AC & Furnace Filters

Find Filters

Select the dimensions of your AC or furnace filter. *If you are looking for a 3”-6” thick whole house air cleaner filter replacement, please browse by brand below rather than using this search feature, as nominal dimension can differ depending on the filter brand.

Length x

Width x

Thickness

How do I find the dimensions of my air filter?

Browse Filters by Type

Or Select the brand of your AC or furnace filter

Air Filter FAQs

All Filters offers a number of replacement AC and furnace air filters in both nominal and custom sizes, including popular sizes like 16x25x1, 20x20x1, 20x25x1, 20x25x4, and 16x25x4. Search our selection and find the best filter for your home with choices from OEM and SpiroPure replacement HVAC filters in MERV 8, MERV 11, MERV13, and MERV 10 charcoal carbon odor pleated filter cartridges. Explore geothermal, oil, gas, propane, and electric furnace air filter options.

MERV stands for Minimum Efficiency Reporting Values and is an industry-created standard that evaluates the efficiency of air filters. The MERV rating of any particular air filter ranges on a scale of 1 to 16, with a filter rating 1 being the least efficient and a filter rating 16 being the most efficient.
While it is important for the quality of the air in your environment to choose the most efficient filter possible, it is not always as simple as buying a filter with the highest MERV rating. Because the pores allowing for air flow in a highly-rated MERV filter are very small, the filter creates more resistance against air flow and may put too much pressure on the fan of your furnace, air conditioning, or air cleaner unit. It’s important to choose an air filter with the highest MERV rating that your particular unit will allow for maximum air flow. Information about specific MERV ratings and recommendations will generally be included with the documentation that came with your system.
We recommend choosing an air filter with a MERV rating between 8 and 11 for most residential units in order to adequately remove airborne contaminants. If your system can handle a filter with a higher MERV rating, you may wish to use a filter with a rating of 13 for even greater contaminant removal. However, it’s important to remember that filters with a higher MERV rating must be replaced regularly (every 3 months for 1" filters and every 6-12 months for 3- 6" box-type filters) to avoid restricted air flow and negative effects on your system’s performance.

If you cannot find your filter or need other assistance, please call us or chat with us on Live Help.

Hours of Operation
Monday - Friday	9:00 am - 7:00 pm EST
Saturday & Sunday	11:00 am - 5:00 pm EST