Furnace Filters

Furnace air filter ratings indicate how effectively a filter captures airborne particles. For each rating system, the higher the filter rating the better the filtration you can expect. The most common rating systems are MERV, MPR, and FPR:

MERV (Minimum Efficiency Reporting Value) – Most Common

• MERV is a rating on a scale from 1 to 20 (higher MERV rating = better filtration).
• MERV 8-13 is ideal for most homes, balancing efficiency and airflow.
• MERV 14+ is used in hospitals and high-purity environments.

MPR (Microparticle Performance Rating) – developed by 3M

• MPR rating is used to indicate how effectively a filter can capture particles between 0.3 and 1 micron in size
• Rated from 100 to 2800 (higher MPR rating = better filtration).
• Example: MPR 1900-2800 is equivalent to MERV 13+.

FPR (Filter Performance Rating) – Home Depot’s System

• Rated 1 to 10 (higher FPR rating = better filtration).
• Example: FPR 7-10 corresponds to MERV 11-13.

Yes, some air filters can help improve your home's smell. To effectively reduce smells from pets, smoke, cooking, or mustiness, you would want to find activated carbon filters. Similar to a refrigerator air filter, activated carbon furnace filters will provide the best result for reducing unpleasant smells from the air that passes through them. Most standard filters will trap dust and allergens but don’t eliminate odors.

The best air filter for your home depends on your needs, such as allergy relief, pet dander control, or energy efficiency. 

Pleated HEPA (High-Efficiency Particulate Air) filters will be the best choice for overall filtration, but these filters have the potential to reduce airflow if the HVAC system isn’t designed for high-efficiency filters. 

MERV 11-13 filters are best for users who need a step down from HEPA filters but still need to reduce more fine particles like pollen, pet dander, smoke, and mold spores. These filters tend to be a good balance for airflow and filtration efficiency.

MERV 8 filters are affordable and effective for dust, lint, and larger particles. These are a commonly sought-after filter for most homes and are suitable for most standard HVAC systems. Note: MERV 8 do not filter out finer allergens or bacteria. Keep in mind what contaminants you are aiming to reduce.

To learn more about different air filter types or try our sizing guide, visit the Air Filter Finder page. Here you can find more details about air filter ratings and their benefits.

There are some specialty reusable filters that are designed to be cleaned and reused. DiscountFilterStore does not offer these filters at this time. Most standard fiberglass, pleated, and HEPA furnace filters cannot be cleaned. Attempting to wash them can damage the filter media, reducing effectiveness and potentially promoting mold growth if not completely dried. Instead, they should be replaced as recommended (typically every 1-3 months). 

Vacuuming a pleated filter may remove surface dust but it will not restore the filtering capacity. For best performance, it is recommended to simply replace the filter once every 1-3 months.

Home furnace air filters are typically not recyclable due to their mixed materials. Most filters contain a combination of fiberglass, synthetic fibers, cardboard, and metal, making them difficult to process through standard recycling programs. However, some components may be recyclable such as cardboard frames or metal components. Check with your local recycling facility for specific disposal guidelines.

There is not a universal sizing for home air filters. Furnace air filters will come in a variety of sizes with different lengths, widths, and depths depending on the furnace and ductwork installed in your home. Commonly the installer would indicate what size air filter needs to be used for that system. The most common way to shop for air filters is not by the brand or age of the furnace but by the air filter size that fits it and the preferences of the user for filter quality. If you know the dimensions of your air filter you can try our Air Filter Finder.