How to Choose the Right Oil Diffuser

The right oil diffuser will help you truly enjoy the benefits of aromatherapy. Even if you’re not interested in the therapeutic benefits of essential oils, diffusers will make your home smell fresh and clean without forcing you to breathe in toxins (according to Huffington Post, scented candles are loaded with synthetic chemicals).

Diffusers come in many shapes and sizes, and there are different types to choose from, too. I’ve always been partial to ultrasonic models, but you may find that you prefer something different.

Let’s take a closer look at the different types of diffusers available and some of the things I would recommend looking for when choosing a model.

Types of Oil Diffusers

There are four main types of diffusers on the market today:


Group of essential oil diffusers

Ultrasonic diffusers create a very fine mist, which disperses the essential oils into the air. The diffuser stimulates the oils by applying an electronic frequency from a metallic strip or disc immersed in water.

As the metal vibrates, it causes the top layer of oil and the water to disperse up into the air.

The nice thing about ultrasonic devices is that they use very little energy. Because there is no heat involved, it also helps preserve the beneficial properties of the essential oils. Virtually all of the oil gets dispersed into the air.

Watch the video below to see how ultrasonic diffusers work.

I prefer ultrasonic diffusers because they allow you to maximize the benefits of aromatherapy. It’s quiet, too, which makes it easy to relax and unwind while using it.


Heat diffusers are the most basic of oil diffusers. It uses the heat from a tea light candle to disperse the oil into the air. There are also electric models that use a lightbulb to heat the oil.

Many people love heat diffusers because they’re silent and they enjoy the light from the candle. I personally stay away from this type of diffuser because the heat can change the chemical composition of the oil.

If you want to go the heat diffuser route, I would recommend choosing one that keeps the heat source far from the oil.

While not my favorite option, I think heat diffusers are the best choice for small rooms because large quantities of oil aren’t dispersed into the air at one time. Dispersing too much oil into a small space can be overwhelming or may be harmful in some cases.


An evaporative diffuser works a little differently than other diffusers we’ve discussed. These models come equipped with a sponge, which you soak with oil. A fan inside of the unit disperses the oil into the air.

Evaporative diffusers are quiet, so they’re a great option for relaxing or even in spas.


Nebulizing diffusers are great for larger spaces because they disperse a lot of oils into the air in a short amount of time. I compare these diffusers to perfume sprayers – except they are controlled electronically.

There are benefits to this type of diffuser. Health blogger Wellness Mama prefers nebulizing diffusers when the family gets sick because they disperse a continuous stream of pure essential oils into the air.

Organic Aromas explains how nebulizing diffusers work, and their benefits.

These units usually have timers, so you can choose how long you want to diffuse. The only thing I don’t like about nebulizing diffusers is that you can go through bottles of essential oils quickly if you let it run continuously.

What to Consider When Choosing an Oil Diffuser

By now, you should have a pretty good idea of which type of diffuser you want for your home. But type isn’t the only thing to consider. There are some other things that I would recommend considering when choosing a model.

Oil Capacity

How much oil can the diffuser hold? For ultrasonic and evaporative models, this may not be much of a concern. But with an ultrasonic diffuser, you want to consider how much water the unit can hold. The more water, the more oil you can add.

If you plan to buy a heat diffuser, then you need to consider the size of the oil bowl. The larger the bowl, the more oil it can hold.

Capacity may not be an issue if you use the diffuser in a smaller room. I’ve found that just a few drops of oil is more than enough for a bedroom or living room area.

The Prairie Homestead recommends  only using a few drops of each oil in their recipes.

For larger spaces, you will need a larger capacity, especially with large groups of people.

Safety Features and Automatic Shut-Off

Group of colorful essential oil diffuser

Diffusers with automatic shut-off features are ideal because they allow you to set-it-and-forget-it. I almost always wind up falling alseep during my aromatherapy sessions, and sometimes, I like to use my diffuser to help me fall asleep. Having an automatic shut-off feature means I can fall asleep without worry that something will overheat or break.

Easy Cleaning and Oil Changing

Cleaning is another important aspect to consider. Look for models that are easy to clean and maintain.

Heat and ultrasonic diffusers are, in my opinion, the easiest to clean. But you do have to remember to change the water frequently when using an ultrasonic device.

One of the most popular essential oil companies, doTERRA offers some great tips on cleaning diffusers.

Clean-up with a nebulizing diffuser is almost non-existent, so this may be a good option for you if you don’t want any clean-up at all.