Oct 14, 2024
The 4 Best Essential Oil Diffusers of 2024 | Reviews by Wirecutter
By Dorie Chevlen and Shannon Palus We’ve retested all our picks—they remain the same—and added new testing notes. An essential oil diffuser offers a simple way to make your home smell nice without the
By Dorie Chevlen and Shannon Palus
We’ve retested all our picks—they remain the same—and added new testing notes.
An essential oil diffuser offers a simple way to make your home smell nice without the use of scented candles or incense.
After our tests of more than a dozen different diffusers, the Urpower 2nd Gen 300ml Aroma Essential Oil Diffuser—our pick since 2017—continues to be the best choice.
This diffuser produces a strong mist and lasts several hours between refills. But you have to cycle through every light option to turn it off.
May be out of stock
With a larger, 500 mL tank, this diffuser doesn’t require refills as often. However, it takes up more space than our top pick.
This compact model is the most attractive diffuser we recommend, but its smaller tank doesn’t last as long as our pick’s, and its mist isn’t as powerful. It’s also far pricier.
If your top priority is a strong smell, go with a nebulizer. This model is pricier than our top ultrasonic pick and harder to clean, but it’s unbeatable at filling a room (or a few) with scent.
Most of our picks are ultrasonic: They create a cool mist of water and drops of oil. Nebulizers diffuse pure essential oils only.
The best diffusers have one simple, easy-to-clean lid. Decorative double lids can look pretty but can involve more disassembly.
Most diffusers are made of plastic. Even those advertised as “stone” or “wood” are still plastic inside.
Tanks holding between 300 mL and 500 mL have a small footprint but provide a long-lasting mist session.
This diffuser produces a strong mist and lasts several hours between refills. But you have to cycle through every light option to turn it off.
May be out of stock
The Urpower 2nd Gen 300ml Aroma Essential Oil Diffuser is a simple white plastic cylinder in a field crowded with funny shapes and faux wood. It’s one of the least expensive diffusers we’ve looked at, yet it works better than models four or five times the price.
The medium-size tank provides water for around seven hours; you need to add more oil during that time for continued scent. The machine lights up in seven colors (two brightnesses each), but you have to cycle through all those options to turn the light off. It offers a timer function, it has LED indicator lights that aren’t distractingly bright, and it’s easy to keep clean.
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With a larger, 500 mL tank, this diffuser doesn’t require refills as often. However, it takes up more space than our top pick.
If our top pick is sold out or you’d like a bigger tank, we recommend the Urpower 500ml Aromatherapy Essential Oil Diffuser, a larger version of our top pick. It produces the same strong, rich mist as its smaller counterpart does.
At nearly double the tank size of our top pick, this 500 mL diffuser requires fewer refills—and it has a low-output mode that can run for up to 16 hours. However, a diffuser of this size also takes up more space. Like our top pick, it comes with a faux-wood base or in all-white. It also lights up in seven colors, has a timer similar to that of our pick, and is easy to clean between uses.
We’ve frequently seen the price for this larger version be lower than that of our top pick, but often some colors are sold only via a third-party seller on Amazon instead of Urpower itself. (In general, we prefer not to link to third-party sellers; we have bought from this one, though, and have had no problems.)
This compact model is the most attractive diffuser we recommend, but its smaller tank doesn’t last as long as our pick’s, and its mist isn’t as powerful. It’s also far pricier.
If you’d prefer a diffuser that looks nicer and you don’t need to diffuse scent in a large space, we recommend the Vitruvi Stone Diffuser. With a ceramic shell available in several neutral colors, it’s a stylish diffuser that still emits a decently strong mist and is easy to use.
It’s one of the few diffusers we tested with a truly subtle indicator light (positioned on the back of the unit), making it the best choice if you want to run it while you’re sleeping. The tank is small, though, at 70 mL, so you have to refill it more often, and the two layers of lids make cleaning and refilling slightly more annoying than with our top pick and runner-up. At around $100, it’s also considerably pricier.
If your top priority is a strong smell, go with a nebulizer. This model is pricier than our top ultrasonic pick and harder to clean, but it’s unbeatable at filling a room (or a few) with scent.
If you want a device that does the best job of dispersing scent in a large space or across multiple rooms, and you don’t mind spending more money, the Organic Aromas Raindrop 2.0 Nebulizing Essential Oil Diffuser is a nebulizer that mists pure oil. (In contrast, our ultrasonic picks dilute the oils with water.)
Unlike with our other picks, the colored lights on this diffuser are more subtle, and it doesn’t issue a constant visible stream of mist; instead, it produces a subtle intermittent spritz every other minute. Compared with other models of its kind, it’s less expensive, prettier, and far quieter, as nebulizers typically make loud grinding or buzzing sounds.
The Raindrop 2.0 runs for two hours, and an automatic shutoff helps you avoid overdoing the smell. Like all nebulizers, it’s annoying to clean.
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This guide is based on the original research and testing of writer Shannon Palus, who interviewed various experts, including Nena Bowman, PharmD, DABAT, the managing director of the Tennessee Poison Center, to discuss the risks associated with kids getting into your essential oils. In 2024, staff writer Dorie Chevlen retested all of our existing picks to confirm whether they were still up to our standards. Senior staff writer Tim Heffernan, who wrote our guide to humidifiers and our guide to air purifiers, conducted tests to see how the essential oil diffusers affected air quality, using the same particle counter he uses for testing air purifiers.
Unlike candles, a diffuser can’t catch fire, and you can leave it on while you’re away or sleeping. You can also vary the scent just by choosing a different oil.
But diffusers do come with a few annoyances: Diffusers take a couple of minutes to set up, and they need cleaning every few uses. And if you have small kids or pets in the house, or if you have respiratory problems, there are health-related reasons to consider skipping a diffuser.
According to the experts writing on the American Academy of Allergy Asthma & Immunology’s website, as of February 2020, no studies have explicitly looked at the effects of using an essential oil diffuser on symptoms of asthma. But it’s good to exercise caution if you have asthma: “Anecdotally, there have been reports of respiratory symptoms in asthmatics and non-asthmatics due to a variety of diffused essential oils,” the AAAAI experts write.
If you have small children, using a diffuser involves additional considerations. Plan to store your essential oils out of reach, as they smell good enough that kids might assume that they are also tasty. Many oil bottles lack childproof caps, and many oils can be harmful even if ingested in only small amounts. And ingesting citrus and cinnamon oil can cause painful irritation, said Nena Bowman, the managing director of the Tennessee Poison Center.
Likewise, if you have pets, keep essential oils out of reach from them, and diffuse oils with caution. Although the biggest danger comes when people apply oils to their pets (which you should never do), you should also avoid putting certain oils in the air, as the oil can settle on their fur. In our article “Are Essential Oils Safe for Pets?” senior staff writer Kaitlyn Wells lists which specific oils to steer clear of. If you have a bird, skip the diffuser altogether: Birds’ lungs are sensitive.
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Search for “essential oil diffuser” on Amazon, and you’ll get pages upon pages of devices that are all slight variations of one another—many with buttons that look identical. The company that makes our top pick even confirmed to us that some of the manufacturers get their diffuser parts from the same place.
Ultrasonic diffusers are the more popular type because they’re affordable and they put out a subtle scent, using a vibrating diaphragm to turn a solution of water and oil into a fine, cool mist. Nebulizers, which blow compressed air through concentrated oil to turn it to mist, produce a stronger smell, and they usually cost more and can be noisy.
Note that the word ultrasonic applies to some humidifiers as well, but oil diffusers are not humidifiers—even though diffuser manufacturers sometimes advertise them as such. If you were to run and refill an oil diffuser continuously, it would distribute around 1,000 mL of water over 24 hours. Good humidifiers have much larger tanks and humidity sensors that can distribute far more water over a longer period without needing to be refilled—and they are better able to maintain properly humidified air in your home.
Most of our picks in this guide are ultrasonic, and the features you typically see in ultrasonic diffusers informed our selection criteria. Here are the factors that set the best models apart:
We browsed through hundreds of oil diffusers for sale online and eliminated dozens that didn’t meet our criteria. We ended up testing 17 diffusers for four weeks. We used our selections at home, quickly eliminating a few for undesirable design elements or confusing buttons.
We observed the diffusers running side by side to compare the size and height of their mist streams, the key factors in how well they distribute oils. Then we ran the diffusers for several hours to confirm how effectively they scented the room.
We rotated the diffusers through various locations: kitchen counter, living room next to a litter box, guest room, bookshelf, atop a toilet tank, and on a table in a dark bedroom at bedtime, noting how bright the indicator lights were and paying attention to any annoying sounds.
This diffuser produces a strong mist and lasts several hours between refills. But you have to cycle through every light option to turn it off.
May be out of stock
Various versions of the Urpower 2nd Gen 300ml Aroma Essential Oil Diffuser have been our top pick since 2017.
It can run for about seven hours. The 300 mL tank is three times the size of those in most other similarly priced diffusers, which allows it to continually produce mist over twice as long. In addition to being able to run until it’s empty (when it automatically shuts off), this diffuser has timer options to run for one, two, or three hours—a common but not universal feature.
It has the strongest mist stream. The mist from our top pick is one of the strongest we’ve seen in comparison with similar-size units, and that translates to a strong scent that fills the room. If you prefer a more subtle scent, you can use less oil.
It’s nondescript (in a good way) and a great value. This model’s cylindrical, plain white plastic design was one of our favorites in a field filled with strange shapes and fake plastic wood. And it takes up half the footprint of many other models, including some with smaller tanks. At just under $30, and frequently on sale for less, it performs very well for the price—ours has been running well since 2019, with no issues. Although you can set the diffuser to glow in seven different color options (two brightnesses each), you can also use it without a light. The small yellow-green LED indicator next to the mist button is less noticeable than the red and green light on several of the other units we considered. Plus, this diffuser is pretty quiet, though as with most ultrasonic diffusers, you can hear a subtle whirring sound if you get close.
It’s easy to clean. Compared with units that have a second, decorative lid, this model is easy to wipe down between uses. All diffusers need regular cleaning, but senior staff writer Jackie Reeve says the process of cleaning hers is “pretty unfussy, even when we haven’t used the diffuser in a while and it needs extra attention.”
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With a larger, 500 mL tank, this diffuser doesn’t require refills as often. However, it takes up more space than our top pick.
The Urpower 500ml Aromatherapy Essential Oil Diffuser produces an equally strong mist in comparison with our pick but has a larger water tank and a wider footprint.
It can run for up to 16 hours. This model’s 500 mL tank is nearly double the size of our top pick’s tank and about five times the size of those in other, similarly priced diffusers. Unlike all the other diffusers we tested, this 500 mL Urpower model has a “low” mode to produce a weaker mist that can last up to 16 hours. (It lasts about 10 hours on the higher setting.) It also has timer options to run for one, two, or three hours.
It’s beefier. Measuring about 6.5 inches in diameter, in contrast to just over 4 inches for our top pick, the 500 mL version takes up more space on a counter. The difference isn’t significant, but it is something to keep in mind if space is at a premium or if you prefer to run shorter sessions and want to avoid having standing water in your diffuser.
It has the same lights and looks as our top pick. The 500 mL Urpower diffuser has seven options for light colors with two brightnesses each, or you can run it with no light at all. The green indicator light is less bright than that of our top pick, a plus if you’re running the diffuser while you sleep and need near-total darkness. As with our top pick, you have to toggle through all the light settings to turn the illumination off. This model also comes in an all-white option, as well as a few more faux-wood “stain” options than our top pick.
You can usually find it at a great price. At times we’ve seen the 500 mL Urpower diffuser at a lower price than our 300 mL top pick, but some of the color options for this model are typically sold only via a third-party seller on Amazon instead of Urpower itself (though the item still ships from Amazon). In general, we don’t recommend third-party sellers, but we have bought from this one, and we’ve had no problems. If the 500 mL Urpower model is sold out, we recommend the Asakuki 500ml Essential Oil Diffuser, which is almost identical and performs exactly the same but comes only in faux-wood options.
This compact model is the most attractive diffuser we recommend, but its smaller tank doesn’t last as long as our pick’s, and its mist isn’t as powerful. It’s also far pricier.
If you want a diffuser that’s sculptural and available in subtle, earthy tones, we like the Vitruvi Stone Diffuser.
It’s a beautiful object. This Vitruvi diffuser has a tapered, ceramic shell and comes in several understated colors, including black, white, blush, sage, and terra-cotta. Note, though, that the colors are seasonal and will vary.
It’s very small, but it’s still strong. At 70 mL, the tank in this diffuser is about one-third the size of our top pick’s tank, so you can expect to refill it more often if you want it to run continuously for more than three hours. For a model of this size, the mist is still strong and visible, though not as strong as what you can get from our top pick and runner-up. This diffuser offers an option for intermittent diffusing, which our pick lacks; on that setting it can run for eight hours, by turning the mist on and off every few minutes. We don’t like the intermittent setting as much—in our opinion, the continuous mist makes for a nicer ambience. Not surprisingly, this diffuser has the smallest footprint of any of our picks, at just under 3.5 inches.
Its lighting is subtle. This Vitruvi diffuser has only one light: a small ring of yellow around the bottom. But that light has four settings (dim, bright, pulsing, and off) that make it more elegant, though perhaps not as fun, in comparison with the multicolored light options on our top pick and runner-up. And because the LED indicator lights are small and placed on the back of the unit, this model is the best choice if you want to run your diffuser in a dark space.
The decorative lid can be annoying. This model has two lids, an inner plastic one and an outer decorative ceramic shell, which can be cumbersome to remove when you’re refilling the unit or cleaning it out. And since the tank is small, you need to handle such tasks more often than with one of our larger diffuser picks.
Also, the outer ceramic shell on one of our Vitruvi diffusers cracked when we accidentally knocked it over on the kitchen counter. We don’t expect ceramic to be shatterproof, but this is something to be aware of if you’d prefer not to worry about your diffuser breaking. Vitruvi sells replacement covers should that happen.
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If your top priority is a strong smell, go with a nebulizer. This model is pricier than our top ultrasonic pick and harder to clean, but it’s unbeatable at filling a room (or a few) with scent.
If you want a strong aroma and are willing to accept a more difficult cleaning process, we like the Organic Aromas Raindrop 2.0 Nebulizing Essential Oil Diffuser.
It’s mighty strong. But it uses more oil. This diffuser is capable of dispersing enough scent to fill a small house or apartment. It runs intermittently on about 20 drops of undiluted oil—considerably more oil than the few drops you need for ultrasonic water diffusers. The unit has a dial for you to control the amount of mist and scent that comes out.
It runs for a maximum of only two hours. The Raindrop 2.0 disperses oil for two minutes and then turns off for one minute; after two hours it automatically shuts off.
It looks pretty and is relatively quiet. You can choose from a painted black hardwood or a natural hardwood base. A grippy bottom keeps the diffuser stable. Although this diffuser makes noise, as all nebulizers do, it isn’t very loud unless you have it misting on full blast. The light inside the clear glass automatically rotates through various colors, but you can tap the touch-sensitive button to leave it on a certain color or turn it off entirely. In our tests, the button to turn the light on was sometimes too easy to press by mistake, yet at other times we had to do a couple of taps to turn it off.
It’s harder to clean. You need to clean this diffuser about once a week and between oils. That’s more cleaning than nebulizers with fewer glass parts require—and it’s a more difficult overall cleaning process in comparison with that of our ultrasonic picks.
The fine oil mist this diffuser sprays might cling to surfaces nearby, as one owner notes, so make sure to put nothing near it that can get ruined by oil stains.
If you’re loyal to Muji and its simple aesthetic: The Muji Ultrasonic Aroma Diffuser 3 oz from the popular Japanese retailer has a simple all-white design similar to that of the 300 mL Urpower model but with more subtle attention to detail. Unfortunately, it costs significantly more than our top pick for an even smaller size, about 90 mL. But it’s cheaper than our upgrade pick from Vitruvi, and you can often find it on sale. You can’t change the light to a different color—it’s just a warm white in two brightness settings. Our editor of home coverage has had this diffuser since 2016, and it continues to work perfectly. Muji also sells a larger, 10-ounce (300 mL) diffuser, as well as dozens of essential oil blends.
If you want a very small and cheap diffuser: The 100 mL Urpower 2nd Generation Essential Oil Diffuser is a smaller version of our pick, and it costs much less than the similarly sized Vitruvi Stone Diffuser. But at that size, you have a lot more design options, and we wanted to recommend something more attractive than this plastic-finish model—which led us to the Vitruvi diffuser. We also tested the practically identical InnoGear Aromatherapy Essential Oil Diffuser, which worked great too.
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Clean a diffuser every few days. Manufacturers recommend cleaning ultrasonic diffusers once every few days or uses so that oils don’t build up and nothing can grow in the stagnant water. The maintenance instructions for our top pick recommend using a little fragrance-free dish soap. For a deep clean, Apartment Therapy suggests running the diffuser with a diluted vinegar solution every so often, or about once a month if you use it regularly. If you’re switching oils between uses, wipe out the diffuser with a damp cloth.
Clean a nebulizer once a week. The maintenance instructions for our favorite nebulizer recommend cleaning the device with rubbing alcohol once a week. If you’re switching oils, clean it between uses. If you see oil buildup that doesn’t come off with a regular cleaning, soak the glass reservoir in hot water with some dish soap.
Tap water is fine to use. We used tap water while testing the ultrasonic diffusers, even though some companies suggest using distilled water because the minerals in tap water get propelled into the air along with your oil. The EPA says that it’s perfectly safe (PDF) to use tap water in an ultrasonic humidifier, which puts a lot more water into the air than a diffuser. As we note in our humidifier guide, however, tap water can produce a fine, white dust near the device or leave sediment in the water reservoir.
During testing, we looked at how our essential oil diffuser picks affected indoor air quality. We tested multiple essential oils and blends, using four ultrasonic diffusers—the 300 mL Urpower diffuser, the 500 mL Asakuki model, the Vitruvi Stone Diffuser, and the 100 mL Urpower 2nd Generation model—and the Organic Aromas Raindrop 2.0 nebulizer. In a roughly 200-square-foot bedroom, senior staff writer Tim Heffernan measured how the machines affected the number of airborne particles with the same TSI AeroTrak 9306 particle counter that he uses in testing for our guide to air purifiers. He closed the windows and shut off his apartment’s ventilation system during the tests, and he filled the diffusers with distilled water to ensure that no dissolved minerals made it into the air and affected the results. He added the oils in the manufacturer-recommended quantities.
As we expected, all the machines raised the number of fine particles in the air—after all, they work by doing exactly that. The numbers in the chart below show the increase in particles of a 0.3-micron diameter (0.3 micron being the HEPA test standard):
For each test, Tim ran the particle counter for five minutes with the diffuser or nebulizer off to get a baseline reading of the air quality in the room, after which he turned the diffuser or nebulizer on for 30 minutes at its highest continuous setting. He placed the diffuser or nebulizer on his bedside table, with the particle counter a few feet away on the headboard. After 15 minutes, he moved the particle counter to a second table on the far side of the bed, about 8 feet away, to see if distance affected the airborne-particle count.
We found two main takeaways from our findings. First, the nebulizer showed a much greater increase in particulate levels in the air than the diffusers. That isn’t surprising: Nebulizers create a fine mist of pure essential oil droplets, while diffusers create a mist composed mostly of water with a small amount of essential oil mixed in. (Most diffuser makers recommend about four or five drops of essential oil per 100 mL of water.) The water rapidly evaporates and, as a result, does not show up in the particle counts; what’s left over are the relatively sparse oil droplets.
Second, the diffusers created a fairly uniform concentration of airborne particles throughout the room, while the nebulizer concentrated them in its immediate vicinity—note the dropoff for the nebulizer at minute 20, after Tim moved the particle counter away from it.
So, does any of this matter? It’s well established that fine particles of soot, smoke, and dust have negative health impacts when inhaled, but what about fine droplets of essential oils?
Tim spoke with Sachiko Koyama, an assistant research professor at the Indiana University School of Medicine who co-authored a comprehensive review of the ways in which essential oils’ impacts on the body are affected by the mode of delivery (by inhalation, topically, or by ingestion). In general, she told us, aromatherapeutic uses of essential oils can be considered safe, because the oils themselves are not inherently dangerous when inhaled and because their concentration in the air is low. Koyama noted that much higher concentrations are used in the established practice of smell training, which may help to restore a sense of smell to people who have lost it (including some who lost their sense of smell post–COVID-19). Koyama did note that some people are allergic to components found in essential oils, and that overexposure to essential oils may create sensitivity to them in people who previously were not negatively affected. In addition, as mentioned above in “Who this is for,” there are also anecdotal reports of essential oils negatively affecting the breathing of asthmatics and non-asthmatics alike. And as Wirecutter senior staff writer Kaitlyn Wells reports, some airborne essential oils can be dangerous to pets. But “if you don’t have a specifical allergy,” Koyama said, “for most people I don’t think it will cause a problem.”
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In 2021, we tested the Canopy Aroma Diffuser. Unlike an ultrasonic diffuser or a nebulizer, it evaporates oils directly. You soak oils into a little puck of diatomite, a porous mineral made of the shells of tiny sea creatures; a fan blows air past the puck, evaporating the oil. It’s a neat system in theory because it requires no cleaning beyond an occasional wipe-down. But in practice, we found the scent to be very weak. We also don’t like that this model comes with only one puck—you need to purchase separate pucks to switch scents. The “diffusion well,” a larger diatomite option that holds an upside-down oil bottle, can deliver up to three weeks of aroma, but it works only with tiny, 5 mL bottles, as the common 10 mL bottles are too tall.
The Diffuser World Aroma-Ace nebulizer was the most industrial-looking device we tested: no wood (real or fake), no colorful lights. In our tests it was louder than anything else we evaluated by far, emitting a grinding, buzzing sound as it dispersed oil—it sounded kind of like a refrigerator with a worn-out compressor (video). Diffuser World sells a “sound reducer” attachment that is supposed to dampen the sound, but we found that it didn’t work very well. We also tested the Diffuser World Aroma-Infinity, which costs more than our nebulizer pick from Organic Aromas.
The Now Solutions Real Bamboo Ultrasonic Oil Diffuser is made of real wood on the outside, but the inside is plastic. It has an option for intermittent diffusing as well as a timer—a combination that we didn’t see on many other ultrasonic diffusers. However, in our tests the mist was weaker than what our picks produced.
The Stadler Form Mia Aroma Diffuser looks sleek and has a matte finish, no mood light, and just one button. However, in our tests it produced a weak mist in comparison with our picks, and sometimes the mist was hard for us to see at all, which made it less visually interesting.
The Stadler Form Jasmine Aroma Diffuser, the larger version of the Mia, offers an option to run in intervals, 10 minutes on and 20 minutes off, for 24 hours. While its mist was stronger than the Mia’s, it was still weaker than what we got from our picks.
We used to recommend the Vivitest Ceramic Diffuser as a cheap dupe for the Vitruvi Stone Diffuser; the two models look nearly identical and are made from the same materials. However, in early 2023 we saw that satisfaction with both the product and the seller had significantly dropped. In particular, buyers complained that the Vivitest diffuser simply stopped working after about a year of use.
For past versions of this guide, we also tested and dismissed the Diffuser World Aroma-Express, the InnoGear 500ml Aromatherapy Essential Oil Diffuser, and the Welledia Pleasant Essential Oil Glass Nebulizing Diffuser, all of which are now discontinued. We demoted a previous also-great pick, the Kumi Stone Diffuser, due to supply issues in late 2022. It has now been totally discontinued.
This article was edited by Daniela Gorny and Christine Ryan.
Dorie Chevlen
I cover home decor, but I'm rarely stuck inside. I also write frequently about outdoor gear, personal technology, and health products for Wirecutter.
Shannon Palus
Shannon Palus is a former Wirecutter senior staff writer. She tested countless health and wellness products from 2016 to 2018.
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Tank size: Power: Material:Lids: Timer:Lights: It can run for about seven hours. It has the strongest mist stream.It’s nondescript (in a good way) and a great value. It’s easy to clean. It can run for up to 16 hours. It’s beefier. It has the same lights and looks as our top pick. You can usually find it at a great price. It’s a beautiful object. It’s very small, but it’s still strong. Its lighting is subtle. The decorative lid can be annoying. It’s mighty strong. But it uses more oil. It runs for a maximum of only two hours. It looks pretty and is relatively quiet. It’s harder to clean. If you’re loyal to Muji and its simple aesthetic: If you want a very small and cheap diffuser:Clean a diffuser every few days. Clean a nebulizer once a week.Tap water is fine to use.