Levoit Classic 300S Ultrasonic Smart Humidifier review

If the humidity in your home is too low, dry air can contribute to many health issues. You can alleviate symptoms such as dry skin and irritated sinuses by using a humidifier, but it can be tricky to maintain your home’s ideal humidity level without micromanaging the device.

The Levoit Classic 300S Ultrasonic Smart Humidifier can automatically adjust its misting levels to maintain your desired humidity. It also boasts helpful features such as app control, a nightlight and a tray for adding essential oils.

We wanted to see if the Levoit Classic 300S Ultrasonic Smart Humidifier could keep a room comfortable without requiring constant adjustment, so we put it to the test. Here’s what we learned.

Testing the Levoit Classic 300S Ultrasonic Smart Humidifier

Our testers had never used a humidifier before, but they were interested in getting one to make their home more comfortable in drier months. Despite their lack of previous knowledge, they found the Levoit Classic 300S very intuitive. 

What is the Levoit Classic 300S Ultrasonic Smart Humidifier?

As an ultrasonic humidifier, the Levoit Classic 300S contains a metal diaphragm that vibrates at ultrasonic speeds to generate a cool mist of microscopic water droplets without a lot of noise.

The humidifier pairs with the VeSync app and Alexa or Google Assistant for hands-free control and customizable settings. Plus, the Levoit Classic 300S can automatically start up or shut down by detecting the humidity levels in your home.

It also features a night-light and a tray for diffusing essential oils. Its tank holds enough water to run up to 60 hours before needing a refill.

Levoit Classic 300S Ultrasonic Smart Humidifier price and where to buy

The Levoit Classic 300S Ultrasonic Smart Humidifier costs $79.99 and is available at Amazon and Home Depot. It comes with a six-liter tank, three essential oil trays, an extra water filter and a cleaning brush. Additional replacement filters are sold separately.

How to use the Levoit Classic 300S Ultrasonic Smart Humidifier

To get started with the Levoit Classic 300S, fill the top-fill six-liter tank with distilled or filtered water. Using filtered water, especially if you live in an area with hard water, can prevent mineral buildup in the device as well as white dust on your belongings.

Once the tank is full, use the controls on the humidifier’s front to set your target humidity. The Levoit Classic 300S weighs less than 5 pounds empty, so it’s relatively easy to move around as needed.

If you want to add essential oils to the humidifier, Levoit recommends adding approximately 10 drops to the aroma pad. Don’t add essential oils directly into the water tank or the misting mechanism can be damaged.

To prevent the growth of mold and bacteria, it’s vital to empty the humidifier’s tank and let it dry out after each use. Regularly replacing the filters will also help keep the Levoit Classic 300S clean and safe.

Levoit Classic 300S Ultrasonic Smart Humidifier benefits

The Levoit Classic 300S features a sleek and modern design. It’s a significant step up from the models we remember from childhood. In the small rooms of the house where we tested, the Levoit Classic 300S ran nearly silently and took quick and accurate readings of the room’s humidity.

Since it can monitor the humidity in the room, the Levoit Classic 300S shut itself off once the right humidity level was reached, so it didn’t coat everything in the room with moisture. Its tank was easy to empty and refill.

The Levoit Classic 300S’s self-regulating features worked very well. We tested them by trying to run the humidifier on an already-humid day and the Levoit Classic 300S shut itself down almost immediately. We appreciated the app connectivity, but our testers found the Levoit Classic 300S easy to use even without those added features.

Levoit Classic 300S Ultrasonic Smart Humidifier drawbacks

As with most humidifiers, the Levoit Classic 300S needs some distance from any walls, which can sometimes make finding a good place for it tricky. Depending on your room size and desired humidity level, this Levoit model may need to be refilled more frequently than the stated time frame. It also has some nooks and crannies that can be challenging to clean.

Some users report issues with app functionality on Android, and some crucial settings, such as the automatic humidity level setting, are only available through the app. While the aroma trays are easy to use, some users would have preferred a stronger scent from the Levoit Classic 300S.

Should you get the Levoit Classic 300S Ultrasonic Smart Humidifier?

Levoit Classic 300S Ultrasonic Smart Humidifier

Despite its high-tech appearance and features, the Levoit Classic 300S Ultrasonic Smart Humidifier is easy to use no matter how comfortable you are with technology. Its precise humidity readings would make it a great pick for someone whose health issues are mitigated by humidity or for anyone who appreciates the degree of precision and control offered by smart appliances.

Consider other products

Honeywell Designer Series Cool Mist Humidifier

Honeywell Designer Series Cool Mist Humidifier

This similarly priced humidifier offers similar features to the Levoit, such as a generous water tank and essential oil feature, but it requires no filters so there are no recurring costs. However, having no filters means it needs to be cleaned more frequently. 

Sold by Amazon

Crane Cool Mist Humidifier

Crane Cool Mist Humidifier

Also featuring ultrasonic mist and a large top-fill tank, this humidifier boasts dishwasher-safe parts and can diffuse essential oils. It even has a night-light that changes colors. However, it only lasts about 24 hours before needing a refill. 

Sold by Amazon and Home Depot

Pure Enrichment MistAire Cool Mist Humidifier

Pure Enrichment MistAire Cool Mist Humidifier

This tabletop humidifier is compact and lightweight while still effectively adding moisture to the air for up to 25 hours. It can’t dispense essential oils, but it does have a night-light. 

Sold by Amazon and Kohl’s 

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Laura Duerr writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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