Cool Mist vs Warm Mist Humidifier

Humidifiers are the best way to add humidity to your living spaces when dry climates, seasonal allergies, or respiratory issues have you struggling to breathe. They also have a variety of benefits to help keep your environment healthier and clear of dust and allergens, as well as adding moisture to the air to help aid in furniture and plant care.

If you are tired of dry skin, staticy floors and sheets, and breathing issues- you definitely want to explore your humidifier choices. So which is best? A cool mist humidifier or a warm mist humidifier? Take a look at our breakdown of cool mist vs warm mist options to help you decide which type is best for you.

Cool Mist Humidifier

Cool mist humidifiers are amongst the most popular as they can change the moisture level of a larger room, introduce a water vapor that is at or cooler than room temperature, and many also double as a diffuser to take advantage of your favorite essential oils. They are considered the safest choice for young children and babies as well.

These types of humidifiers are usually evaporative, meaning they use a filter or wick to draw up water which is then distributed through a room with a fan; or are ultrasonic and use an ultrasonic vibration plate to create tiny water droplets that also are distributed in a similar manner.

Pros Cons
  • Safe for kids and pets
  • Energy efficient
  • Covers a larger area than a warm mist
  • Overall more loud than a warm mist
  • Can accumulate mold and mildew and needs more cleaning

— Benefits

Cool mist humidifiers begin distributing moisture quickly, and can cover large areas based on the size and specifications of the unit. If you have a large bedroom or living area that would benefit from moisture, this is a great choice.

Any humidifier provides dryness relief, and helps keep allergies and dry skin away. It also is healthy for indoor plants and can work to extend the life of your wood furniture. Plus, many offer the ability to use essential oil diffusion, which can work to help alleviate airborne bacteria and viruses, and naturally scent your space.

Cool mist models are also very safe for children and pets as no hot water or steam will be a concern. They also have a tendency to be amongst the most affordable options to both purchase and run.

— Concerns

Cool mist units aren’t perfect, however, and the noise from the fan can be bothersome to some people and may be disruptive at night. There are many types that claim to be whisper quiet, so be sure to research those if sound might be an issue. They also need to be regularly cleaned and rinsed to avoid mildew and bacteria buildup, which can be a major concern. Hard water buildup is also common, so it is suggested to use distilled water, or regular soak in vinegar to remove any deposits.


Warm Mist Humidifier

Warm mist humidifiers use a heating element that boils water internally, and then releases the heated steam to add moisture to the environment. Since they do not use a fan due to the forced pressure caused by the steam, they are quieter, and are popular in colder climates as they can help warm the air. The design is conducive for use with inhaled medicines as well- both OTC and prescribed.

Pros Cons
  • Best for reducing bacteria and germ  in the environment
  • Quieter than a cool mist
  • Can warm a room
  • Uses more energy than a cool mist
  • Poses a hazard due to hot steam and water
  • Doesn’t cover large areas well

— Benefits

Just like a cool mist humidifier, warm mist humidifiers help with dryness relief and can work to provide allergy and dry skin soothing properties. They support indoor plant life and furniture care as well.

They also are better for bacterial and viral infections that may be circulating since the heated air can be warm enough to kill certain airborne issues. Plus, their use with specific inhalants, such as chest medication and even essential oils work to help clear up respiratory issues more quickly than a cool mist unit.

Another reason why they are well liked is how quiet they are. They do not have an internal fan, and so they create little to no noise.

— Concerns

The heat of a warm mist unit is a big concern, especially if you have children or pets. It can tip without care, or create burn scenarios from the steam on young, delicate skin if they get too close to the origin.

As for coverage, they are more specific to small room, or bedside use and do not work as well in large areas.

They also cost more to buy, and draw much more energy than a cool mist unit. In order to heat the water, the element must be brought to a high temperature that draws a lot of energy. Also, like the cool mist options, they need to be cleaned regularly and can actually build up with hard water and mineral residue easily due to the boiling process. They aren’t as easy to clean either due to the care you have to take with the heating elements.

Your Best Choice Explained

Honestly, your best pick is going to be the one that you feel is best for your space and scenario. Both are very effective and good at what they are made for. With that being said, a cool mist humidifier outsells the warm mist units more often due to the space they can cover, the ease and safety of use, and the versatility. Small warm mist units are best saved for breathing issue solutions and similar.

Cool Mist Warm Mist
  • Affordable and easy to use
  • Uses cool water vapor 
  • Safe for use near pets and children
  • Some designs work as a diffuser also
  • Most costly, but very effective
  • Uses hot steam from boiled water
  • Can be a hazard to children and pets
  • Many can be used with medicine and essential oils


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