Cool Mist vs. Warm Mist Humidifiers: What's the Difference?

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Each winter, as the air becomes dry both inside and out, you might notice an uptick in things like a cough, sore throat, headaches, chapped lips, and dry skin and hair. The cold weather outside paired with the introduction of our indoor heaters that leave little moisture behind creates the perfect conditions for these dry-air problems.


To counteract the dryness and get ahead of the problems caused by it, many turn to humidifiers, which work to add moisture to the air. Humidifiers have been shown to help with a number of things, including alleviating allergies, sinuses, and coughs, protecting from the seasonal flu and the common cold, reducing snoring, and maintaining moisture in the hair and skin. And for those with asthma, humidifiers can help maintain the 30 to 50% humidity level, which is considered a good, healthy level for those with this respiratory issue.


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When shopping for this product, you'll notice two main types of humidifiers: Cool mist humidifiers and warm mist humidifiers. Cool mist humidifiers release a room-temperature mist in the home, while warm mist humidifiers boil the water and release it as steam, resulting in a hotter mister.

Below, we'll dive further into each type of humidifier, its benefits, and which one might work best for you.


Cool Mist vs. Warm Mist Humidifiers

Cool Mist Humidifiers

As was mentioned, cool mist humidifiers release a room-temperature mist, which is done by using one of two technologies: evaporative or ultrasonic.


Evaporative humidifiers utilize a built-in wick and fan to increase the rate at which water evaporates. Once evaporated, this type of cool mist humidifier blows the water into the home as a fine mist, humidifying the air. Alternatively, ultrasonic humidifiers create vibrations in the water, resulting in mist.

While evaporative humidifiers tend to be cheaper, ultrasonic humidifiers require no filter changing and emit next to no noise. They are also often smaller, as evaporative humidifiers require space for fans. However, evaporative humidifiers do trap more mineral scale than their counterpart.


As a whole, cool humidifiers offer a range of benefits. They cater to larger spaces, making them perfect for living rooms and other communal areas. They effectively add humidity to the air, oftentimes using less electricity than their warm mist counterparts, and are typically safer for those living with pets and young ones.

With that said, a cool mist humidifier can be on the noisier side, especially if opting for an evaporative humidifier. Additionally, the cool mist can cause already chilly air to feel even more so.



Our Favorite Cool Mist Humidifiers

1. Vicks Filter-Free Cool Mist Humidifier, $46.99

2. Objecto H3 Hybrid Humidifier, $150


3. BreatheFrida 3-in-1 Humidifier, $49.99


4. Hupro Ultrasonic Humidifier, $99.98


Warm Mist Humidifiers

Warm mist humidifiers work differently than cool mist, as they function through a heating element and the use of hot water. With a warm mist humidifier, the water boils inside before being released into the room as steamed water vapor.



Warm mist humidifiers are often viewed as healthier, given that the boiling process kills bacteria and germs present in the water. This differs pretty dramatically from a cool mist, where distilled, already-boiled water is recommended for user safety and experience.

Additionally, warm mist humidifiers add warmth to the air, a serious bonus come winter months, as well as higher levels of moisture saturation. This makes them great for dry skin and seasonal colds, coughs, and sore throats.

The downside? Warm mist humidifiers do not cater to larger spaces, use more electricity, and are not recommended for families with young children and pets, as the boiling water can present safety risks.

But if your child-free bedroom needs some humidity in the air this winter (as well as extra warmth), a warm mist humidifier will effectively do the job.

Our Favorite Warm Mist Humidifiers

1. Vicks Warm Moisture Humidifier, $42.99

2. Honeywell Warm Moisture Humidifier, $50.09

3. Crane Warm Mist Humidifier, $49.99


Warm vs. Cold: What’s Right for You?

What's right for you depends on both your home and your needs. Both cold mist and warm mist humidifiers will help with dry skin and hair, open nasal passages, and keep sore throats at bay. However, they aren't necessarily meant for the same home.

Warm mist humidifiers are perfect for small, pet and child-free spaces. They are incredibly effective in terms of moisture saturation (more so than most cool mist humidifiers) and have the ability to add a little extra warmth to a room. Their water-cleaning, boiling process also makes them great for those with allergies or sensitives to bacteria. However, that same hot water makes them unsafe for children.

A cool mist humidifier is ideal for larger spaces and homes that require year-round humidification (you're not going to want hot steam come summer). They are also family-friendly and use less electricity than their warm-mist counterparts.



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