier.