The Best Essential Oil Diffusers

With more than 60 hours spent researching and testing top products on the market, we concluded that the Smiley Daisy – Hibiscus is the best essential oil diffuser available. We tested four new diffusers for this 2021 update and have added the Porseme 3D as another excellent choice. Its esthetic beauty alone is only one reason why this diffuser should be in your home. We also like the InnoGear diffuser, which is great for larger spaces.

Table of Contents

• The 13 essential oil diffusers we tested
• 1. Top pick: Smiley Daisy – Hibiscus
• 2. Also great: Porseme 3D
• 3. Best for large spaces: Innogear
• How we selected
• How we tested
• Important features to consider
• The bottom line

The 13 essential oil diffusers we tested

1. Top pick: Smiley Daisy – Hibiscus

While all seven of the diffusers we tested do a good job of releasing essential oils into the air, the Smiley Daisy – Hibiscus was easily the best of the pack. The diffuser’s short stature, coupled with strong build quality and four sturdy rubber feet means that this diffuser won’t get knocked over very easily.

What makes the Hibiscus really stand out is the vapor output it produces, as well as the quality of that output. The water capacity of the Hibiscus diffuser is 350ml, which is more than double the capacity of most other diffusers we tested. With a maximum run time of between 6 and 7 hours, this translates to approximately 55ml of vapor per hour.

The diffuser also produced a strong stream of vapor, which could be seen as much as 20 inches from the table, or about 16 inches above the spout on the diffuser.

The large capacity and strong vapor stream of the Hibiscus made a noticeable difference during our testing. We found that there was a strong scent — about as strong as when the diffuser was on — for about 15 minutes after we turned the diffuser off. The scent remained quite noticeable until the 30-minute mark, and a lingering scent remained until almost an hour after turning the diffuser off.

Our Top Pick: Smiley Daisy - Hibiscus

A top performer across every category while still maintaining affordability, the Smiley Daisy is our pick for most people.

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Operation of the Hibiscus is simple as well. The instruction manual has very straightforward instructions, and using the product feels intuitive right away. There are two separate buttons on the front of the diffuser — one for turning the diffuser on or off (including a setting for a 2-hour timer), and a separate button for turning on and off the light.

The light itself offers seven different color options, which can either cycle or be locked onto one color. The light itself isn’t particularly bright, so it could serve as an effective night light without disrupting sleep. (Especially if you choose the red light, as we found out in our night-light research.)

Finally, the Hibiscus essential oil diffuser is quiet. In our office, which measures about 40 decibels with the doors and windows closed, the diffuser only generated 46.5 decibels of noise.

Smiley Daisy also offers a 180-day warranty, which ensures that, if you’re one of the unlucky few that get a defective product, you’ll be able to get a replacement at no cost and with no hassle.

Overall, the Smiley Daisy Hibiscus Essential Oil Diffuser offers impressive build quality and the best overall performance of the essential oil diffusers we tested. At a price point below $40, the diffuser is a great value as well.

Minor drawbacks

While the Hibiscus was our best pick, there were a couple of negatives about the product. The biggest potential problem is the large footprint of the diffuser. Unlike most diffusers, which utilize vertical space in their design (and particularly for their water reservoirs), the Hibiscus is short and wide, measuring 8.3 by 6.6 inches (and only 3.2 inches of vertical height).

In addition, the light generated is minimal, functioning more as a design element than an actual source of light. All that said, these negatives are very minor when compared to the overall package. We’ve been using the Hibiscus for three years now, and it’s still humming along cheerfully.

2. Also great: Porseme 3D

Without a doubt, the Porseme 3D is the most beautiful and esthetically pleasing essential oil diffuser we tested for this 2021 update. Porseme has several styles to choose from, and we selected one from the Aladdin series. The base is similar to other diffusers, but that’s where the similarities end.

The main body of the Porseme is a gorgeous hand-blown glass bottle that fits snugly on top of the base. At first glance, the bottle is opaque silver. But when the diffuser is turned on, the interior lights up to reveal a firework pattern that seems to burst outward. It has a range of changing colors, but the blue and purple are the most vibrant, especially at night when the entire bottle is aglow.

Runner-up: Porseme 3D

Not only is the Porseme 3D highly functional and whisper-quiet, it's also one of the most beautiful essential oil diffusers on the market today.

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The Porseme can be programmed for half an hour, and one, two, and three hours. It holds only 100 ml of water, but during our testing, the mist — which emanates from the bottle’s spout — held strong and steady for three hours. Also impressive was how quiet the Porseme is: No one should have any problem falling asleep when it’s running.

If we have any complaint with the Porseme, it’s the same for all of the new diffusers we tested. After three hours, the aroma of the essential oil — no matter how potent the oil (eucalyptus in this case) — dissipates. So if you want your diffuser to run all day, you’ll need to add a few more drops of oil to revitalize the mist’s aroma.

The Porseme is a little bit more expensive than other diffusers, but you’re paying for a quality product. Porseme has other glass-bottle shapes, and even lamps, that are worth checking out.

3. Best for large spaces: InnoGear

After three years of great performance from our top pick, we set out to find a diffuser that would fill a different role, but with similar strengths. The InnoGear – Premium 500ml Diffuser isn’t just great at spreading your favorite essence across a large space: It can also do so for up to 12 hours of run-time.

Our previous endurance pick, the PureSpa – Deluxe, relied on a low output rate to get long run times from its 120ml tank. The InnoGear makes no such compromises.

The InnoGear diffuser also has a distinctive look. Unlike the faux-wood or white plastic shells that are so common, this model features a metal screen that adds some contrast to the colored lighting options.

Best for Big Rooms: InnoGear - 500ml

InnoGear gives you all-day run time and good reach throughout a larger space. This diffuser is a unique new look from a company with a great track record.

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This design doesn’t solve all of our reservations about the Smiley Daisy. If you’re looking for a compact diffuser to keep at a desk or on a small side-table, this is even less ideal than our top pick.

One other tiny flaw is noise: this is on the louder end of the lineup we’ve tested. There’s a small fan inside helping spread your favorite scent to all corners of a room, and that makes it just a hair louder than ultra-quiet models like the dōTERRA – Petal. It’s not going to be distracting during the day in a large room, but if you can’t sleep next to devices that make quiet, constant sounds this isn’t the best choice.

4. dōTERRA – Petal Diffuser

The dōTERRA – Petal Diffuser is another very strong option from our list of finalists. The materials feel strong and sturdy, and we expect that the Petal diffuser will stand the test of time.

During our testing, we also found that the Petal diffuser was able to reach the other side of our 8-foot conference table very quickly — the average our testers agreed upon was just 35 seconds. This is less than half the time that the Hibiscus diffused, and while not a particularly scientific testing method, it does say something significant about the dōTERRA diffuser’s ability to permeate a room quickly.

The light produced by the diffuser is a pleasant, soft white, and provides notably more light than the Hibiscus. However, the Petal diffuser is limited to only white light, as opposed to the wide range of color options offered by our top picks.

The Petal diffuser is very quiet as well. In our conference room, where ambient noise registered at 40 decibels, the Petal diffuser only generated 46 decibels when our noise meter was less than an inch away — comparable to the Hibiscus.

Similarly, the scent was quite noticeable for nearly 30 minutes after shutting off the diffuser (just like the Hibiscus), and the essential oil could still be smelled for about one hour after the diffuser was shut off.

Operation of the diffuser is simple. There are two buttons on the front, one for the light and the other for turning the diffuser on or off. One interesting feature we noticed was that the Petal Diffuser must have water in it before being turned on — however, we consider this a safety feature that we are better off having.

Another strange feature we noticed was that the diffuser defaults to a 2-hour timer, and hitting the button again then cycles through the 1 and 4-hour settings before shutting off again. This is a minor quirk, but it did stand out to us during testing.

There were a few areas in which it fell short of our top pick. First off, the Petal diffuser produces less vapor and has a smaller capacity than our top picks. The Hibiscus runs for around seven hours, and the InnoGear can pump out approximately 45 ml per hour for ten hours. The Petal’s four-hour maximum runtime and its high price make it harder to recommend when you look at the competition.

The bottom line is that the dōTERRA – Petal is a great product, and is more compact than the Hibiscus. However, in an apples-to-apples comparison, the Hibiscus is a better buy.

5. PureSpa – Deluxe

The Pure Enrichment – PureSpa Deluxe is a great product, and if we hadn’t also tested so many other great diffusers, we would have been confident recommending it as our best pick.

The PureSpa Deluxe has a 2-year manufacturer warranty that provides peace of mind, and we like the clean and polished design (despite the overly bold logo).

What makes the PureSpa Deluxe really stand out is its 8 to 10-hour running time, one of the longest we found. This means you can turn the diffuser on at the beginning of your workday (or before going to sleep) and it will run consistently throughout the entire day (or night) without a second thought.

The lighting is also well-executed, with the option to cycle through blue, green, red, yellow, and purple — however, there is not a setting to stay locked onto one color. Also, much like our top picks, the PureSpa Deluxe did not become hot anywhere, even after running continuously for 30 minutes.

Despite the positive features of the PureSpa Deluxe, there are a few problems that we couldn’t overlook, particularly when compared to the Smiley Daisy – Hibiscus and the dōTERRA Petal Diffuser:

First off, the water capacity of the PureSpa Deluxe is just 120ml, less than both the Hibiscus (350ml) and the Petal (150ml). That, coupled with the extended runtime of the PureSpa Deluxe means that the amount of vapor produced per hour is significantly lower than either of our top picks.

We calculated the vapor diffused by the PureSpa Deluxe per hour was around 12ml to 15ml. This stands in stark contrast to the Hibiscus (55ml per hour) and the Petal (37.5ml per hour).

This difference was noticeable in our testing as well. After 30 minutes with the PureSpa Deluxe on, we found that the scent in the room was certainly present, but notably weaker than it was with either the Hibiscus or the Petal diffusers. Furthermore, the scent was all but gone 15 minutes after turning the diffuser off.

Finally, the PureSpa Deluxe is notably louder than both the Hibiscus and the Petal diffusers. Our noise meter detected 51 decibels, which is about 5 decibels louder than both of our top picks.

Ultimately, the PureSpa Deluxe is worth considering if you want a diffuser that can run all day without needing to be refilled, and if you are more interested in having a subtle scent of essential oil in a particular room.

6. Asakuki

With a 500 ml capacity, the Asakuki was the largest diffuser we tested for this 2021 update. Visually imposing, the large plastic dome is not terribly attractive, so wherever you place the Asakuki, it will hardly pass notice. The Asakuki did produce a strong, steady mist that filled the air with the essential oil’s aroma in a couple of minutes, and its spout is on the side, so you can adjust the direction of the mist.

But as with other diffusers, the aroma completely dissipated after two hours. The Asakuki can be programmed for three time settings and high/low mist levels, but we found its buttons for controlling them unnecessarily confusing. This was not a quiet diffuser at all: A low hum persisted throughout as did the plip-plip of the water dripping inside. The Asukuki is reasonably priced, but we still prefer the Innogear for scenting a larger space.

7. Renwer

Another attractive diffuser we tested for 2021 is the Renwer 300 ml diffuser. Physically it’s pretty much the same as others: plastic container on top of a base. But it has a lovely metal casing that depicts a sprawling tree, and it would make a nice addition to any room. Its power plug is recessed, and an indentation for the power cord keeps the diffuser flat on the surface where you place it.

Like other diffusers, its internal light cycles through colors, but what’s different with the Renwer is that the colors increase and decrease in intensity, somewhat simulating sunrise and sunset. It produced a strong mist that diffused the scent quickly, but the aroma nearly vanished after one hour of run time.

Finally, the most frustrating feature is its programming, which is so complicated, we had to follow the instructions several times to figure it out. If it’s late at night, and you’re sleepily trying to adjust the Renwer or even just turn it off, you don’t want to be fumbling for the manual to perform a simple function.

8. Innogear USB Car Diffuser

A nifty idea that we wished had performed better is the Innogear USB Car Diffuser. Not only is it one of the only USB-powered diffusers on the market, but it was also specifically designed to fit snugly into a car’s cupholder.  The Innogear has a meager 50 ml capacity, but it’s decently designed so that the mist lasts for at least two hours; perfect if you have a long commute or are traveling. Since it emits mist at only 15 ml per hour, the mist stream is small and the scent can only be detected by the driver.

It has a generous two-foot power cord, and we were surprised that other than a slight dripping sound, the Innogear was quiet. The Innogear cycles through colors, but it’s pointless because you can’t see them when the diffuser is in the cupholder. However, if you’d like a little personal misting while working, you could keep the Innogear next to your laptop.

9. ZAQ Allay LiteMist Diffuser

The ZAQ Allay diffuser has one of the more creative designs of the diffusers we came across. The LED lighting looks great emanating from the long cap (which itself is available in multiple colors).

However, the diffuser itself only has a water capacity of 80ml, which with a maximum 4-hour runtime means that this diffuser only produces about 20ml of vapor per hour.

In addition, we noticed that the mist fell to the table — which indicates that this particular diffuser does not break the water into small enough particles to float through the room. This observation was supported by the fact that it took 2 minutes and 15 seconds for the scent of the essential oil to reach the other side of our 8-foot conference table.

Finally, the build quality of this diffuser, while not terrible, can’t really compete with several of the other products we tested. For the $40 price point, there are simply better options available.

10. iHeoco

(Editor’s note: The Nestar we reviewed has been rebranded as iHeoco, and we have changed references throughout.)

We picked up the iHeoco ceramic essential oil diffuser because of its compact size, clean lines, and affordable price. The tank is slightly larger than the similar Smiley Daisy – Love in a Mist diffuser below, and the rated maximum room size is bigger. The light only shines white.

While we like the look and the features on offer with this model, it just didn’t quite live up to the performance expectations we had after testing larger diffusers. It’s quicker to diffuse scents in an eight-foot-long room than many of the smaller models we tested, but it’s no competition for the dōTERRA.

This is smaller than our top pick, but it’s also a little bit more wobbly. For some people, that might be fine; it’s not going to fall over by itself. But for cramped quarters like a college dorm room or an essential-oil-friendly workplace, we’d prefer to give up a few square inches of desk space in return for the certainty that you’re not going to spill scented water everywhere.

11. Smiley Daisy – Love in a Mist

The intricate shapes etched into the porcelain make the Love in a Mist diffuser arguably the prettiest product we tested. The build quality of this diffuser is fantastic inside and out, with high-quality plastic for the interior reservoir. The Love in a Mist diffuser also has several lighting color options, which can cycle or remain locked.

However, during our testing, it took 3 minutes and 15 seconds for the scent of the essential oil to reach the other side of the table — significantly longer than our best picks. Unfortunately, we detected 52 decibels of noise next to the diffuser, notably louder than our best picks.

While this is a beautiful diffuser, it is more expensive than the other products we tested (around $60) with less impressive results. However, if you are more concerned with beauty rather than peak performance, this is a compelling (and reasonably functional) option.

12. Greenair Spa Vapor+

The Greenair Spa Vapor+ was the last diffuser we originally tested, and overall it is a decent product. With a 150ml tank and a 4-hour run time, this diffuser generates an impressive 37.5ml of vapor per hour.

However, this diffuser is on the noisier side, registering 52 decibels, and the scent of the essential oil disappeared soon after we turned off the diffuser (within 10 to 15 minutes). This fact, in conjunction with the considerable vapor production, signifies that the Spa Vapor+ is simply unable to produce vapor particles small enough to remain suspended in the air for extended periods of time.

13. PureSpa Compact Diffuser (Discontinued)

Before being discontinued, the PureSpa Compact diffuser was one of the most popular options on the market, with thousands of Amazon reviews averaging 4.6 stars. This diffuser is simple, easy to operate, and provides 7 hours of diffusing with 100ml of water. This diffuser also has ambient LED lighting and is made from cheap, but durable materials.

The most significant downside to this diffuser is the 100ml tank and a 7-hour run time — which translates to a paltry 14.3ml of vapor per hour. This deficiency presented itself in the 2 minutes and 30 seconds it took for the scent of the essential oil to reach the other side of the table.

How we selected

We spent more than 40 hours researching essential oil diffusers in order to find the best products to test. We started by looking at the biggest brands in the category (such as dōTERRA), then expanded our search through subreddits like r/aromatherapy and r/essentialoils.

We also read through several essential oil and aromatherapy internet forums, read studies and articles about the benefits of essential oils and diffusing those oils, and read about the diffusers that industry experts recommended.

Once we knew what to look for, we narrowed our search with a few more criteria. Each diffuser needed to meet the following requirements:

• Have an automatic shutoff feature
• Operate for at least 4 hours
• Have a water capacity of 120ml or more
• Come with a trustworthy manufacturer’s warranty

From there, we factored in positive reviews on Amazon and by professional reviewers as well as several interviews with brand representatives to determine which products we should test in-house.

In 2019, we looked for updated products that would fill a larger room and run for a longer time. We’re still happy with our 2016 top pick for most situations, but we found a new runner-up that will run even longer and added some style options for people who don’t like fake woodgrain.

How we tested

In order to determine the best aromatherapy diffuser on the market, we ordered our seven finalists and put them through a series of tests in our San Diego office.

The first thing we did was open the box and read the instruction manual.

Next, we looked at the pieces and assessed how easy it would be to set up the diffuser. We also took into consideration the build quality of the diffuser.

After that, we looked at the settings and options available on the diffuser, including auto-off, lighting, timers, etc. We also took note of how intuitive the controls were, and whether we needed to actually refer to the instruction manual more than once.

We also checked to confirm that the specs and features listed on each diffuser’s product page matched the product itself. Specifically, we checked ambient lighting, operating time, water capacity, timers, and automatic shutoff when the water reservoir is depleted. Fortunately, all seven finalists held up to expectations, so we moved on to differentiating between their diffusing performance.

Diffuser performance metrics

To test each of the diffusers, we closed the doors and windows in our conference room, which measures 21 by 10 by 12 feet, for a total of 2520 cubic feet and 210 square feet.

We then filled the first diffuser with water and the recommended number of drops of essential oil (we used sweet orange oil for our testing because it has a distinct and easily detectable scent), making sure to use the same ratio of water to oil for each diffuser.

With the conference room closed off, we put the first diffuser at one end of our 8-foot conference table and calculated how long it took for the scent of the sweet orange oil to reach the other side of the table — with three judges to ensure as accurate a measurement as possible.

The notable performers in this test were the dōTERRA and PureSpa – Deluxe, both moving the scent quickly through the room. This doesn’t seem correlated to having a more diffuse plume of vapor or a faster (and thus louder) fan.

Quickest Diffusion: dōTERRA - Petal Diffuser

In our tests, the Petal consistently filled our office most quickly with the scent we were waiting for. Like the Innogear, This is a diffuser that really lives up to its room-size rating of 300 square feet.

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On the other end of the scale, PureSpa’s Compact model put out so little vapor that it took eight minutes to reach the other side of the room.

After measuring how long it took for the scent to reach the other side of the conference table, we left the room and let the diffuser run for 30 minutes with the doors and windows closed. We went into the room and touched the diffuser to determine if any parts were warm, and also used a decibel meter to measure the noise level from an inch away.

Note that the main sound coming from a diffuser is, in most cases, bubbling water. The models with the loudest noise level, like the Greenair and InnoGear, also have a small fan to help the vapor spread through your room.

Important features to consider

There are a lot of essential oil diffusers available online. In fact, there are more than 32,000 essential oil diffusers available on Amazon alone. With so many products to choose from, narrowing the field to a few finalists can feel overwhelming. That’s why it’s important to filter for only the best quality and best value diffusers.

First, determine the size of the room you want your diffuser to cover. Most (high-quality) diffusers list the size of a room in which they can effectively diffuse.

“Too much” diffusing is not a common problem with essential oil diffusers, especially since many offer a way to reduce output if necessary.

It’s also important to look at the water capacity of a diffuser, along with the estimated operating time. The operating time informs you of how long you can expect the essential oil scent to last in the room, while you can estimate the amount of water (and oil) diffused by taking the water capacity and dividing it by the operating time (e.g. 100ml and 2 hours would mean 50ml diffused per hour).

It’s also important to take into consideration the build quality of the diffuser you buy. Essential oils can be corrosive to some plastics, which means that a cheaply-made diffuser might break down after only a few months of use. All high-quality diffusers use polypropylene, or another strengthened polymer or material, to ensure the longevity of the product.

Ease of use is another important consideration. This includes both the setup (which should involve little more than putting water and your preferred essential oil into the diffuser) and clean-up.

The size, or dimensions of a diffuser might not matter to everyone. However, for those with limited space, it might be worth looking into a diffuser with a smaller footprint. Similarly, a noisy diffuser can be distracting in an otherwise-quiet setting — such as a yoga studio or even your bedroom.

Features such as a timer and ambient lighting can be a nice touch and are worth taking into consideration when comparing one diffuser to another.

Long-term testing notes

After years of almost daily use, both the Smiley Daisy Hibiscus and the dōTERRA Petal diffusers are still working very well. One thing we noticed with the Hibiscus, in particular, was that the residual smell of essential oils builds up in the reservoir over time. This doesn’t have a huge impact but can have an undesirable effect on some scents.

We were able to successfully remove the residual scents by cleaning the reservoir with a little dish soap, some warm water, and very light scrubbing with a paper towel. We don’t recommend using any cleaning products beyond dish soap or vinegar and make sure you triple-rinse the diffuser before using it after cleaning. Remember that everything that’s in the tank will go into your room air and lungs.

The bottom line

All of the diffusers we tested can generate enough vapor to make a small to mid-sized room smell like the essential oil of your choice. However, some did better than others, especially when the price is taken into account.

The Smiley Daisy – Hibiscus stole the show, generating lots of vapor and producing a long-lasting scent in our conference room. The Hibiscus also has excellent build quality, and its low center of gravity makes it a sturdy fixture on any flat surface.

The Porseme 3D is like a diffuser from The Arabian Nights. Its handblown glass bottle illuminates with a beautiful inner fireworks display that is spectacular at night. It’s also one of the quietest diffusers we tested and has a strong steady mist that will last for three hours.

With a 12-hour reservoir capacity and steady output, the InnoGear – Premium 500ml is our pick for large spaces. It’s also a unique style option that some of our testers loved.

The rest of the options all have their pros and cons, but for the money the Smiley Daisy – Hibiscus provides the best value and the best performance across all the metrics we tested.

Top Pick: Smiley Daisy - Hibiscus

A top performer across every category while still maintaining affordability, the Smiley Daisy is our recommended choice.

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Daniel Jackson, Writer

Daniel is a Canadian farm boy who grew up to be a nerd with a literature degree and too many hobbies to count. He emigrated from Canada to California in 2013, and now writes for Your Best Digs full-time. Daniel remains unapologetic about Canadian spelling, serial commas, and the destruction of expensive travel mugs.