Allergies, respiratory infections, dry skin, and uncomfortable colds may all be relieved with the soothing power of moist air from a cool-mist humidifier. Humidifiers create mist either by boiling, cooling, or atomizing water and circulating it throughout a room, increasing the humidity to soothe irritated skin, sinuses, and eyes while helping you to breathe easier. They feature reservoirs that hold up to 1.6 gallons of water, which they can convert into mist at a rate of up to 500 milliliters per hour (ml/h). Some models allow you to add essential oils for aromatherapy, and high-end smart units can be operated via an app or even voice control.
Cool-mist humidifiers are a newer type of humidifier, with particular advantages over their counterparts. Unlike warm-mist humidifiers, which use heat to boil water, cool-mist models rely on either a fan that draws air over a wick or ultrasonic vibration to create a cool mist. They are suitable for year-round use and safe for homes with small children, as there’s no heating element that could cause burns.
If you’re looking to raise the humidity level in your home, read on to learn more about these machines and to find out why the models below are among the best cool-mist humidifiers on the market.
- BEST OVERALL: TaoTronics Humidifiers for Bedroom
- BEST VALUE: MOVTIP Portable Mini Humidifier
- QUIETEST OPERATION: Pure Enrichment MistAire Cool Mist Humidifier
- BEST FOR LARGE ROOMS: LEVOIT Humidifiers for Large Room Bedroom
- BEST FOR ESSENTIAL OILS: GENIANI Smart Aroma Ultrasonic Humidifier
- BEST FOR NURSERIES: Crane Adorables Ultrasonic Cool Mist Humidifier
What to Consider When Choosing the Best Cool-Mist Humidifier
While shopping for a cool-mist humidifier for a room, there are several factors to consider, including type, intended use, and what advanced features are most important.
Type and Environment
Cool-mist humidifiers include evaporative and ultrasonic models, with some capable of functioning as both cool-mist and warm-mist humidifiers.
- Evaporative humidifiers: This type of humidifier uses evaporation to create humidity. A fan draws air into the unit, passes it through a wick or filter that adds moisture, then pushes the air back out into the room. One benefit evaporative humidifiers have over their ultrasonic counterparts is that they filter the water, eliminating impurities that can leave filmy residue on surfaces around the unit. They also won’t over-humidify the room (which can lead to unhealthy mold and mildew) because the evaporation process stops naturally once the surrounding air is saturated. The simplicity of these units makes them durable, but they do require significant maintenance, including a thorough cleaning at least once a week to prevent the growth of dangerous mold and bacteria.
- Ultrasonic humidifiers: This variety of cool-mist humidifier uses a vibrating diaphragm that sends tiny water particles into the air, providing more moisture than evaporative humidifiers. If not positioned high enough to allow the water particles to evaporate before hitting the floor, they can leave puddles on surfaces. Ultrasonic humidifiers can also over-humidify a room, promoting mold and mildew growth, though many models feature humidistats (devices that monitor and regulate the preferred amount of moisture in the air) that automatically shut off the unit when the humidity reaches more than 50 percent to prevent this problem.
- Warm-mist humidifier: Some cool-mist humidifiers can also function as warm-mist humidifiers. This kind of device works by boiling water to create steam that circulates through the air, raising the humidity. A warm-mist humidifier will saturate the room with humid air more than other types and also reduce the buildup of germs and bacteria in the tank due to its use of heat. However, since warm-mist units are capable of saturating the air more quickly and to a higher percentage than cool-mist models, they can cause mold growth in a room. They tend to be quieter than humidifiers that use fans, though they can be a fire or burn hazard since they use a heating element and boiling water.
Humidifiers have water reservoirs ranging from 500 milliliters for small travel models to up to 1.6 gallons for greater output. Most humidifiers will run between 15 and 60 hours before needing a refill.
Output, measured in milliliters of mist per hour (ml/hr), determines the size area a humidifier can fill. A humidifier that produces 180 ml/hr of mist can handle a room up to 270 square feet, while a 500 ml/hr humidifier will fill a space up to 750 square feet with moist air. For even greater capacity, consider a whole-home humidifier.
Filter-Free vs. Filtered
Many evaporative cool-mist humidifiers use filters to remove impurities from the water. These filters require regular cleaning and periodic replacement to prevent mold growth and clogging, which can be a hassle. Ultrasonic humidifiers do not use filters, so while they’re easier to maintain than evaporative models, they don’t filter out impurities and can leave a white dust on surfaces in the room. To prevent this issue, use distilled water in the unit.
Humidifiers have options that make them safer and easier to use. Most models have an auto-shutoff switch to prevent them from running with a low water supply, which can damage the unit. Some models offer a remote control to operate the device, while smart models operate via smartphone or even voice control when paired with a virtual assistant. Other features include tank indicators that let the user know when the water supply is running low and humidistats that adjust the mist output based on the room’s humidity level.
Intended use largely determines what type of humidifier is the better choice. For example, a humidifier in a nursery or young child’s bedroom should include an auto shutoff that prevents it from dry running, which can be a fire hazard. Night lights that can be turned on or off are also attractive features for kids’ rooms, as are units that run at low noise levels.
Some humidifiers include compartments for adding essential oils. This feature allows them to distribute calming or stimulating scents with the water vapor.
Although most humidifiers aren’t typically noisy, some work more quietly than others. Evaporative humidifiers operate around 40 decibels due to the fan that circulates air. Quiet-running ultrasonic humidifiers operate at about 26 decibels or lower, about the same level as a whisper.
Ease of Cleaning
Cleaning is essential to maintaining a humidifier. If mold and bacteria are allowed to grow inside the reservoir, those particles can be distributed into the air when the humidifier is running, creating a health hazard. As such, most humidifiers feature large reservoir openings that allow you to put your entire hand inside of the unit for easy cleaning. Some are even dishwasher safe.
Our Top Picks
The optimal humidity level for healthy air is 50 percent, according to the Environmental Protection Agency. The humidifiers below will help your home reach that sweet spot. They have high mist outputs, auto-shutoff features, easy-to-clean designs, and other important features that make them among the best cool-mist humidifiers on the market.
This model from TaoTronics will please those who prefer the sensation of cool mist as well as those who favor the soothing heat of warm air. It provides warm or cool mist at a rate of 550 ml/hr, making it capable of handling rooms up to 750 square feet. Dual nozzles allow the user to direct moist air in two directions, and the 6-liter tank provides enough water for up to 60 hours of continuous operation.
This humidifier also features a sleek design with touch controls and an easy-to-read LED display of the current humidity level. A remote control lets the user make adjustments without leaving the bed, while an essential-oil tray allows for aromatherapy. The big opening on the reservoir makes cleaning easy.
If you’re looking for an inexpensive and conveniently portable way of breathing easier, consider this MOVTIP model. At 5 inches tall, 3 inches wide, and just 10 ounces in weight, this humidifier is small enough to carry easily in a suitcase or backpack. It’s powered through a USB connection and features a 500-ml tank, allowing it to continuously spray for up to 12 hours or intermittently for up to 18 hours.
With an output of 30 to 50 ml/hour, it can humidify about 200 square feet. The auto shutoff will power down the dehumidifier when the tank is empty. The entire top of the unit opens to expose the reservoir, making it easy to clean.
For those sensitive to intrusive sounds, this whisper-quiet humidifier might be the right choice. It’s quiet enough that it shouldn’t disturb anyone in the room, whether they’re sleeping, studying, or watching TV. An auto shutoff prevents this model from running when empty, while an optional night-light provides a gentle blue glow. An LED indicator turns from green to red when the water level gets low.
This Pure Enrichment humidifier has an output of 150 ml/h, making it suitable for spaces up to 270 square feet. It features high and low mist settings and a nozzle that rotates 360 degrees for directing the flow of mist. It features a 1.5-liter tank, so it will only run for up to 16 hours. The tank’s small opening makes this unit difficult to clean, so plan on using distilled water to prevent the growth of mold and bacteria.
Maintaining a comfortable humidity level in a large space can be a challenge. With its 500 ml/h output, this model from LEVOIT can cover areas up to 750 square feet. It features a sizable 1.5-gallon reservoir that provides up to 60 hours of continuous use. Features include a sensor that automatically adjusts the humidity level and an auto shutoff that turns the unit off when the water level is low.
A remote control allows the user to adjust the settings from afar and there’s a 1-to-12-hour timer, so forgetting to shut it off isn’t a problem. Quiet operation and a display that can be turned off make this a good option for the bedroom. A wide opening in the reservoir makes refilling and cleaning easy.
Breathe easy while enjoying the effects of aromatherapy with this GENIANI combination humidifier and diffuser. It includes a small pad that holds essential oils, allowing the unit to distribute the scent along with mist for up to 18 hours.
A convenient top-fill design allows the user to load the reservoir without having to remove it from the base. An internal sensor assesses the room’s humidity level and adjusts damp-air output based on a low, medium, or high setting. The unit features a 1-gallon tank to cover up to 220 square feet, and its night-light can be turned off if light sleepers find it distracting.
Monkeys and hippos and frogs, oh my! Featuring 14 fun animal designs, this cool-mist ultrasonic humidifier fits well into a baby’s nursery. With its ultrasonic technology, the Crane model operates more quietly than the sound of a whisper. A soft white light can function as a night-light or be turned off if it’s a distraction. A large dial allows the user to adjust the output, and an optional filter removes impurities before vaporizing the water.
The auto-shutoff feature turns the humidifier off when it detects low water levels. With a 1-gallon capacity, this humidifier will run for up to 24 hours before needing a refill. It features two output nozzles, which allow it to handle spaces up to 500 square feet.
The Advantages of Owning a Cool-Mist Humidifier
There are various good health benefits to owning a cool-mist humidifier. These devices increase the humidity in a room, soothing sinuses and making it easier to breathe. They are especially beneficial to those who suffer from allergies or who are experiencing sinus congestion due to a cold. Humidifiers also help those who suffer from xerosis, dry eyes, cracked lips, and bloody noses by adding moisture to the air that hydrates the skin and nasal passages.
A good cool-mist humidifier:
- helps relieve allergy symptoms
- alleviates congestion caused by a cold
- can help moisturize dry skin
- alleviates eye irritation from dryness
FAQs About Cool-Mist Humidifiers
Still wondering about how humidifiers work or which type is best for what situation? Read on for answers to the most commonly asked questions about these devices.
Q. What are the benefits of a warm-mist humidifier?
Most people prefer warm mist during colder seasons and cool mist for warmer seasons. Since warm mist uses boiling water, it is better for preventing the growth of mold and bacteria in the humidifier. However, that boiling water is a burn risk that makes them less suitable for children’s rooms.
Q. Does a humidifier help with shortness of breath?
A humidifier can ease shortness of breath caused by asthma and other respiratory diseases by easing congestion and opening up air passages. However, over-humidifying a space or using a dirty humidifier can cause mold growth and/or distribute mold spores into the air, aggravating respiratory problems.
Q. Do humidifiers help with allergies?
Humidifiers can help those with allergies, but only when the humidifier is used and cleaned properly.
Q. Should humidifiers run all night?
When monitoring the humidity levels in a home or using a humidifier that measures those levels, it’s OK to run the humidifier all night as long as it has an auto-shutoff feature that prevents it from running dry, which could create a fire hazard or damage the unit.
Q. Can I over-humidify a room?
This depends on the type of humidifier. An evaporative humidifier can only add moisture to the air up to a certain humidity level before it will no longer increase the humidity, typically around 50 or 60 percent. An ultrasonic humidifier can over-humidify a room if left unmonitored, causing moisture to collect on the floor or the walls.