Diffuser Vs. Humidifier: Which Do I need?


Stark Differences between Diffusers and Humidifiers

When most people think of a humidifier, they think the term can be used interchangeably with diffuser. Well, that couldn’t be further from the truth as those two are totally different in functionality. Their only similarity is the fact that they both use air to carry out their functions.

So, what is the main difference between these two? A diffuser uses essential oil droplets to freshen the air while a humidifier basically keeps a room’s atmosphere moist. Oil not only makes a room aromatic, but it also improves the quality of air within. They cannot be used interchangeably because they are not made to work that way. An oil diffuser has internal workings that make it able to perform the way it does.

More about Diffusers

There are four types of essential oil diffusers; ultrasonic, nebulizing, heat, and evaporative. Each of these is different from the other.

  • Ultrasonic Diffusers

These diffusers are humidifiers in the way they work. When you add water to fill it up then add oil for function, the oils stay at the top where all the action happens. As the water heats up, the oil is broken into tiny particles that are then sent into the atmosphere to aromatize your room.

The oils diffuse into the air for the entire time that the water lasts, letting out mist in the air. While an ultrasonic diffuser’s job is to cleanse the air with aromatic essential oils, it also humidifies it.


  • They are quite cheap.
  • They humidify as well as diffuse the air.
  • They are easy to maintain.


Oil is diluted and so the air is less fragrant.

The Best Ultrasonic Diffusers

Syntus Essential Oil Diffuser

Its wide base makes it easy to place on any surface and the colors are so inviting. Made of bamboo, this humidifier harbors no toxins and so it is ideal for kids’ rooms as well.  Since it uses water to function, it not only humidifies a room but moisturizes air as well.

Onugi 300ml Essential Aroma Humidifier

Its enormous size enables it to keep running for the whole night long. It is reasonably priced and has a wide base that fits in any space. Being quite huge, this diffuser is not ideal for travel but it makes up for that by being the only nightlight you will need by your bedside.

Real Bamboo Wood Ultrasonic Diffuser

This bamboo diffuser that emits no toxins has a 400-square-feet coverage. It not only humidifies and diffuses, but it also acts as an ionizer. For all its functions, this unit is reasonably priced and works excellently with its four timers. It shuts down after an hour so that you don’t have to wake up to turn it off.

  • Nebulizing Diffusers

They are known to be some of the most effective diffusers, thanks to their construction that separates the jet that lets out aromatic steam from the part where you pour in your oil.  The effective steam jet allows you to blend your essential oils for all needs including therapeutic, medicinal, and germ-killing effects. A room-size nebulizer handles a 300-feet room effectively and will keep in aired all night long, and they come in different sizes to accommodate different users. The main difference between these diffuser and other types is the use of water as nebulizers do not use water. Instead, the oil is heated and steam sent into the air. They are also predominantly glass.


  • These diffusers are the most effective and will keep air purified for the entire night if you set them right.
  • Essential oil is not diluted with water and so the fragrances are stronger.
  • It has a separate part for oil addition which makes it quite easy to clean.


  • It is fairly noisy and so it takes a bit of getting used to.
  • It needs a little pipe to add oil into the tiny stream.
  • Since no water is added to dilute the oil, it will not humidifier a room.

Some of the best Nebulizers

ArOmis Orbis Nox Merus Nebulizer Diffuser

This unit has a separate part that holds a 10ml bottle of oil for use during the process. Since there is not water to heat, the jet of steam released is not hot but it fills the room ideally in its concentrated nature. The glass is hand blown and the wide base is from nature’s Beechwood tree that gives this unit a classic look and finish.

This diffuser covers up to 900-square feet and it has a timer that goes off every 60 minutes. You only need to set it to work for the hours you need and it will go off on its own at night. No plastic is used in the construction of this diffuser and so it is BPA-free. The cool steam stays in a room for longer as it is not rushed by heat and so you feel it longer.

Opulence Nebulizer Essential Oil Diffuser

This lavish diffuser from Organic Aromas is a looker that will not only function as it is expected, but will also do so while making your home look good. Made of handblown glass and wood at the base, this nebulizer is toxin-free and allows no mold to grow on it. This makes it safe for children.

The diffuser works as other nebulizers, emitting steamed air from essential oil without diluting it. It has buttons at the front for easy working and an LED signal that lights beautifully at night. It runs for 2 hours before shutting on its own to save your oils has automatically been set to run for two minutes then go off for one. You can always change these settings if you prefer it to run throughout.

This baby covers up to 800 feet and it measures 9-inches tall x 5.6-inches diameter. It is also quite light at 1lb.

Raindrop 2.0 Nebulizing Essential Oil Diffuser

The base of this beautiful nebulizer – that gets its name from its shape – is wood while the rest of the body is made of glass. This makes the object safe for use as it bears none of those toxins that come with some plastic bodies. Like the others in this category, it only 100% pure essential oils as it does not need water for dilution. This nebulizer that covers up to 800 square-feet automatically shuts down after 120 minutes. To conserve oil, you can set it to run for two minutes then of it goes for one. You will be deep asleep by the time it finally goes off.

This unit that is 10-inches high and about 6-inches wide at the base has inbuilt foam that limits the noise escaping the unit.

Heat and Evaporative Essential Oil Diffusers

Heat diffusers heat up the oil so that it evaporates into the air and makes it fragrant. They are ideal for thicker oils such as sandalwood that may not easily diffuse using the other two types of units.  The oil is placed next to a source of heat and left to do its job.

An evaporative diffuser uses a fan to generate wind vs. heat that causes the oil to evaporate into the air. The oil in the diffuser is held in a wick or pad that is absorbent so that it evaporates in the desired fashion.

Benefits of Diffusing using Essential Oils

  • It opens the airways.
  • Clears the air of particles that may cause illnesses.
  • It enables essential oils to absorb easily into the body for aromatherapy.
  • The aroma improves moods and calms the mind.

Cons of Diffusing

  • Essential oils are quite expensive.
  • The best diffusers are quote expensive.
  • The concentration of oil may not be ideal for babies.

More on Humidifiers

Humidity, being the amount of water in the air, makes things easier for us human beings. It prevents the skin and hair from drying out, keeps throats hydrated and we generally feel more comfortable when the air around us is not bone-dry.

There are different types of humidifiers,

Evaporative Humidifier (Cool Mist)

These are quite popular as they are easy to use and quite cheap. You only need to add water to the humidifier reservoir which will be absorbed by the wick inside unit. A fan by the side of the wick blows the steam that forms and the fragrant air is dispersed throughout the room.

Warm Mist Humidifier

These ones expel warm air that disperses through the room to humidify and fill it with fragrance. When water in the reservoir comes to a boil, the steam rises and starts to cool slightly. The warm air is released into a room for as long as your settings allow.

Impeller Humidifier (Cool Mist)

The water filled in a diffuser is spun around by a disk. You will add drops of oil that will remain on top since it does not dissolve in water, and the disk will keep spinning at a high speed. As the water heats, it breaks down the oil molecules into tinier particles that can be easily absorbed into the air. Those tiny droplets fill the air and the room becomes both fragrant and moisturized.

Ultrasonic Humidifier (Warm or Cool Mist)

This humidifier has a metal diaphragm that produces vibrations and sounds. The vibrations break down oils and water into tiny droplets that are propelled into the air. The new air fills the room and keeps it moisturized for as long as the humidifier is set to run.

Can a Humidifier Take the Place of an Oil Diffuser?

Well, an oil diffuser is the best for its job since it does not dilute oils. It meets therapeutic needs of an adult perfectly, but it may not work for kids. Concentrated essential oils may be too much for young children, which is why a humidifier could be a better option. Water dilutes oil to make it less concentrated for those likely to be affected by essential oil blends. A humidifier works not only moisturizes the air to make it easy for a child to breath in their sleep, but it also acts as therapy, thanks to the essential oils used.

Can you put Essential Oils in a Humidifier?

One of the most regularly asked question has got to be, Can I put essential oil in my humidifier? Well, yes and no. In its original construction, a humidifier was made to support the use of essential oils. That changed over time as diffusers became more popular. The modern design of most humidifiers does not allow the use of essential oils. The plastic component in them makes this function near impossible as oil clogs things up. It is not recommended to use essential oil in a humidifier. Why is this?

  • Material Matters

As we mentioned above, humidifiers are mostly made of plastic which is broken down by citrusy oils. Continued use of these oils will slowly eat into your unit and emit toxins while at it. T be safe, use diffusers for essential oils.

  • Timing matters

Timing is of the essence when diffusing oils with 15 minutes per hour being the recommended time. Humidifiers are designed to run continuously but humidifiers can be set to run this way. The idea behind running intermittently is to allow the body to absorb the oil for the benefits you seek. For this reason, humidifiers are preferred for water.

  • Ionic Nebulizing

While a humidifier will disperse small particles of oil into the air, it will not break them into the smallest they can be to help absorption by the body. They will remain quite large and will not be as beneficial to you as they would if they were nebulized.

  • The Heat Ruins Value

Essential oils are best left in their original state as heating them ruins their therapeutic value. Diffusers are likely to expose the oil to heat as per their construction and functionality, which is wrong. The only way to get the most from your essential oil is by using a diffuser.

Which is the Better Option?

It all depends on what you need it for. Diffusers are excellent for aromatherapy while humidifiers are excellent at restoring the ideal room moisture. Better yet, get one of each and use them for their specific purposes.

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