Free Shipping / Questions? Call us: 910-401-3910

Product Collections

1 Inch Air Filters
1 Inch Air Filters
12x20x1 Air Filter
12x20x1 Air Filter
2 Inch Air Filters
2 Inch Air Filters
20x20x1 Air Filter
20x20x1 Air Filter

4 Inch Air Filter
4 Inch Air Filter
Air Filters
Air Filters
Air Purifier Filters
Air Purifier Filters
AP510 Replacement Filters
AP510 Replacement Filters

Aprilaire
Aprilaire
Aprilaire 10 Water Panel Replacement Filter
Aprilaire 10 Water Panel Replacement Filter
Aprilaire 35 Water Panel Replacement Filter
Aprilaire 35 Water Panel Replacement Filter
Atomic Filters
Atomic Filters

Bionaire
Bionaire
Carrier
Carrier
Everpure
Everpure
Featured Filters
Featured Filters

Furnace Filters
Furnace Filters
GE Water Filters
GE Water Filters
Geothermal Air Filters
Geothermal Air Filters
Hamilton Beach Air Cleaner Replacement Filters
Hamilton Beach Air Cleaner Replacement Filters

Holmes
Holmes
Honeywell
Honeywell
Honeywell Whole House Filters
Honeywell Whole House Filters
Hunter Air
Hunter Air

Lennox
Lennox
Lennox MERV 16 Carbon Clean Healthy Climate
Lennox MERV 16 Carbon Clean Healthy Climate
Lennox X6673
Lennox X6673
LG
LG

LG LT700P
LG LT700P
LG Water Filter
LG Water Filter
Maytag
Maytag
Maytag Refrigerator Water Filters
Maytag Refrigerator Water Filters

Samsung
Samsung
Samsung Refrigerator Water Filters
Samsung Refrigerator Water Filters
Shop Air Filters
Shop Air Filters
Skuttle
Skuttle

Sub Zero Refrigerator Water Filters
Sub Zero Refrigerator Water Filters
Totaline
Totaline
Trion
Trion
Water Filters
Water Filters

Whirlpool
Whirlpool
Whirlpool 1183054K HEPA Filter
Whirlpool 1183054K HEPA Filter
Whirlpool Air Filters
Whirlpool Air Filters
Whirlpool Refrigerator Water Filters
Whirlpool Refrigerator Water Filters

Whole House Air Filters
Whole House Air Filters
Nominal Vs. Actual Sizes: Finding the Right Air Filter Size

Buying the Correct Size Air Filter- The Most Important Thing to Know 

When you are buying your air filter online most important thing to know is Air Filters have two sizes that you need to understand the Nominal size and the Actual Size. Not understanding these numbers often leads to consumers purchasing a filter that does not fit their Furnace or HVAC system.

Nominal vs Actual air filter size by Atomic

 

Understanding Nominal Filters Size Could Save You Time and Money

Not understanding the Nominal Filter Size is the primary culprit for incorrectly purchased filters.The Nominal Size are the usually the dimensions used to Label the filter. For instance 16x20x1. These dimensions are a rounded value on the filters actual measurements. The actual measurements on this filter may be 15.5x19.5x.75, but that could vary by brand and manufacturer. So in order to make sure you have the correct size filter, especially if you are replacing with a different brand it is important to confirm the actual size on the filter. When purchasing filters on the internet the Nominal size is usually found the in the product title.

Actual Filter Size- The Key to Making the Right Replacement Filter Purchase

The actual size as you might have guessed are the actual dimensions of the filter by length, width and thickness. This size is often on the filter right below the Nominal size and is usually labeled as the actual size. When you are buying a filter online the actual size is sometime in the product bullet point or the product description. If your filter does not have actual dimensions on the outside of the filter, you can measure you filter to get the correct dimensions. Some brands have a foam gasket on the outside of the filter, in this case you will want to make sure you have a compatible actual size size and that it also has the foam to insure a snag fit. 

Lennox Air Filter X0851 with Foam strips

Examples of Nominal and Actual Sizes

 Size  Example 1  Example 2
Nominal Size 20x20x1 16x20x1
Actual Size 19.5x19.5x.75 15.75x19.75x.75

 

 Furnace filters should fit securely but should not have to be forced into position. If you have to force the filter into its slot, then it is probably too big. Forcing an improper filter size in a filter can cause it to buckle, damaging the filter or reducing its ability to function properly. Filters are a smaller than their slot to allow for easy replacement. Some HVAC units may need a filter with dimensions that are unique or uncommon. In these cases, a custom filter needs to be ordered.

;