When Should You Change Your Air Purifier Filter?

You probably already know the use of an air purifier.

So here’s a simple explanation of what it does: Air purifiers deeply cleanse the surrounding air, rid of pollutants and substances that is not visible to the naked eye. Most importantly, it removes allergens and toxic gases that can be hazardous to our health.

Xiaomi Air Filter

If you have not read much on the device, here is a guide to help choose the best air purifier for you.

When considering to own an air purifier, you may be wondering

How often do I need to change the air purifier filter?

Here’s what you need to know:

  1. Type of Air Filters

  2. Air Quality

  3. Frequency of Use

  4. Filter Change Indicators


Type of Air Filters


Xiaomi Air Filter

There are many types of air filters available in the market and each serves a different purpose. Here is a list of air filters commonly found on the market:

  1. HEPA Filters

  2. Carbon Filters

  3. Permanent Filters

  4. Pre-Filters

HEPA Filter (High-efficiency Particulate Air Filter) is the leading choice of air filters today because of its extensive capabilities of purifying air off hazardous particulates and allergens.


What are the differences between the air filters?

HEPA Filter

HEPA Filters are popular because it has a longer lifespan, and easily traps 99% of all particles and pollutants including smoke, household dust, pet dander, mould spores, pollen, formaldehyde, and other toxic substances in the air. Its capability of effectively trapping micron-sized particles makes it a first choice among high-risk industries and medical centers where sanitation vigilance is crucial.

Fun Fact!
Did you know? The HEPA filter was designed during WWII to help remove radioactive matter from the environment during the Manhattan Project. Since then, HEPA air filter systems had continuously evolved and is now made accessible to household consumers, with combinations of other new air purifying capabilities to suit certain needs.

Carbon Filters

Carbon filters are a favourite in households, especially those with pets indoors because of its ability to remove odor from the air. Carbon filters effectively absorb fumes and odors as air passes through it. Hence, a larger carbon filter will be needed to efficiently filter more air and to avoid frequent replacement. Unlike the HEPA Filter, carbon filters are not able to trap dust, dust mites, pollen, and other pollutants. To reap the benefits of the two, it is common to find Carbon Filters combined with HEPA filters in the market.

Permanent Filters

Permanent filters, or washable filters are filters that can be reused after wiped, vacuumed or washed clean. It is a greener option compared to disposable filters. A problem with permanent filters is that, overtime, it is difficult to clean out the smaller filter spaces that trap small particles. Hence, permanent filters are often an option for mainly filtering larger particles such as dust. They are not the most effective in filtering allergens and odor unless it is meticulously maintained. Regular checks are required to ensure the filter is performing efficiently.


Pre-filters are air systems that remove larger micron contaminants from air or water. Air pre-filters are commonly found in air regulators in cars, public and commercial buildings, and public transports to remove irritants such as dust, hair, pollen, fibers, insects and more before it delivers air to the designated area. 

Xiaomi Air Filter

Air Quality

Air purifiers are marketed towards effectively improving the air quality based on these 3 matters: Particulates, Gases and Allergens.

Depending on the environment that you wish to purify, the dirtier the air, the sooner your air filter requires change. For example, homes located along urban highways carry more toxic gases and airbourne matters than homes in the suburb. Hence, requiring more capacity from the air filter. If your family has an active allergy to pollen, air filter changes through Spring and Summer might be required to ensure optimum performance of your air purifier.

Frequency of Use

The suggested lifespan of air purifier filters are estimated based on average use. Hence, if you frequently run your air purifier 24/7, you will need to replace your air filter more often than others. To decide, watch out for these indicators:

Filter Change Indicators

  1. Allergies are becoming more active than usual
  2. A visible layer of dust on the air purifier filter
  3. Frequently wiping dust off floors and countertops
  4. Signals from your air purifier

Some air purifiers are equipped with technology sensors that signals the user of its performance. For example, Xiaomi Mi Air Purifier users are able to view real-time air quality through the OLED Display on the device. For better control, connecting the device to the Mi App allows them to view the air quality report on-the-go and get notifications on updates and the moment they need to change the air filter.


 Xiaomi Air Filter



With all that's said, we recommend to change your filters every 3-6 months although industry standard estimate states a longer lifespan.

To make things simpler, here’s a chart to answer some of your most frequently asked questions:

Air Filter

How often should I change my air purifier filter?

Is my air purifier filter washable?

HEPA Filter

Every 12 to 18 months*


Carbon Filter

Every 6 months*


Permanent Filter

Once damaged. Requires to be cleaned every 3 months.*



Once a month, checked regularly*


*Based on industry standard estimate
**Depend on manufacturer claims


Xiaomi Australia carries a range of Air Purifier Filters:

Air Filters

Xiaomi HEPA Filter

Xiaomi Mi Air Purifier HEPA Filter

Xiaomi Anti Formaldehyde Filter

Xiaomi Mi Air Purifier Anti-formaldehyde Filter

Xiaomi Antibacterial Filter

Xiaomi Mi Air Purifier Filter Antibacterial


  • H13-grade True HEPA Filter
  • True HEPA Filter with filtration efficiency of 99.97% for particle size up to 0.3 microns
  • 360 Degree 3 Layer filtration removes dust, odor, and other harmful respirable particles
  • 360 Degree 3 Layer filtration removes dust, odor, and other harmful respirable particles
  • Removes formaldehyde and other harmful substances with quality coconut activated carbon filter
  • 360 Degree 3 Layer filtration removes dust, odor, and other harmful respirable particles
  • Effectively kills bacteria and dust mites
  • Quadruple purification effect, effectively purifies the air

Filter Layers

  • Primary Filter
  • H13-grade HEPA Filter
  • High-quality activated carbon filter
  • Primary Filter
  • H11-grade HEPA Filter
  • High-quality activated carbon filter
  • Primary Filter
  • Antibacterial
  • H11-grade HEPA Filter
  • High-quality activated carbon filter

Best For

  • Tackling various respirable particles
  • Those who are air sensitive (e.g. asthma, eczema, pollen allergies)
  • Haze conditions
  • Filters formaldehyde and toxic substances in the air
  • Absorbs all kinds of odors (toilet, renovation work, domestic waste)
  • Haze conditions
  • Stuffy rooms
  • Public place with large population
  • Sensitive to air quality such as kids and elders
  • Infectious season
  • Haze conditions


To read more on Xiaomi Air Purifier Filters:
Xiaomi Mi Air Purifier HEPA Filter

Xiaomi Mi Air Purifier Anti-formaldehyde Filter

Xiaomi Mi Air Purifier Filter Antibacterial



Check out more on Xiaomi Air Purifiers here: https://www.mi-store.com.au/xiaomi-air-purifiers

To choose the best device for you, visit https://www.mi-store.com.au/which-xiaomi-air-purifier-is-best