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Humidifiers offer a simple way to improve your air quality. When used correctly, the best humidifiers alleviate issues associated with dry air, including allergies. But picking the wrong one could do more harm than good. According to Michael Brauer, Ph.D., professor at the University of British Columbia, improper use of humidifiers can lead to several air quality issues, including the development of mold, the accumulation of dust mites and the introduction of pathogens to your atmosphere.
We’ve scoured the market and tested extensively to find the four best humidifiers. These products make it easy to enhance your air quality without running into the negative health consequences noted by experts. Our top pick is the Levoit LV600S Smart Hybrid Ultrasonic Humidifier , due to its ability to automatically shut off when your preferred humidity is reached and its effortless cleaning procedure. If you’d like a luxurious alternative, consider the Dyson Purifier Humidify+Cool Formaldehyde PH04 , which serves as a tower fan and air purifier as well as a humidifier. It’s also remarkably easy to clean. Our lower-price alternative is the TaoTronics Cool Mist Humidifier , which offers many of the same features as the Levoit LV600S, though it doesn’t use the same premium materials. We also like Levoit’s Classic 300S Ultrasonic Smart Humidifier , which is great for babies thanks to a built-in night-light and other safety considerations.
The Levoit LV600S automatically turns off after reaching your preferred humidity and is easy to set up, refill and clean.
The Levoit LV600S Smart Hybrid Ultrasonic Humidifier offers everything you’d want from a humidifier, including important features that the competition lacks. The built-in humidistat is the most compelling reason to pick up the LV600S. This feature makes the humidifier automatically shut off when your home reaches your preferred humidity levels, unlike most humidifiers that continue to operate until you manually turn them off. This is important because excessive humidity can lead to poor air quality and mold growth.
Maintenance is always a pain point with humidifiers, as weekly cleaning cycles are often required. That holds true for the LV600S, but Levoit has done a good job of streamlining the process. After removing a few components, you’ll need to perform a vinegar wash followed by a bleach rinse. The pieces are easy to remove and clean and the large reservoir mouth makes it possible to reach every corner without needing to contort your hand into awkward positions. Once the humidifier is clean, all the components are easy to reinstall.
Unlike the reservoir, the humidifier base has quite a few nooks and crannies, but an included brush helps reach these less accessible areas. We found this model’s base to be a bit tedious to clean, but it’s still less cumbersome than others in this price range.
The LV600S’s simple setup takes just a few minutes. You can get it running by simply plugging it in and filling it with water. Its reservoir is removable and easy to fill thanks to the built-in handle and large mouth, and its transparent design lets you know when it’s time for a refill. Levoit has several buttons on the front of the device so you can access most of its features without a smartphone app, including a mist setting with multiple power levels and a humidity button that disables the device when a set level has been reached.
Designed to cover a room of up to 753 square feet, the LV600S uses a 6-liter tank and takes up quite a bit of space if you set it on a countertop—its footprint is 11.6 inches by 7.7 inches. Depending on how you use it, expect to get up to 50 hours of run time out of a single tank. Our experts note this lengthy run time would be an issue with other humidifiers that may run too long, but since the LV600S uses a humidistat to prevent excessive moisture accumulation, it’s less of a concern.
This humidifier supports both warm- and cool-mist operations, though we recommend sticking to cool mist to prevent the growth of mold and other pathogens. You’ll also find an inlet for essential oils if you’re interested in aromatherapy.
The LV600S works best with purified water. Using hard water could result in white dust accumulating on surfaces throughout your home. There’s no need to clean additional filters (though you can purchase mineral absorption pads to reduce mineral buildup), and the LV600S was one of the quietest humidifiers we tested. It was also one of the best-looking, thanks to a minimalist design that’s both stylish and practical.
If you love the idea of a connected smart home, you’ll be glad to hear the Levoit LV600S works with both Amazon Alexa and Google Home (Apple HomeKit is not currently supported). There’s also a surprisingly robust smartphone app , allowing you to check your settings remotely or create a schedule for your humidifier to follow during the day.
Functioning as a humidifier, air purifier, tower fan and air quality monitor, the Dyson is an all-in-one powerhouse.
The Dyson Purifier Humidify+Cool Formaldehyde PH04 costs more than the rest of the models we tested, but it’s much more than just a humidifier. Along with its ability to add moisture to the air, the PH04 serves as an air purifier and tower fan. You’ll also benefit from a built-in air quality monitor, which tracks real-time data about your home’s atmosphere and can be monitored remotely with your smartphone. The PH04 can even eliminate airborne formaldehyde , which can build up if you’re using gas stoves or if your home was built with wood products containing urea-formaldehyde (UF) resins.
The most compelling feature of the Dyson PH04 as a humidifier is its cleaning cycle. Unlike other humidifiers on this list that require vinegar and bleach rinses, Dyson uses citric acid powder . You’ll be alerted when it’s time to perform a cleaning cycle, which can be started by pressing the Deep Clean button on the front of the humidifier. From there, you simply remove the filter covers and the water tank, place the evaporator piece and citric acid into the tank, and then place the tank back into the humidifier. Once the cleaning cycle is done, you’ll be prompted to reinstall the evaporator and perform a water rinse. It takes an hour for the entire cycle to complete, but it’s largely a hands-off operation. Unlike with other humidifiers, there’s no need to scrub different areas with brushes or wedge your hands into reservoirs to perform manual cleaning.
As a humidifier, the Dyson PH04 is at the top of its class. Like all of our picks, it automatically shuts off when it hits your desired humidity. Its 1-gallon tank will get you up to 36 hours of run time before needing a refill. Water changes are simple; after unlocking the reservoir from the base of the Dyson PH04, you’ll be able to carry it over to a faucet with its built-in handle—no need for purified water. Once the tank is full, just snap it back into place and the humidifier will pick up where it left off.
The Dyson works just as well as a tower fan and air purifier . There are several fan settings, including 10 power modes and the option to oscillate up to 90 degrees. Its HEPA filter makes it a reliable air purifier, capturing most pollutants in your home and requiring infrequent filter changes (typically every 12 months). If you want to continue using it as an air purifier during cold winter months, you can enable a backward airflow mode to divert air through the back of the unit. Despite all these functions, we found the Dyson to be incredibly quiet and an ideal addition to a bedroom, thanks to a sleep timer that can be set to anywhere from 15 minutes to nine hours.
If you don’t mind its quirky design, the TaoTronics Cool Mist Humidifier offers many features typically reserved for higher-price gadgets.
Though it’s not made with the same high-quality materials found on other humidifiers on this list, the TaoTronics Cool Mist Humidifier offers several features uncommon for this lower price range. This includes an auto-off function to turn the device off once your set humidity is reached—a key feature recommended by our experts—and a sleep mode that disables the LED display.
Most lower-price humidifiers only let you adjust the mist power level. If unmonitored, this leads to over-humidification of your home, as they’ll continuously run until you manually intervene. The auto-off function of the TaoTronics Cool Mist Humidifier makes it an enticing device, as this functionality is typically reserved for higher-price alternatives. We also found it to be quiet during operation, though its buttons felt cheap and produced a loud clicky noise when pressed.
The TaoTronics’s design is rather quirky, with a translucent blue reservoir and aggressive contours that won’t be to everyone’s liking. Performing daily water changes was also a bit awkward, as you need to remove the reservoir and turn it upside down to access the opening. Cleaning the reservoir was more frustrating than with higher-price products due to a small reservoir opening, but its base was easy to wipe down due to minimal contours and crevices. Considering the TaoTronics Cool Mist Humidifier is one of the few in this price range offering an auto-off feature, these minor drawbacks are reasonable compromises.
The Levoit Classic 300S removes the warm mist option and adds a nightlight to make it an ideal humidifier for babies.
The Levoit Classic 300S is essentially a watered-down version of the Levoit LV600S. It benefits from the same premium construction and materials as its more expensive sibling, though it loses the ability to create warm mist while gaining a night-light. These two changes make it ideal for a baby’s room.
The lack of a warm-mist option is an important safety consideration and is crucial if you plan to use your humidifier around children. It’s unlikely a baby will knock a humidifier off a table, but if it does happen, the last thing you want is hot water in the tank. Since our experts weren’t keen on warm mist to begin with, losing the functionality can only be seen as a positive
Like the Levoit LV600S, the Classic 300S is easy to set up and operate. There are four buttons on the front of the device, allowing you to turn on the night-light, change your mist power levels, enter sleep mode or turn the device off entirely. The night-light is especially great for a baby’s room, as it’s bright enough to let you navigate without becoming obtrusive.
Weekly cleaning follows the same procedure as for most other ultrasonic humidifiers. This includes removing the float, water filter and noise silencer, then performing a vinegar rinse followed by a bleach rinse. We found this to be simpler than it was for the LV600S, as the lack of a heating element meant there were fewer components requiring a wipe down.
The Classic 300S also includes a powerful Auto Mode. Unlike the LV600S, which lets you pick a specific humidity level for your home, Auto Mode on the Classic 300S picks the levels for you. By default, enabling Auto Mode ensures your room stays at a humidity level between 40% and 50%. This can be adjusted using the smartphone app, but if you’re a busy parent, the ability to press a single button to optimize humidity levels is a big timesaver. Other notable features of the Levoit Classic 300S include a tray for aromatherapy, a sleep mode that turns off the display and support for Alexa and Google Home.
The Homedics TotalComfort Deluxe Large Room Ultrasonic Humidifier is a great option if style is at the top of your list. With a minimalist design composed of wooden legs and a streamlined white reservoir, the humidifier looks great in any room. It also feels more premium than many others in this price range. We found it cumbersome to clean due to its large size, though, and its elongated shape makes it a bit awkward to handle. It also costs more than our top pick, but it does automatically turn off when its water level is low or your set humidity is reached. Consider adding it to your list if you want a humidifier that looks a cut above the rest.
The Levoit Dual 200S is a solid lower-price pick, though it doesn’t feel as premium as other models in the Levoit lineup. It benefits from auto-off technology for low water levels and when your set humidity is reached when running in Auto Mode. Many of these settings must be adjusted using the smartphone app, but if you don’t mind its simplistic design, it’s a solid alternative to the TaoTronics Cool Mist Humidifier.
The Levoit 6000S Smart Evaporative Humidifier is designed for homes up to 3,000 square feet. Its reservoir is large enough to run for three days before needing a refill, though the size makes it cumbersome. Instead of filling it with a pitcher or placing it under a faucet, you’ll need to use an included funnel and tubing to direct water from the sink. We found the wheels to be difficult to maneuver on carpet, and with filters that need to be replaced at least twice a year (along with a lot of surface area to clean during routine maintenance), it requires more upkeep than other products we tested. Only consider it if you truly need a whole-home humidifier and don’t mind its size—most households will be better off opting for smaller humidifiers for each individual room.
We’d recommend steering clear of the Homedics Ultrasonic Humidifier designed for medium-size rooms, as it only includes auto-off functionality for a low water level and not preset humidity levels. This means it’s easy to over-humidify your home if you’re not paying close attention.
It’s a similar story for the Vicks 3-in-1 SleepyTime Humidifier and Crane 4-in-1 Drop Ultrasonic Cool-Mist Humidifier . Both are lower-price alternatives to the TaoTronics Cool Mist Humidifier, but because they won’t turn off when your preferred humidity is reached, the TaoTronics model is a better option.
I’ve been writing about consumer electronics for more than four years and have experience working in the biotechnology industry. I also have a background in biology and air quality from my past careers, along with a degree in biology. All this experience has helped me understand what to look for in products when deciding which ones have a real impact on your home’s air quality.
To augment my knowledge and learn more about humidifiers, I connected with three experts: Michael Brauer, Ph.D., a professor in the department of medicine at the University of British Columbia; John Straube, Ph.D., professor of civil and environmental engineering at the University of Waterloo; and Gráinne Cunniffe, Ph.D., the science lead at Allergy Standards Ltd, a global certification company. Their expertise helped identify important specifications for humidifiers, as well as guided our testing procedure.
Humidifiers are divided into two categories: ultrasonics and evaporatives. Ultrasonic humidifiers vibrate a metal or ceramic diaphragm to form water droplets, which are then dispersed into the air. They’re typically quieter than evaporative humidifiers and don’t use a filter, though you’ll need to use distilled or purified water to prevent the buildup of white dust on surfaces in your home. By contrast, evaporative humidifiers can use tap water and humidify the air by blowing dry air over a wet filter. These tend to be noisier than ultrasonics and are usually more frustrating to clean due to the presence of a filter.
Neither is better than the other, though many of the most popular models on the market tend to fall into the ultrasonic category, and most of the ones we recommend in this ranking are ultrasonic except for the Dyson. This is because most buyers prefer models that are quiet and easy to clean. And because most homes typically have purified or distilled water available, the lack of support for tap water isn’t a concern.
Straube says buyers should look for humidifiers with the smallest reservoir possible. This will prevent issues caused by over-humidification if it “runs amok” or its settings are tuned improperly.
All experts agreed that humidifiers need to be properly cleaned and should only be used with the type of water recommended by the manufacturer. Failure to follow these guidelines could introduce unwanted material, such as pathogens and minerals, into the atmosphere.
Based on that advice, here’s the list of criteria used to determine which humidifiers we tested:
With these criteria, we selected 11 humidifiers for testing. We tested by installing each humidifier, monitoring its performance and verifying each feature worked as intended (including the auto-off functionality for low-water levels and set humidity levels).
Once a product was installed and the features were tested, we then attempted to clean each product based on the manufacturer’s recommended guidelines. Products requiring us to remove fewer components or offering easier access were preferred over humidifiers that needed several components to be removed and reinstalled. It’s worth noting that humidifiers with warm-mist functionality tended to take longer to wipe down and clean because of the heating element and its associated hardware.
Cooling Water Tower Ultimately, our testing process looked for humidifiers that were easy to use and didn’t steal away our time. They should be able to work on their own without a babysitter, and forgetting about them shouldn’t result in over-humidification of your home.