Air Purifier vs Diffuser: Comprehensive Guide 2024

Is An Air Purifier The Same As A Diffuser

Air purifiers and diffusers are two common things that people who are new to the air purifying world are usually confused about. Since air quality is generally getting worse, especially in the urban area, many people turn to different types of air cleaners to improve the air quality in their homes. That being said, with so many different types of devices, it is quite easy to mix them up with each other. Air purifiers and diffusers are just one of the most popular examples. I am going to address one common question that keeps showing up a lot – is an air purifier the same as a diffuser?

The Main difference between Air Purifier vs Diffuser is that an air purifier removes contaminants from the air, making it healthier to breathe. Whereas a diffuser disperses essential oils into the air, providing aromatherapy benefits. Air purifiers are helpful for those with allergies or respiratory problems, while diffusers are used for relaxation or creating a pleasant atmosphere.

No, an air purifier is not the same as a diffuser. These are two completely different devices that do two completely different things. The goal of air purifiers is to clean the air, removing as many air pollutants as possible. On the other hand, we use air diffusers only to add a pleasant smell into the air. So air purifiers actually clean the air, while diffusers do not clean it all and just add some scent. Some air purifiers can actually come with an added diffuser feature, but the opposite does not hold true. So some air purifiers can also be diffusers, but a diffuser can not be an air purifier.

Since air purifiers and diffusers are two completely different devices, we can not directly compare them model to model. But what we can do, is make a general comparison and discuss when it makes sense to use either an air purifier or diffuser. If you want to learn more, read on.

Similarities and differences between air purifiers and diffusers.

First, I want to show you a general overview of the similarities and differences between an air purifier and a diffuser. As I already wrote in the short answer above, these are two different devices that have different purposes. Despite that, they do have a thing or two in common. Check out the graph below to get an overview of similarities and differences.

Air purifier


Cleans the air



Removes odors and smells


No, only masks them

Benefits on the body



Adds scent or fragnance



Alleviates allergies



Can be turned on 24/7



*exceptions apply

Again, the graph above is the general representation of differences and similarities, some exceptions can apply. For example, there are (a very select few) air purifiers that have an added aromatherapy feature – in this case, they do add scents. The same goes for diffusers and their ability to clean the air – not enough scientific research has been done (up to this point) to come to a solid conclusion. Air purifiers, on the other hand, have a proven track record for effectively removing air pollutants, making air cleaner in the process.

When should you use an air purifier?

As the name already suggests, air purifiers purify the air. There are different types of air purifiers on the market today, the most popular being HEPA filters (in combination with other types of filters), air ionizers, UV light, and negative ion generators. Each one of these air purifiers uses a different cleaning technology and specializes in the removal of different pollutants. Here is a great graph that shows which common air pollutant group each type of air purifier removes.

types of air purifying filters for removing different pollutants

While air cleaning methods and effectiveness between air purifier differ, they all have the same goal – clean air. So it makes sense to invest in and use an air cleaner if you:

  • have allergies or any other respiratory issues;
  • are looking for the most effective ways to improve the air quality in your home;
  • have some unpleasant odors or smells in your rooms that you want to get rid of, permanently.

These are the most common examples where you would definitely want to choose an air purifier over a diffuser. Obviously, not all air purifiers are the same and you would need to get the type that fits your needs most. This post is not a guide for that, but the table above should give you a nice starting point.

Now let us look at the opposite question – when should you not get an air purifier? You should not get an air purifier is your main concern is room humidity and room smell (aromas). Air purifiers do not increase or decrease room humidity, so they would not help you in this case. As for the smells – certain types of air purifiers are used to remove smells, not add them. There are some models like this one, which has an added aromatherapy feature; but most air purifiers don’t have that type of feature.

When should you use a diffuser?

Next, we are going to take a look at when does it make more sense to use a diffuser rather than an air purifier.

The purpose of a diffuser is to add a pleasant smell or fragrance into a room. A diffuser has nothing to do with air purifying, which is something that people usually get wrong. 

Most people combine diffusers with aromatherapy, which is a holistic approach to healing through different essential oils. What a diffuser basically does is it absorbs these essential oils and then disperses them into the room. While each essential oil supposedly has a different effect, the common goal for all of them is to freshen up the room and provide positive psychological effects, such as reduced anxiety, improved mood, less stress, boost immunity, and so on. Diffusers are probably one of the most popular ways for utilizing aromatherapy.

That being said, you should consider using a diffuser if:

  • your main goal is to add a pleasant smell and ambiance in your room;
  • you are looking to try an alternative or holistic approach to experiencing some beneficial effect on your health.

Same as it was with air purifiers, there are different types of diffusers. Their main (and pretty much only) difference between them is the method they use to disperse essential oils in the air. Diffusers generally do not have any extra functions, except for humidifying diffusers – they can also add moisture to the room. Other than that, they have no other uses.

Diffusers should not be your “go-to” choice if you are looking for ways to clean or purify the air in your home, or if you want to get rid of strong smells or odors. While essential oils can mask bad smells and odors, they can not remove them. They also can not remove air pollutants which air purifiers can.

Is An Air Purifier The Same As a Diffuser? – Conclusion

To summarize the whole text – no, an air purifier is not the same as a diffuser. While these two devices have a few similarities, they are fundamentally completely different. Some exceptions on certain aspects apply to both sides, but these are in the vast minority.

Both air purifiers and diffusers have their own uses. If your primary concern is air quality and solving respiratory issues, then an air purifier is the way to go. For aesthetics and room fragrance, you should stick with diffusers. While some recent experiments point to possible air cleaning effects of diffusers (in combination with essential oils), no concrete evidence has been presented so far. And even if it was, the air cleaning abilities of diffusers would be limited at best and not really comparable with “true” air purifiers.

If you are mostly after cleaner air and happen to be new to the air purifying world, I have prepared a list of top 5 best air purifiers under $50. These are very budget-friendly, yet very effective for their cost – perfect for anyone looking to dip their toes before investing into something more expensive.

Thank you for reading and I hope you can put this information to good use.

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The author is an Air purifier expert with overall knowledge of air and ionizers.