Best Ultrasonic Humidifiers of 2021

Here’s why you should go the ultrasonic route.

If you spend a lot of time at home, you may sometimes notice your skin feeling a little dry. The air in your house typically lacks moisture, which is why your skin will be more prone to drying out indoors (1). You may even find your eyes and nose become irritated too.

If this is the case, then you may need a humidifier. In this article, we’ll be talking about the five best ultrasonic humidifiers available right now. So, wave goodbye to dry skin caused by the air in your home.

Our Top Picks

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Compare the Best
Product Image of the LEVOIT Humidifiers for Large Room Bedroom (6L), Warm and Cool Mist Ultrasonic Air Vaporizer for Home Whole House Babies, Customized Humidity, Remote Control, Whisper-Quiet, White
Best Overall
Levoit LV600HH Hybrid Ultrasonic
  • High mist output
  • Warm & cool mist settings
  • Long runtime
Product Image of the GENIANI Top Fill Cool Mist Humidifiers for Bedroom & Essential Oil Diffuser - Smart Aroma Ultrasonic Humidifier for Home, Baby, Large Room with Auto Shut Off, 4L (White, 4L)
Best Small Humidifier
Geniani Top Fill Cool Mist
  • Smart mode
  • Easy-access control
  • Easy refill
Product Image of the Pure Guardian H4750AR Ultrasonic Cool Mist Humidifier, 120 Hrs. Run Time, 2 Gal. Tank Capacity, 600 Sq. Ft. Coverage, Large Rooms, Quiet, Silver Clean Treated Tank, Essential Oil Tray
Best Large Humidifier
Pure Guardian H4750AR Cool Mist
  • Silver clean tank
  • Long runtime
  • Auto shutoff
Product Image of the GENIANI Top Fill Cool Mist Humidifiers for Bedroom & Essential Oil Diffuser - Smart Aroma Ultrasonic Humidifier for Home, Baby, Large Room with Auto Shut Off, 4L (White, 3L Classic)
Best Budget Humidifier
Geniani Cool Mist Humidifier
  • Night light feature
  • Silent operation
  • 2-year warranty
Product Image of the VOGVIGO Humidifiers Large Room, 5.5L Warm and Cool Mist Ultrasonic Humidifiers for Bedroom Baby , Customized Humidity Vaporizer Quiet Air Humidifier with LED Touch Display and Remote for Wholehouse
Best Spa Pick
Vogvigo Large Room Humidifier
  • Larger machine
  • Aroma box
  • LED touch display

Types of Humidifiers

If you’re a novice to these gadgets, let’s first talk about the different types of humidifiers.


An evaporative humidifier produces moisture by sucking in air from the surrounding environment — via fan — and moving that air over a wick. The wick is moist, and the water vapor generated is released back out into the air.


Ultrasonic humidifiers contain built-in tanks or reservoirs, and water vapor is released from these through rapid vibration. The inaudible vibrations create this vapor by breaking down water particles.

Nowadays, ultrasonic humidifiers have become the most popular option. One of the main reasons for this is the noise or lack thereof. Ultrasonic humidifiers are easily the quietest of all humidifier types.

There is some controversy around ultrasonic humidifiers due to “white dust” (2). This forms because there are minerals in the tap water you are likely to use in your humidifier. We suggest reading up on this and being aware of the type of water you use in your machine.

How to Choose the Best Ultrasonic Humidifier

Every humidifier comes with a set of unique features. Consider these to pick the right one for your home:


This word may seem a bit mystifying at first but think of it this way. What does a thermostat do? It controls the temperature of a room. So a humidistat must control the humidity.

It’s important to get a humidifier with some form of humidistat. This will allow the machine to detect the humidity level of the room and adjust itself accordingly. If it doesn’t have this, you risk the humidifier creating too much moisture in the air.

In this case, you may end up with a bad case of mold or mildew growing all over your walls and ceilings. These aren’t just gross; they’re also bad for your health and particularly dangerous to vulnerable groups like children (3).

Low Noise

One ofthe reasons why ultrasonic humidifiers are so popular is that they produce so little noise. In fact, you can get models that are basically silent.

If you do want a version that makes noise — maybe you don’t mind the sound or just really like to know that it’s switched on? You also have that option. When you’re browsing humidifiers, take a close look at the specs or product description, and it should let you know.

Variety of Settings

You may think that there is simply one “good air moisture level” and that there isn’t really much adaptability between environments.

First,consider the different seasons. Humidity is vastly different between summer and winter. You might be in a region where the humidity is crazy high at certain times of the year.

Secondly, options such as “dry skin” and “cold and allergy” are essential. These all call for different moisture levels to keep you comfortable. Your house might be more prone to dryness than others, and your allergies are definitely a concern.

When you’re shopping around, make sure the humidifier you’re looking at has a variety of pre-programmed settings. Otherwise, it may not be able to tackle your specific needs.

Area Coverage

All the rooms in your house are different sizes, as are people’s offices. Humidifiers are designed for rooms of all sizes — some can even cover up to 1,000 square feet! But, not every humidifier will be able to cover a large room.

If your room or space is small, you may want to consider a tabletop option.


Like a lot of machines, a humidifier needs to be cleaned. More unique to humidifiers is, they need to be refilled — how often this will be, depends on the size.

Humidifiers need regular cleaning— at least a basic rinse and dry. This is important as the inside of the machine is warm and moist, which is the perfect environment for bacteria to grow. So, you need a machine that you can access easily to clean properly.

These machines also come with different refill options, including bottom and top refill. A top refill is easier, as you don’t have to move the humidifier to do anything. This will depend on size, though, as not every humidifier can be a top refill.

The Best Ultrasonic Humidifier of 2021

You’ll find that there are many ultrasonic humidifiers online or in stores. If you’re struggling to narrow down your search, we’ve collected five of the best ultrasonic humidifiers.

1. Levoit LV600HH Hybrid Ultrasonic Humidifier

Best Overall Ultrasonic Humdifier

This first entry on our list should suit the majority of users. The Levoit LV600HH is a germ-free and whisper-quiet ultrasonic humidifier that offers both warm and cool mist settings.

The great thing about this humidifier is convenience. It has a low noise level, timer to switch itself off, remote control, and built-in sensor to detect humidity levels. The benefit of all of these features is that you won’t have to spend too much time fiddling with it yourself.

Those of you with larger homes will also want to consider this model. It can cover over 700 square feet. The design is sleek and modern, which should fit with the majority of decor.

Why We Love It

High Mist Output

If you’re looking to cover a larger space, this is a particularly attractive option. This humidifier provides a mist output of 500 milliliters an hour, meaning it can easily cover 753 square feet.

Warm and Cool Mist Settings

You will want different temperatures of mist depending on the time of year. This setting means you can get warm mist in the winter and cold mist in the summer. It’s way easier than having to buy more than one humidifier.

36 Hours of Use

Another big advantage of this humidifier is that it can run a pretty impressive 36 hours on the low mist setting.

Keep In Mind

Some Reports of Leakage

Customer feedback suggests this humidifier may have issues with leakage. We do want to stress, though, that this doesn’t appear to be a frequent issue and may be related to defective units. You should contact the manufacturer if it happens to you.

Additional Specs

Dimensions 11.3 x 7 x 10.5 inches
Capacity 6L/1.5 Gallon Capacity
Refill Type Bottom Filled
Use Time 36 hours on Low Mist Level
Additional Essential Oil Diffuser

2. Geniani Top Fill Cool Mist Humidifier

Best Small Ultrasonic Humidifier

Great things can come in little packages: say hello to the Geniani top fill cool mist humidifier. With a 4-liter capacity that covers 220 square feet, it may not be the humidifier for a large office, but it won’t let you down.

This machine has one of the most convenient filling options we’ve seen. The water is poured into the top rather than the bottom, and you don’t even need to remove the cap.

One of the benefits of this humidifier is that it offers a smart mode with an intelligent sensor that automatically adjusts moisturizing speed to match the environment.

If you want a humidifier for a small room or space, this is the best option for you.

Why We Love It

Smart Mode

We really can’t overstate how cool this smart mode is. You don’t have to pay attention to how your environment is changing because the built-in sensor does it all for you. It really puts this one on another level.

Easy-Access Control Button

Having a control button is important anyway, but it’s even better when you have a button you can easily reach. It’s right on the front!

Easy Refill

This is probably the easiest of the humidifiers to refill. It only takes a couple of minutes, and you don’t even have to remove the cap. Just pour the water straight into the top.

Keep In Mind

White Dust

We have seen some feedback that suggests this humidifier may generate more white dust than other options.

Additional Specs

Dimensions 12.4 x 9.3 x 6.6 Inches
Capacity 4 Liters
Refill Type Top Fill
Use Time 24 Hours on Low-Speed Mode
Additional Transparent Water Gauge

3. Pure Guardian H4750AR Cool Mist Humidifier

Best Large Ultrasonic Humidifier

Although not the largest option on our list, the Pure Guardian H4750AR cool mist humidifier is probably the best of the large options. It has a two-gallon capacity and can cover 600 square feet.

This compact humidifier is quiet, filter-free, and offers a huge 120-hour run time. It’s not as convenient as other options in terms of functionality. However, it has everything you could need without your having to pay a lot of extra money.

It also can generate both cool and warm mist, which is always a bonus in a humidifier.

Why We Love It

Silver Clean Tank

Humidifier tanks get dirty very easily, and you don’t want nasty gunk building up in yours. This model helps tackle the issue by providing silver clean protection, which helps prevent the build-up of mildew.

Long Continuous Use

This model has an impressive running time of 120 hours. This is thanks to the super big 2-gallon tank. That’s a great feature if you don’t want to be constantly checking up on your machine.

Auto Shutoff

Auto shutoff means that your humidifier will only run until your tank is empty, then it will turn itself off. This is as opposed to staying switched on but doing absolutely nothing: a great energy-saving feature.

Keep In Mind

Not the Easiest to Clean

We are reaching a little bit here, as this really is a product with virtually no downsides. The only minor thing we could say is that a lot of the humidifier’s parts can’t be removed or moved about, making deep cleaning a little difficult.

Additional Specs

Dimensions 7.75 x 15.03 x 12.48 Inches
Capacity 2 Gallons
Refill Type Top Fill
Use Time Up to 120 Hours
Additional Silver Clean Tank

4. Geniani Cool Mist Humidifier

Best Budget Ultrasonic Humidifier

The Geniani Cool Mist Humidifier will keep your room fresh for between 12 to 24 hours, depending on the setting.

This humidifier is the perfect example of how something being on the cheaper end doesn’t necessarily mean it lacks features or convenience.

In fact, this humidifier and its 3-liter tank produce a phenomenal amount of mist, enough to make your room or office feel like a tropical jungle.

Why We Love It

Night Light Feature

If you’re someone who can’t sleep in pure darkness, this humidifier offers you a night light. That should also work if you plan to put the ultrasonic humidifier in your kid’s room.

Silent Operation

This model operates in near-silence. In general, background machine noise can be annoying, but this is especially advantageous when you’re sleeping or trying to relax.

2-Year Warranty

Warranties can be a real lifesaver. Even when you buy a fantastic product, there’s always the most minor of chances that you might get a defective unit.

Keep In Mind

Slightly Fidgety to Refill

This is a bottom refill tank, as a few other models on the list are. There is a slight annoyance to this one, though — the top is round, which means you can’t balance it upside down. It’s not the biggest issue, but it’s not particularly convenient either.

Additional Specs

Dimensions 12.6 x 8.2 x 8.2 inches
Capacity 3L Capacity
Refill Type Bottom Refill
Use Time 24-Hour Continuous Use on Low Mist Setting
Additional 360-Degree Mist Nozzle

5. Vogvigo Large Room Humidifier

Best Spa Pick

The Vogvigo large room humidifier is one of the best models out there in terms of continuous operation. It runs for a whopping 40 hours.

This humidifier contains an ionic generator. This means it can soften hard water and is able to release both mist and steam vapors. That makes this option perfect if you have sinus problems or asthma, as the water is purified before being released.

The humidifier also has an essential oils option, so you can give yourself some sauna-quality aromatherapy.

This is one of the larger models available and could cover basically the size of a whole house.

Why We Love It

Larger Machine

This machine is perfect for large spaces. It can humidify a whopping 750 square feet, so it’s a great option if you’re looking for an office humidifier.

Aroma Box

In the realm of nifty features, this model has a really nice one — a little box that you can pour essential oils into. The humidifier will then pump a lovely smell into the air around your home. It’s like having your very own spa day.

LED Touch Display

Here are some big bonus points for convenience. Instead of lots of annoying buttons, you get to feel super modern with a fancy touch system. The screen can also turn off, so you won’t have to see it lit up in the dark.

Keep In Mind

Some Reports of Leaking

Some buyers report issues with leaking. Contact the manufacturer if you find this issue with your humidifier.

Additional Specs

Dimensions 14.5 x 12.5 x 10 Inches
Capacity 5.5L Capacity
Refill Type Bottom Refill
Use Time 40-Hour Continuous Use on Low Mist Setting
Additional LED Touch Display

Ultrasonic Humidifier Comparison Chart

Product Best Dimensions Capacity Refill Type Use Time Additional
Levoit LV600HH Hybrid Ultrasonic Overall Choice 11.3 x 7 x 10.5″ 6L/1.5 gal Bottom Filled 36 hours Essential Oil Diffuser
Geniani Top Fill Cool Mist Small 12.4 x 9.3 x 6.6″ 4 L Top Fill 24 Hours Transparent Water Gauge
Pure Guardian H4750AR Cool Mist Large 7.75 x 15.03 x 12.48″ 2 gal Top Fill 120 Hours Silver Clean Tank
Geniani Cool Mist Humidifier Budget 12.6 x 8.2 x 8.2″ 3L Bottom Refill 24 Hours 360-Degree Mist Nozzle
Vogvigo Large Room Humidifier Spa Pick 14.5 x 12.5 x 10″ 5.5L Bottom Refill 40 Hours LED Touch Display

What Makes an Ultrasonic Humidifier Different?

We’ve gone through the basics of how an ultrasonic humidifier works differently to an evaporative one; you may wonder if that really affects anything.

Let’s take a look at the benefits an ultrasonic humidifier gives you.


Some evaporative humidifiers utilize heat to generate the necessary water vapor to release into the air. This inherently has a level of danger due to the potential of overheating. Ultrasonic humidifiers, however, do not require any heat at all.

More Control

Ultrasonic humidifiers are generally the more modern and more technological option. The mechanism allows for more features and controls that can streamline the entire process. This includes features such as nightlights, automatic shutoff, automatic switching between settings, and switching between cool and warm mist.

Less Wastage

Overall, ultrasonic humidifiers consume less power. This means less wastage and more savings for you.

How Long Do Ultrasonic Humidifiers Last?

Ultrasonic humidifiers usually last around two to six years, depending on how well you maintain it. Lifespans vary for different brands and different sizes.

Make sure you clean your humidifier regularly to keep it running efficiently, and you’ll get your money’s worth.

Go Ultrasonic

If you have dry skin, the sniffles or allergies, and you’re sure the air in your house is a big factor behind it, then a humidifier is a really good idea. Or, if you simply want to have a more natural humidity balance in your environment.

On top of that, do you want a humidifier that’s safer and quieter – or even totally silent? Then the best ultrasonic humidifier is the choice for you.

Remember when you’re looking for an ultrasonic humidifier to consider the humidistat, size of the tank, noise level, and pre-programmed settings.

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About the Author

Matthew Sullivan

Matthew is a freelance writer with several years of experience in DIY and HVAC. For as long as he can remember, Matthew has always found great pleasure in taking things apart and learning how to put them back together.
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