Air filters and air purifiers are the two critical components used to clean the air inside our homes. Most homeowners are not aware of the differences between the two units, so they use the terms “air filters” and “air purifiers” interchangeably.

Air conditioning on the wall above the sofa cushions.

Air Filter vs. Air Purifier

While both serve the same purpose, there are some major differences between the two. Below, we’ve highlighted those differences and how you can choose the best unit based on your unique needs. 

What Are Air Filters and How Do They Work?

 An air filter is a sieve-like structure designed to trap small and large particles such as fibers, pollen, mold, and bacteria in the air. Air filters are used inside an air conditioning unit, often between a furnace and the air duct.

When air enters the HVAC system, it passes through the air filter. This filter traps different types of particles before letting the clean air out of the unit and into your home. 

When choosing an air filter, you should pay attention to the MERV rating, filter quality, and sizing/dimensions. Some of the best filters are made of pleated paper and have a MERV rating of 8, 11, or 13. The MERV-13 filters effectively remove dust particles, pollen, spores, bacteria, and other microscopic pathogens, so it’s ideal for maximum air filtration.

Some air filters are reusable, meaning you can wash and replace them. Others aren’t reusable and must be replaced every three or six months, depending on the make. 

What Are Air Purifiers and How Do They Work?

 Air purifiers are devices designed to remove air pollutants. Unlike air filters that are used inside an HVAC, air purifiers are stand-alone units. They also work by killing pathogens instead of trapping them.

Air purifiers draw air from the room via a vent before passing it through several filters. These filters kill bacteria, allergens, and other microscopic elements using different mechanisms, such as UV radiation or electrically charged fields.

Once the air is clean, it’s deodorized to remove odors and other harmful components before a fan blows the purified air into the room.

Since air purifiers kill pathogens instead of trapping them, they are more effective than most air filters in the market. Even so, a high-quality air conditioning unit with a MERV-13 air filter can accomplish the same goal. 

Choosing the Right One for Your Needs

 The goal is to understand your home air purifiers and quality needs and choose the best that solves the issues at hand. For instance, if you struggle with mold infestation and don’t have a budget for a high-end air filter and AC unit, an air purifier will do.

Similarly, you can upgrade your air filter to a MERV-13. If you need further guidance or have other issues with your existing AC system, be sure to enlist the help of HVAC professionals such as 888 Heating.


 Air filters and air purifiers are two important devices that are quite effective in keeping the indoor air clean, fresh and pathogen-free. Choosing either of these products narrows down to your unique needs and expectations.

However, it’s not always a matter of having an air purifier or an air filter; the quality and efficiency of the unit you are using is just as important.  

Air Filter vs. Air Purifier, Air Filter vs. Air Purifier: Which One Should You Choose?, Days of a Domestic Dad