What’s the Difference Between Humidifier and Diffuser?

Turning your home into a therapeutic, relaxing space can be made easy with a humidifier and diffuser. What’s not easy though is deciding which one you need! They may sound and look similar but both humidifiers and diffusers serve different purposes. Delve further into it, and you’ll find that there are a confusing amount of different types of humidifiers and diffusers. It’s enough to put you off buying one!

Never fear, this handy guide will explain what’s the difference between humidifier and diffuser. We’ll also tell you which one best suits your needs!

What is a Humidifier?

A humidifier is a device which, you guessed it, humidifies the air. Why would you need that, you ask? By adding more moisture into the air, humidifiers fight off the effects of dry air. This includes dry skin, dryness in the throat, frequent coughing and trouble breathing.

Humidifiers are beneficial all year round. Dry air is more frequent in Winter where heaters suck out the moisture in the air. In summer, allergens are more present and air conditioners tend to circulate dry air throughout the home.

Humidifiers come in various types including:

  • Steam vaporisers
  • Ultrasonic humidifiers
  • Evaporators
  • Impeller humidifiers

They also come in different sizes which are capable of humidifying a small room to entire houses.

What is a Diffuser?

A diffuser works similarly to humidifiers in that they also add moisture in the air. However, they also spread essential oils throughout a home or workplace. These essential oils not only smell great, but have different therapeutic effects depending on the essential oil used.

Here are some examples of different essential oils and their benefits:

  • Lavender: lavender essential oil is famous for its ability to calm, reduce stress and improve sleep.
  • Bergamot: the bergamot tree produces an oil commonly used to energise and boost moods. It also eases respiratory problems.
  • Eucalyptus: the oil of the eucalyptus tree is used as a natural insect repellent, decongestant and a method to purify the air.
  • Chamomile: chamomile has long been used as a ‘healing’ oil, treating headaches, improving sleep and relieving tension and stress.

Diffusers work by mixing these essential oils with water and then emitting them into the air. The way they do this is what separates them into their different types. For example, nebulising diffusers use a constant stream of air to disperse the essential oil in the form of water droplets. Ultrasonic diffusers use vibration to break up both essential oil and water into tiny molecules that are emitted into the air.

Diffuser vs Humidifier: Which one do I pick?

Despite the fact they work in almost similar ways, the key difference between humidifier and diffuser is their purpose. Humidifiers are designed to only introduce humidity and moisture into the air. On the other hand, diffusers diffuse essential oils which bring a host of different therapeutic and aromatic benefits.

When deciding which one to buy, looking at each device pro’s and con’s can be very helpful.

Pros and Cons of a Humidifier


  • Added moisture provides relief for sinus and respiratory problems, dry skin and irritated eyes.
  • Provides relief for those suffering from allergies.
  • Can aid those who suffer from insomnia and snoring.
  • Added moisture benefits wooden furniture and keeps them in high quality for longer.
  • Can work with tap water.


  • Most humidifiers require daily cleaning and maintenance to keep them running at optimal levels.
  • Larger humidifiers can be very noisy

Pros and Cons of a Diffuser


  • Has a wider variety of therapeutic benefits depending on the essential oil used.
  • Can either stimulate or bring a calming effect to your mood
  • Introduces pleasant aromas


  • Taking into account the cost of both a diffuser and their essential oils, they are usually more expensive that humidifiers
  • It is usually recommended that you only use distilled water with your diffuser. This is because regular tap water can affect the quality of the essential oils.

It’s also a good idea to ask yourself what you’re exactly looking to add to your room, house or workspace. If your sole need is the added moisture and humidity then a humidifier will completely fulfil your needs. If you’re looking for more than increased humidity and are looking to experience added benefits, a diffuser is most likely your solution.

Improved Well Being No Matter What You Pick

The bottom line is that no matter what you choose, you’ll experience a greater sense of wellbeing. Both devices are capable of introducing benefits which will undoubtedly improve your life.

Dry air can be made a thing of the past with a humidifier and an aromatic environment can be made with a diffuser. It’s a win, either way!

Looking to start enjoying the benefits of your own humidifier? At OSIM, we always keep your health and wellbeing in mind. That’s why we’ve developed the uMist Dream, our premier ultrasonic humidifier. Featuring Ultrasonic technology, the uMist dream creates the ideal humidity level to provide a hydrated, comfortable and healthier indoor environment. Check it out along with our other products, all made to improve your wellbeing.
For more articles like this, be sure to visit the OSIM Wellness Hub.

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