Our top choice
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The Urpower diffuser produces a strong mist, lasts a long time between refills, looks great, costs less, and has a smaller footprint than similar competitors.
The Urpower 2nd Gen 300ml Aroma Essential Oil Diffuser is a simple white plastic cylinder in a field crowded with funny shapes and (very) faux wood. It’s one of the least expensive diffusers we looked at, working better than models four or five times the price. The medium-size tank provides water for seven hours of a strong stream of mist (though you’ll need to add more oil during that time for continued scent). It lights up in seven colors, offers a timer function, and has LED indicator lights that aren’t as distractingly bright as those on much of the competition. It’s easy to clean with a cloth.
Runner-up
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This diffuser provides a strong mist and has a larger tank you won’t have to refill as often. However, it takes up more space, and the faux-wood look isn’t for everyone.
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This 500 mL model is almost identical to the Asakuki.
If our top pick is sold out or you’d like a slightly bigger tank, we recommend the Asakuki 500ml Essential Oil Diffuser (or the nearly identical Urpower 500ml Aromatherapy Essential Oil Diffuser). We recommend whichever you prefer on price or aesthetics, and both have a strong, rich, stream of mist that’s on par with that of our pick. At around double the tank size of our pick, 500 mL diffusers requires fewer refills—and in fact, these diffusers are the only style we tested with a unique low-output mode that can run for up to 16 hours. However, a model at this size also takes up more space. They both have a faux-wood base, which some people will find a little tacky. Both light up in seven colors, have a timer similar to our pick’s, and are easy to clean between uses.
Also great
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This compact model is the most attractive diffuser we recommend, but its smaller tank doesn’t last as long and its stream of mist isn’t as powerful as our pick’s. It’s also far pricier.
If you’d prefer a diffuser that looks a little nicer and don’t need to diffuse scent in a large space, we like the Vitruvi Stone Diffuser. With a porcelain shell in a few neutral colors, it’s the only stylish diffuser we tried that both features a strong stream of mist and is easy to use. It’s one of the only diffusers we tested with a truly subtle indicator light (positioned on the back of the unit), making it the best choice if you’d like it to run while you’re sleeping in a dark room. The tank is on the small side, so you’ll have to refill more often, and while it’s easy to wipe out, two layers of lid make cleaning and refilling slightly more annoying than with our top picks. It’s also pricier (but could make a better gift).
Also great
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If your top priority is a strong smell, go with a nebulizer. It’s pricier than our top pick and harder than ultrasonic models to clean, but unbeatable at filling a room (or a few) with scent.
If you want a device that does the best possible job of dispersing scent to multiple rooms at once 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, unlike our other picks, which are ultrasonic. (Here’s a detailed explanation of the difference.) The lights on this diffuser are dim compared with those on our top pick and runner-up, and there’s no cool mist to stare at. It’s less expensive than others of its kind, prettier, and far quieter (nebulizers typically make very loud grinding or buzzing sounds). The Raindrop runs for two hours, dispersing oil intermittently, and an automatic shutoff helps avoid overdoing the smell. Like all nebulizers, it’s annoying to clean.