The 4 best essential oil diffusers of 2024, tested and reviewed

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If you love filling your home with a signature scent, try using one of the best essential oil diffusers to spread consistent and natural fragrance as an alternative to the best candles. These diffusers safely and naturally spread fragrance without an open flame. 

A diffuser holds essential oils or fragrance oils and disperses them into the air. There are two main types of diffusers: ultrasonic and nebulizing. Ultrasonic diffusers use evaporating water to carry essential oils into the air, but nebulizing diffusers create an internal vacuum that lifts fragrance into the air, so there are no humidifying effects. The main difference between the two is that ultrasonic diffusers distribute a more diluted fragrance that lasts longer, and nebulizing diffusers deliver highly concentrated fragrance. 

To determine the best essential oil diffusers, we tested nine options for ease of use and how well they worked and consulted with Amanda Lattin, dean of aromatherapy at American College of Healthcare Science.  The Asakuki 500 mL Premium Essential Oil Diffuser is our top choice, with a large water tank that doesn't need to be constantly refilled, adjustable time and mist settings, and an easy-to-use design. Alternatively, the Pura 4 Smart Fragrance Diffuser is a plug-in waterless design that let you control fragrance intensity from its accompanying app. Pura uses its own scent vials, and partners with popular candle brands for its vast library of scents.

Read more about how Insider Reviews tests and research home products here.

Our picks for best essential oil diffusers

Best overall: Asakuki 500 mL Premium Essential Oil Diffuser - See at Amazon

Best compact: Urpower 2nd Generation Essential Oil Diffuser - See at Amazon

Best smart: Pura 4 Smart Fragrance Diffuser - See at Amazon

Best waterless: Organic Aromas Raindrop Nebulizing Diffuser - See at Amazon

Best overall

According to Lattin, an important feature to consider in an oil diffuser is a timer for a customized run time, and the Asakuki has just that. 

One of the standout features of the Asakuki model, which contributed to its position as the best overall essential oil diffuser, is the simple inclusion of a remote. It conveniently lets me set a timer, change the LED lighting, and control how soft or powerful I want the mist to be from wherever I'm sitting. 

The Asakuki also impressed with its large 500 mL water tank, which means you won't have to refill it frequently. In my testing, I ran it for a full 16 hours before needing to refill the reservoir. Another plus for this diffuser is how easy it is to clean with water and a few drops of white vinegar.

The Asakuki diffuses oils well in rooms of all sizes without being too overpowering. It filled up my 180-square-foot bedroom and my 220-square-foot living room, which has a 25-foot-high ceiling. 

The only downside of this diffuser is its 6.6-inch diameter. Most of the diffusers we tested are more slender. I recommend placing it on a wide surface such as a side table, desk, or counter. 

Best compact

The Urpower 2nd Generation Essential Oil Diffuser is small but mighty, and you get all of the benefits of an essential oil diffuser without spending a lot of money. If you're someone who doesn't care for fancy features, this 100-mL diffuser nicely saturates small rooms with essential oils. 

Despite having a smaller water capacity, the Urpower has a run time of six hours, which is longer than some diffusers we tested that have a larger reservoir. Although this diffuser isn't the fanciest, it has seven LED mood lights and automatically shuts off after its run time is complete.

The instructions don't specify how to clean the Urpower, but water and a few drops of white vinegar worked well for me.

Best smart

The Pura V4 Smart Fragrance Diffuser is a plug-in diffuser that works exclusively from the Pura app, which allows you to adjust the fragrance's intensity and set a schedule for when you want your Pura to diffuse. The app was super easy to use with detailed step-by-step instructions; connecting the Pura to my WiFi took less than a minute. The latest Pura 4 automatically detects which fragrance vial is inserted with an NFC chip and tracks usage and the remaining amount of fragrance.  

It's great not having to worry about cleaning this diffuser because it's completely waterless and uses heat to diffuse oils. You can choose from more than 100 fragrances, including partnerships with some of the best candle brands like Capri Blue, Otherland, LAFCO, and Nest NY. The downside is that the diffuser is only compatible with Pura's essential oils vials. If you aren't sure which fragrance to choose from, the company offers a fragrance quiz that will match you with a few scents based on your answers. The vials cost between $10 to $20, which is typically still less costly and longer lasting than a candle. Each vial should last up to 120 hours, depending on the intensity you put it at. Within the app, you can purchase refills and set up subscriptions too. 

For my tests, Pura sent four fragrance vials; my favorites being  Capri Blue Volcano and Otherland Cardamom Milk. With the Pura Diffuser's adjustable fragrance intensity, both scents diffused well across my open floor plan and vaulted ceilings.

Everyone in my house was amazed by how I could control this smart diffuser from anywhere, even outside the house. I loved turning it on when I had guests over to welcome them with a great-smelling space. With its ease of use, convenient app features, LED color wheel lighting, and amazing fragrances, this is by far the best smart diffuser.

Best waterless

Nebulizing diffusers solely diffuse essential oils. With ultrasonic diffusers, "essential oils just sit on top of the water, so the diffuser is making it to where droplets of water are coming out, and there are little bits of essential oils riding on those droplets of water," said Lattin. With a nebulizer, a stream of pressurized air hits the essential oil, and it is ultimately released into the air as a mist of very small particles. This more complicated design makes them more of an investment.

With the Organic Aromas Raindrop Nebulizing Diffuser being my first waterless diffuser, I didn't know what to expect. Lattin says a few drops of essential oil in a nebulizing diffuser goes a long way. Although the brand recommends adding 20 to 25 drops, I took Lattin's advice and added four drops of essential oil inside the glass reservoir. 

Even though Organic Aromas says its diffuser can cover up to an 800-square-foot room, I raised the intensity level just a bit, and within seconds, I could smell the essential oils throughout my entire 2,924-square-foot home. This waterless diffuser has a two-hour run time, but given how strongly it dispenses oils, this is more than sufficient time. Plus, I could still smell the fragrance lingering once the diffuser automatically shut off. 

Cleaning the Raindrop Nebulizing Diffuser was simple but took some time due to how strong the oils are. I removed the glass pieces, placed them into a bowl of hot water and dish soap, and repeated this process until I couldn't smell the essential oils as strongly. Once the pieces finished soaking, I rinsed them off with water and let them completely air dry before reassembling. 

What to look for in a fragrance diffuser

When it comes to essential oil diffusers, there are three types of dispersing methods as well as several important features you should know about.

• Ultrasonic diffusers use a high-frequency vibration to disperse an oil and water mixture. They are a good choice for enclosed areas with low humidity, acting as both humidifiers and oil diffusers.
• Nebulizing diffusers require no heat or water and disperse just essential oils. They produce a more potent scent but use much more oil than other types of diffusers.
• Evaporative diffusers don't use water, and essential oils are placed on a filter and circulated by a fan. 

Once you've settled on a diffusing method, the choices are nearly endless when it comes to features like settings, coverage area, and aesthetic appeal. Some things to consider before you make a purchase:

• Automatic shutoff: This feature prevents damage if an ultrasonic diffuser runs dry.
• Lighting: Many models have an LED light feature. Read carefully to determine the color of the light and whether it can be manually controlled if you don't want it on all the time.
• Intensity: Are the diffuser settings continuous, intermittent, or both? Nebulizing diffusers produce a stronger output than other models.
• Capacity and coverage: If you choose an ultrasonic diffuser, the water capacity can range from 3 to 32 ounces. The larger the capacity, the more square footage it will cover. 
• Timers: A timer can help you control short or continuous runs and prevent damage if the diffuser is accidentally left on too long.

How we tested essential oil diffusers

When testing each of the picks for the best essential oil diffusers, I ran each one in different size rooms over a span of two months. I observed how well they diffused oil, their ease of use and cleaning, and their water capacity. I also interviewed Amanda Lattin, dean of aromatherapy at American College of Healthcare Science, about essential oils and diffusers.  

Below are the criteria we used to determine the best essential oil diffusers. 

Ease of use: After unboxing the diffusers, I made a note of how easy or difficult it was to set up each one. For the app-enabled smart diffusers, I noted how quickly I was able to connect the diffuser to WiFi and my phone along with how user-friendly the app was. Most diffusers require water and a few drops of essential oil and will start up with a click of a button. For ones that require more steps, I considered whether their performance outweighed the extra effort.

Ease of cleaning: Along with ease of use, I made note of how tedious or simple it was to clean each diffuser. 

Run time and water capacity: I filled each diffuser to its maximum water capacity and noted how many hours it diffused the oils and how often I had to refill the diffuser. For nebulizing diffusers, I considered how much time was needed to diffuse oils throughout a room.

Strength of essential oils in each diffuser: I kept track of how many drops of essential oils I added to each diffuser based on its recommended amount and noted how strongly the fragrance dispersed from each diffuser. I also observed how long the oil's scent lasted in the room once the diffuser stopped running.

Square footage covered: To test the strength of each diffuser, I ran each diffuser in my 180-square-foot bedroom; 220-square-foot living room, which has a 25-foot-high ceiling; and my 200-square-foot office. 

Essential oil diffuser FAQs

What are essential oils?

According to Lattin, essential oils are extracted from a specific part of a plant, such as the flowers, seeds, roots, peel, bark, or leaves. Genuine essential oils "have information about where the essential oil was produced" and when it was made Lattin said. Often, manufacturers will link to analysis reports of their essential oils.

How do you clean an essential oil diffuser?

In order to get the most out of your device, it is important to learn how to clean your essential oil diffuser. 

After using your diffuser, it's important to clean the device regularly to avoid any erosion of the plastic parts. Most of the diffusers I tested included directions to clean the reservoirs with white vinegar, water, and dish soap after one or two uses. 

Are essential oils harmful to babies and children?

John Hopkins All Children's Hospital recommends taking precautions when using essential oils around children but notes that they may have some benefits. Never apply concentrated essential oils directly on a child's skin, and store them securely out of reach. Peppermint oil may cause seizures in children under 30 months old. Read labels closely to ensure you are using pure oils rather than synthetic formulas.

Are essential oils harmful to pets?

According to the ASPCA Animal Poison Control Center (APCC), concentrated essential oils can be dangerous to pets, whether they consume them or their skin comes into contact with them. The APCC recommends only using the diffuser for a short period of time and not using one if you have birds due to their sensitive respiratory tracts.

Where should I put an essential oil diffuser in a room?

While you want the diffuser to be in a spot with good airflow, it should also be inaccessible to pets and children. You'll also want to make sure any vapor can dissipate without coming into contact with delicate surfaces or electronics. 

What are the benefits of essential oil diffusers?

Incorporating diffusing into your daily routine has been shown to reduce stress, promote healthy sleeping habits, and reduce inflammation. 

Before you start diffusing, it's important to know that you can overdo it. "You can end up inhaling too much or interacting with it too much if it diffuses all day or all night, which can cause irritation," says Lattin. "You'll want to start out by diffusing for short periods of time during the day to see how well you tolerate it, and setting up your diffuser in an area that isn't too close."

What essential oils are good for sleep?

While buying essential oils can be a personal experience, lavender, chamomile, and peppermint are three oils that help when winding down in the evening. 

Lavender oil benefits include calming nerves and reducing inflammation. Because of this, lavender aromatherapy is widely used in sleep products and is often the primary oil used in premade essential oil sleep blends.

Like a warm cup of chamomile tea, chamomile oils are shown to promote relaxation and drowsiness. Lastly, if you are having trouble falling asleep due to a stuffy nose or upset stomach, peppermint oil benefits include reducing pain and helping aid digestion.