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Rosewill Ultrasonic Cool Mist Humidifier Review: The Best Humidifier for Bedroom

Modern humidifiers tend to be noiseless, long-lasting and with big capacity in order to be able to bring humidity to any room of your liking. Such is the Rosewill Ultrasonic Cool Mist Humidifier. Designed especially for bedroom, this humidifier is supposed to give you a full night of relaxed sleep, while at the same time being aesthetically pleasing with its blue night light that is made to bring you even more calmness during long, dry nights. With all this in mind, we have decided to test this unit so we could see if it really stands up to its claims.


This is definitely one of the “bigger small humidifiers” on the market. It has an astonishing capacity of 1.32 gallons (5 liters) of water, which is almost 50% more than your average humidifier. However, due to its strong misting power, this unit can hold up to no more than 24 hours of uninterrupted work, which is not quite longer than some other humidifiers can handle, despite them having a capacity of around 1 gallon of liquid. Still, it makes up for it with how quickly it can bring moisture to any medium to large-sized room, so there really isn’t the need to keep it on for any longer.

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Rosewill Ultrasonic Humidifier also has a transparent tank, which means that you will easily see the amount of water that is left without having to open it up or to search for small level bars.

Also, its filter-free design makes for easy maintenance, so you won’t have to worry about changing filters after almost every use like you normally would.


The ultrasonic technology makes this unit work at a noise that doesn’t go over 32 decibels, making it virtually soundless. You won’t even hear it working, which is why it is being advertised as the best humidifier for your bedroom of any size. We would also like to add that the no-noise factor makes it perfect for your nursery room, as you can be sure that it won’t disturb your children’s sleep, no matter how restless they tend to be. Not only that but as it will add freshness to the room, it may also make them fall asleep faster and easier, which will, in return, also make your evenings more relaxing.

At the same time, this unit has a built-in soft-glow LED light in blue color that has a positive and calming effect on your brain. Together with the ultrasonic technology, this is to ensure that you can have a full night of relaxing sleep.


The unit is made with your bedroom in mind, so it can cover almost any medium to a large interior, perfect for any sleeping space. The manual makes it precise in stating that it works best in rooms that are up to 250 square feet in size, and we can confirm that this is true and that the sizing isn’t overstated.

In order to make your sleep even more pleasant, it has two completely moveable nozzles that can rotate for 360 degrees and allow for two streams of mist – or they can be combined into one stronger stream if you’d prefer it that way. Also, the volume of the misting is adjustable, so you can fully set the humidity levels to your liking. The water level will most likely not go down quickly even when put on stronger misting volume, and even if that does happen there exists the automatic shut-down option so don’t expect any malfunctions even if you forget to turn it off during the night.

How Does It Stand Out?

5l tank

The unit has one of the biggest water capacities when it comes to the filter-free humidifiers. This means that you can say goodbye to the constant water changing and nonstop checking the reservoir levels.

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Night light

The soft, blue light will soothe you and give you a relaxing night experience without disturbing your sleep. It can be turned off though if you prefer the darkness.

Two adjustable nozzles

This device has not one, but TWO rotating mist nozzles to give you full control of the misting direction.


What is the white residue that can be found in the room after using this humidifier?

Don’t worry; the powdery residue is just from minerals in your water. If that bothers you, use distilled or filtered water instead.

Can I use essential oils with it?

No, it is not recommended that you use any kind of essential oils in this humidifier, as it can cause malfunction.

Will it emit a cold or a warm mist?

This is a cool-mist humidifier, which means that it is supposed to be used with cold tap or distilled water only, and it will emit a cold, refreshing mist.

Is it easy to clean?

The center column is a bit harder to reach unless you have a long, narrow brush. However, you can always use vinegar with warm water to clean those parts. Other than that, the opening is large and you shouldn’t have any problems cleaning it.

How long can it run on one filling?

It depends on your volume settings. If on high, one filling can last for 8-12 hours, and if on low it can hold out for an entire day.

Does it need daily maintenance?

While it is recommended that you clean it every time you refill it, it is usually enough to just rinse it and then clean it up with more detail every week.

How big is it?

This unit is approximately 10 inches high and just a little less than 5 pounds heavy when empty.


Taking everything into consideration, we can confirm that this is indeed one of the better humidifiers for your bedroom. It can last for a whole night, and it’s moveable nuzzles will help you point the mist output into any direction, so you can either enjoy being on a direct hit of a stream, or you can move the humidity source to another direction so it doesn’t disturb your sleep.

It also has a LED night light that will help you fall asleep easier, and it will also provide a small but sufficient light source in case you wake up during the night. Its large capacity is made for long-lasting work hours, but the downside of this is that the unit tends to be heavy when full so it is harder to move around. Also, it has an automatic shut down option, so you can sleep soundly knowing that it will turn off if the water level depletes. The only problem is that it doesn’t support essential oils, but for the price, this really isn’t a big deal.

In short, this humidifier will surely help you breathe better at any time of day, any time of the year.

if this humidifier is not what you were looking for, check out our Best Filterless Humidifiers post.

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