Air Purifier VS Humidifier: Which Is Better?

An air purifier and humidifier are not the same, even though both can improve your indoor air. Both devices come with a unique set of functionality and serve a different purpose. This post will explain the differences between an air purifier and a humidifier without any confusing jargon. Learn how to use both home appliances effectively to alleviate your allergies and create a safer home for your baby.


What Is An Air Purifier?

An air purifier draws air in and captures airborne particles that pass through a series of filters. Good indoor air quality will improve your health with the continuous distribution of clean air. Most air purifiers are equipped with a pre-filter, carbon filter, and HEPA filter. At the same time, premium models come with add-ons such as UV-light or ionizer. Below are the 7 common types of air cleaners for residential use.

What Is a Humidifier?

Humidifier adds water to the air through boiling, water droplets vibration, or evaporation with a fan and wick filter. By increasing the relative humidity level between 30% to 50%, a humidifier can relieve any breathing discomfort due to dry air. EPA recommends using distilled water to refill the reservoir consisting of less harmful mineral particles than tap water. You should also avoid over-humidifying the air as a damp environment could promote the growth of microorganisms. Below are the 4 common types of humidifiers:

  • Evaporative
  • Steam vaporizer/ Mist
  • Ultrasonic
  • Impeller
The Difference Between Air Purifier and Humidifier

The Difference Between Air Purifier and Humidifier

An air purifier is not the same as a humidifier. The difference is that an air purifier cleans the air by removing pollutants such as dust, mold spore, mildew, pollen, pet dander, bacteria, virus, smoke, and odor. It does not release moisture. A humidifier adds moisture into the air to increase the relative humidity level. It does not clean indoor air.

With proper care and maintenance, you can extend the usage life of both devices. Air purifiers need to replace filters every 6 to 12 months, depending on the model. However, air purifiers with a washable filter require a higher frequency cleaning. On the other hand, humidifiers are more troublesome to maintain than air purifiers. Most humidifiers require distilled water refilling every 1 to 3 days, depending on the water tank size. You will also need to clean the water tank weekly to prevent harmful minerals from building up.

There is a big price gap between air cleaners and humidifiers. A cheap air purifier can go under $50 but an expensive model could cost more than $400 . You will also have to account for the high filter replacement cost. In comparison, most humidifiers will only cost under $250 with no recurring filter cost. For a clear comparison, refer to the bottom air purifier VS humidifier table for more info.

Both air purifiers and humidifiers will bring different health benefits to the table. An air purifier is excellent for an asthmatic or hypersensitive person. It can alleviate allergic reactions like cough, sneeze, watery eyes, itchiness, sore throat, or headache due to bad air. It can also reduce the impact of seasonal allergies like allergic rhinitis (hay fever). Some air purifiers can reduce stress and improve mood levels by increasing mood chemical serotonin through ionization. Without the constant exposure to airborne pollutants, an air purifier will protect you from respiratory diseases like COPD, pneumonia, sinusitis, pulmonary edema, respiratory tract damage, bronchitis, dementia, and lung cancer.

Humidifiers improve breathing, ease shortness of breath, clear mucus, and expand nasal passages. You will sleep better with no dry cough, sinus, scratchy throat, nose bleed, or dehydration the next day. Humidifiers can also help with eczema, flaky skin, chapped lips while keeping skin moist and radiant. It can also prevent static shock and help you recover faster from illnesses with increased oxygen circulation.

FeaturesHoneywell HPA300
Air Purifier
honeywell top-fill cool moisture humidifier
DimensionVaries (compact, tower, portable, and console)Small to medium depending on the water tank size
FunctionsClean indoor air by trapping airborne allergens and smokeAdd moisture to increase the indoor humidity level
Alleviate AllergiesYesYes
Help With AsthmaYesYes
Remove DustYesNo
Stop Mold From GrowthYesYes
Best Used InBedroom, living room, kitchen, study room, office, basement, garageDry places, during winter season
  • Mechanical/ HEPA air purifier
  • Activated carbon air purifier
  • UV-light/ UV air purifier
  • PCO cleaner
  • Ionic/ Ionizer
  • Electrostatic precipitators
  • Evaporative
  • Steam vaporizer/ Mist
  • Ultrasonic
  • Impeller
Noise LevelSubtle to loudSubtle (ultrasonic, cool mist), White noise (impeller, warm mist).
Maintenance3-12 months (filter change)24 hours (refill water)
PriceLow to high ($20 to >$400)Moderate (under $250)
Can You Use a Humidifier and Air Purifier In The Same Room

Can You Use a Humidifier and Air Purifier In The Same Room?

Yes, you can use an air purifier and humidifier together in the same room. Both air purifiers and humidifiers have different functionality. One removes airborne pollutants, and the other add moisture to the air for better breathability. However, you will need to keep them at least 2-3 feet apart or separate them with each at the opposite ends of the room. The excess moisture dispersed from the humidifier could clog or damage the HEPA filter and carbon filter when placed too close. For the best of both worlds, consider getting the best air purifier humidifier combo as listed here.

By now, you should have an idea of what an air purifier does and vice versa for a humidifier. If you are still unsure if you need an air purifier or humidifier, here’s the quick recap:

An Air Purifier Would Be Best For You If:

  • Staying in a poor air quality environment.
  • Allergic to dust, pets, smoke, odor.
  • No musty mold smell in the home.
  • Suffer from hypersensitivity or asthma.
  • Relative humidity level is between 30% to 50%.

An Humidifier Would Be Best For You If:

  • Indoor air is dry with humidity level falls below 30%.
  • During the winter season.
  • Breathing trouble as the air feels dry, stale, and stuffy.
  • Allergic symptoms like dry cough, itchy/ flaky skin, chapped lips, or irritated nasal passage.
  • Constant static shock.

Which is Better: Air Purifier Or Humidifier?

  • Allergies - Air purifiers are great at curbing down allergy symptoms by cleaning the indoor air. Humidifiers can add moisture to dry air that helps with a stuffy nose, breathing trouble, sneezing, or sinus inflammation. Otherwise, it will have no impact on allergens in the air.
  • Asthma - An air purifier would be the better pick. Both air purifiers and humidifiers can help with asthma differently. An air purifier captures airborne triggers that are known to aggravate asthma symptoms. A humidifier can ease asthma symptoms by adding moisture into the air to create a more comfortable breathing space. It can prevent air dryness and moisturize your nasal passage, but it cannot remove airborne allergens. If you are on a tight budget, there are plenty of cheap air purifiers out there that can make a big impact in treating asthma.
  • Baby - You can use a humidifier and air purifier for the baby as both work well together without affecting each other performance. When the air is dry, a humidifier helps a baby breathe better and sleep comfortably by relieving nasal congestion through humidification. An air purifier provides clean, fresh air and removes stinky odors in the home. It will protect the baby from allergies and falling sick, especially with their developing immune system. For baby use, we recommend going with a HEPA air purifier and/ or a cool-mist humidifier over a warm-mist.
  • Mold - Air purifiers are the better in dealing with mold and musty odor. It is designed to remove mold and other allergens in the air. On the other hand, a humidifier does not remove any airborne allergens from the air. Over humidifying a room will create a favorable environment for mold to thrive. A dirty humidifier also promotes the growth of mold spores in the water tank.
  • Sinus - Both air purifiers and humidifiers can help with a cold, flu, and sinus infection in different ways. An air purifier with its HEPA air filter capture allergens that causes sneezing, postnasal drip, and sinus infection. A Humidifier disperses moisture to help relieve discomfort from a stuffy nose. Your nasal passage will be well lubricated with less mucus layer building up.
  • Dust - Air purifiers are designed to remove dust in the air by trapping them into its filtration. Humidifiers do not help with dust as it does not clean the air. If you have dust allergies, you will need an air purifier.
  • Snoring - Both can help with snoring through air cleaning and humidification. Air purifiers help reduce snoring triggered by pollution and allergies like inflammation or nasal congestion. Humidifiers help reduce snoring by soothing the upper airway with moisture and preventing inflammation. Dry air is notorious for making a snoring condition worse as it causes the mouth, nose, the throat to dry out.

Max Fernandez

A loving father and a dedicated reviewer for airfuji.com with more than 1000 air purifiers under his belt. Max Fernandez is also one of the million patients currently suffering from asthma. Feel free to nudge him if you have any questions.