What’s the Difference Between Air Purifier and Humidifier?

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What's the Difference Between Air Purifier and Humidifier?

There are many benefits to using both an air purifier and a humidifier, however, there’s also a lot of confusion around the different uses or purposes of these machines and which is most likely to give you the results you’re looking for.

Both air purifiers and humidifiers are used to improve the air quality in your home, but they do this in very different ways and provide very different results. This may make you google: what’s the difference between air purifier and humidifier?

Here, we are going to take a look at the difference between an air purifier and a humidifier, the uses for each of these machines, and the potential pros and cons of introducing them into your home. This should enable you to identify which will provide you with the best results and which is likely to best meet your specific needs.

We’ll also take a look at what criteria you might want to look out for when choosing your own air purifier or humidifier to ensure that you’re getting the best deal and the most effective product.

Some air purifiers and humidifiers can be used together in the same room. But this isn’t always the case as some humidifiers will damage the filters used within some air purifiers. As a general rule, if you’re planning to use an air purifier and a humidifier together, be sure to carry out some preliminary research to ensure that you’re choosing compatible models.

Related: The Best Whole House Air Purifier for Cleaner Air

Difference Between Air Purifier and Humidifier

What is an Air Purifier?

An air purifier is used to remove allergens, pollutants, and contaminants from the air. As the air passes through the purifier, the filters will trap the pollutants and prevent them from being dispelled back into the environment. Clean air is then sent back out through the machine’s fan, thus purifying the air in your home.

Different models of air purifiers will use different technology to do this. Typically, basic models will use HEPA filters, which are pretty effective in trapping harmful particles. More advanced models might use ionizers, which add negative ions into the space. These ions then attract and trap allergens and bacteria, therefore improving the air quality.

Air purifiers are generally very effective and lots of models also have a built-in activated carbon filter that will remove odors from the room. Air purifiers are popular among pet owners and those with asthma, seasonal allergies, or sensitivities to dust.

Most air purifiers come with reusable filters that can be easily cleaned, allowing them to last much longer and work more effectively. Filters should be cleaned around once every one to two weeks in most cases.

ImageProductOur RatingPrice
Top Choice
Winix 5500-2 Air Purifier with True HEPA
Winix 5500-2 Air Purifier with True HEPA
  • PlasmaWave acts as a permanent filter and includes odor reducing washable AOC carbon filter
  • Smart Sensors gauge the air quality and auto modes for silent nighttime operation
  • True HEPA filter captures 99.97% of airborne pollutants
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Germ Guardian True HEPA Filter Air Purifier with UV Light SanitizerGerm Guardian True HEPA Filter Air Purifier with UV Light Sanitizer
  • 4 in 1 air purifier with a true HEPA air filter 
  • Kills germs with UV C light, traps allergens, reduces odors with activated charcoal filter
  • Quiet operation with a low setting for nighttime use
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Best Value
Hamilton Beach TrueAir Air Purifier with Permanent HEPA Filter
Hamilton Beach TrueAir Air Purifier with Permanent HEPA Filter
  • High-performance HEPA Grade filter that easily vacuums clean
  • Compact, stylish design that can be placed vertically or horizontally
  • 3 versatile speed settings, including quiet whisper setting for nighttime use
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There are many potential benefits to using an air purifier within your home, but there are also some limitations and cons you might want to consider. Let’s see how these weigh up:

Pros of Using an Air Purifier

  • Air Purifiers are great at removing common allergens such as dust and pollen. Many hayfever sufferers or asthmatic people consider air purifiers to be a holy grail in their day-to-day life.  
  • They can also eliminate any harmful chemicals and reduce the chances of disease or virus transmission.  
  • Their ability to neutralize unpleasant odors makes air purifiers a popular choice amongst pet owners and smokers. They’re also just generally great for keeping your home smelling and feeling fresh.  
  • Lots of users also claim that having an air purifier helps them to get better quality sleep. This could be due to the reduction in irritation caused by allergens which in turn reduces nighttime congestion.
  • Finally, air purifiers also help to prevent any mold or mildew build-up in the home. They effectively remove mold spores from the air which can cling to surfaces and fabrics and lead to various health problems.

Related: Air Purifier Benefits for Health and Wellness

Cons of Using an Air Purifier

  • While Air Purifiers are great for removing air-borne pollutants, they won’t do much to combat particles that have settled on surfaces and fabrics, which is typically where most allergens and mold spores can be found.
  • Some models of air purifiers emit ozone, which can be damaging to the chest and lungs. These are most common in air purifiers that use ionizers to clear the air.  

What is a Humidifier?

Now, let’s take a look at air humidifiers, and how these differ from air purifiers.

Air humidifiers don’t work to remove toxins or pollutants from the air, instead, they will add humidity and moisture into the air. They emit regulated amounts of water vapor into space in the form of a mist.

There are three main variants of humidifiers.

  1. The first is an evaporative humidifier. These use a filter and fan system that blows cool moisture into the air.
  2. Ultrasonic humidifiers use oscillating ultrasonic waves to break down water molecules and produce a cool mist.
  3. Steam-based humidifiers boil water and emit a warm mist into the air.

Humidifiers are used to regulate the humidity levels within the home, which should be around 40-50% in most cases. Humidity levels might fall due to increased use of heating systems in colder months and this can lead to symptoms much like that of a common cold including sore throats, sneezing, eye irritation, and dry coughs. It can also cause or exacerbate skin conditions such as eczema and psoriasis. 

Like air purifiers, humidifiers are also frequently used by allergy sufferers. While humidifiers won’t remove the allergens from the air, they can help greatly relieve symptoms.

Humidifiers do require some maintenance as they can quickly become unsanitary if not properly cleaned regularly. It’s recommended that you clean your humidifier once per week if it is being used frequently. To do this, simply unplug the humidifier, remove the tank and give it a good clean using soapy water or some diluted white vinegar.  Be sure to rinse thoroughly before reassembling your humidifier.

Related: Can a Diffuser Be Used as a Humidifier?

ImageProductOur RatingPrice
Top Choice
Everlasting Comfort Ultrasonic Cool Mist Humidifier
Everlasting Comfort Ultrasonic Cool Mist Humidifier
  • Ultrasonic humidifier has 1.6 gallon tank that works in rooms up to 500 sq feet and lasts for up to 50 hours
  • Includes essential oil tray to circulate into the cool mist
  • 2 year replacement policy
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Best Value
AquaOasis™ Cool Mist Humidifier
AquaOasis™ Cool Mist Humidifier
  • Quiet ultrasonic humidifier runs for continuous 24 hours with auto shutoff
  • Multiple mist settings and 360° rotating nozzle for direction control
  • Lifetime warranty
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LEVOIT Wi-Fi Cool Mist Humidifier
LEVOIT Wi-Fi Cool Mist Humidifier
  • Smart control via the free VeSync app to monitor humidity in real-time with programmed timers, customized schedules, voice control, or let the auto mode make adjustments for you
  • Ultrasonic, customizable, quiet mist for 40 hours
  • BPA-free, essential oil tray
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So what are the pros and cons of using a humidifier in your home?

Pros of Using a Humidifier

  • Humidifiers can be extremely helpful for babies who are born in colder months and are showing signs of congestion. Specialist baby humidifiers can be purchased but most cool-mist humidifiers will be suitable, just do some research before purchasing, and if in doubt you can always check with the manufacturer.  
  • Humidifiers are incredibly useful for those who frequently suffer from dry skin or conditions such as eczema which are typically worsened by cold weather and dry air. Humidifiers can significantly relieve symptoms and prevent flare-ups.
  • They’re also great for relieving cold and flu symptoms and enabling more restful sleep. They can also help to prevent nose bleeds and sinus problems.

Related: Humidifier Benefits and Side Effects to Be Aware Of

Cons of Using a Humidifier

  • If used in excess or not cleaned thoroughly and regularly, humidifiers can cause mold and mildew to grow in the home. If there is bacteria present within the humidifier tank, mold spores can be emitted into the air and these can be extremely damaging to your health.
  • Humidifiers do not work to purify the air, so although they may help to alleviate allergy symptoms, they won’t actually remove any allergens from the home.  
  • It’s generally pretty difficult to monitor your home’s humidity levels without specialist equipment. This makes it easy to overuse humidifiers and you could end up adding too much moisture to the space and causing countless issues for the health of you and those you live with. Too much moisture can not only lead to mold but also to the proliferation of dust mites and other types of bacteria.

Which is The Best Option?

So how do you know whether you need an air purifier or a humidifier? This will depend on what you’re looking to gain from using one of these machines. Although they may look similar, both do very different things and will give you very different results. Let’s break things down.

Air purifiers are generally best for those with seasonal allergies such as pollen or dust allergies. They’re also great for those with pets, people with asthma, or anyone who wants to remove unpleasant odors from within their home.

Air purifiers work well in most spaces, but they’re not always necessary. If you’re not showing any symptoms or irritation or allergic reactions, an air purifier probably isn’t totally necessary.

Humidifiers are best used in homes where heating systems or air conditioning units are also being frequently used. They will help to alleviate dry skin conditions and congestion caused by a lack of moisture within the air. They can generally be used safely around babies but need to be cleaned frequently and thoroughly to avoid bacteria build-up or the emission of mold spores.

It’s also easy to overuse humidifiers, so it might be a good idea to invest in a basic humidity monitor for your home to avoid too much moisture being emitted and the growth of mildew.

ImageProductOur RatingPrice
Top Choice
ThermoPro TP50 Digital Hygrometer Indoor Thermometer
ThermoPro TP50 Digital Hygrometer Indoor Thermometer
  • Humidity meter with humidity level icon indicates air condition -- DRY/COMFORT/WET
  • Updates every 10 seconds, has a tabletop stand and a magnetic back to attach to the fridge
  • Can also be as a refrigerator thermometer, freezer thermometer, reptile thermometer, soil thermometer, humidor hygrometer, cigar hygrometer, and more
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Best Value
ThermoPro TP49 Digital Hygrometer Indoor Thermometer Humidity Meter
ThermoPro TP49 Digital Hygrometer Indoor Thermometer Humidity Meter
  • Face icon comfort indicator for DRY/COMFORT/WET air condition and large display numbers
  • High accuracy with refreshed updates every 10 seconds
  • Multiple mounting options: Tabletop Stand / Magnetic Back / Hanging Hole
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Indoor Humidity Thermometer Hygrometer
Indoor Humidity Thermometer Hygrometer
  • 2-pack, easy to use and install digital hygrometer thermometer
  • Separate probe sensor for humidity and temperature, and 18 ultra-large sensitive vents, measuring the change per 10 seconds in real-time
  • Company offers a full refund for a worry-free purchase
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Lots of people choose to use purifiers and humidifiers in conjunction with one another, just be sure to check the product details to ensure that this can be done safely.

Choosing the Best Air Purifier

Should you decide that an air purifier is going to benefit you and your home, there are a few things to consider before investing. There are many affordable options on the market, but air purifiers can also be pretty expensive, so it’s important to know what to look for and to be aware of the key criteria that can be found in a high-quality, effective air purifier.

Models with easy-to-clean reusable filters are generally going to be the most eco-friendly and cost-effective. Disposable filters are often not recyclable and purchasing replacements can be expensive.

Look for a model with a high CADR rating. This tells you how effective it is in removing pollutants, so the higher the better.

You should also refine your search to find air purifiers designed specifically to meet your needs. For example, if you suffer from pet allergies, look for a model that will catch pet hair and remove common allergens from the air.

Always look at the customer reviews and shop around before investing in your air purifier. The market is incredibly saturated, so you’re sure to find a model to suit you.

Winix 5500-2 Air Purifier with True HEPA, PlasmaWave and Odor Reducing Washable AOC Carbon Filter Medium , Charcoal GrayWinix 5500-2 Air Purifier with True HEPA, PlasmaWave, and Odor Reducing Washable AOC Carbon Filter Medium

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Choosing the Best Humidifier

Similarly, humidifiers vary greatly from model to model. Which one you choose to purchase will depend on what you intend to use it for and the results you are hoping to get from your humidifier. Look out for these key things:

  • Choose a humidifier with an easily removable water tank. The tank will need to be cleaned regularly so it’s vital that you can access it easily, particularly if you’re going to be using the humidifier around babies or young children who may be more susceptible to congestion and chest problems.
  • The type of humidifier you choose will depend on your own needs. Cool mist humidifiers are the safest option as they reduce the risk of burning. They also tend to be much more economical and cost-effective in the long run.
  • If the sole purpose of using a humidifier is to reduce congestion or symptoms of cold or flu, consider purchasing a small, personal use humidifier. These can be placed on your nightstand to aid better and more restful sleep, but are less likely to cause dampness or mold within the home.

Related: What is the Ideal Indoor Humidity in the Summer and Winter?

AquaOasis™ Cool Mist Humidifier {2.2L Water Tank} Quiet Ultrasonic Humidifiers for Bedroom & Large room - Adjustable -360° Rotation Nozzle, Auto-Shut Off, Humidifiers for Babies Nursery & Whole HouseAquaOasis™ Cool Mist Humidifier {2.2L Water Tank} Quiet Ultrasonic Humidifiers

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Final Thoughts on What’s the Difference Between Air Purifier and Humidifier?

Air purifiers and humidifiers both work to improve the air quality in your home and if used effectively, can be extremely beneficial to your health and the health of those living within your household.

However, air purifiers and humidifiers will give very different results and work in different ways to give you the best air quality possible.

Some households may benefit more from the regular or occasional use of an air purifier, while others may benefit from the use of a humidifier. This will depend on your own personal needs, the location and condition of your home, and the results you are looking to achieve.

Now that you know the answers to the question “what’s the difference between air purifier and humidifier?” And by learning more about what each machine does, its benefits, and its limitations, you should now be well equipped to decide which is the best choice for you and how to go about finding an effective and good-quality air purifier or humidifier to introduce into your home.