The way to find the proper filter size

There exists a large amount of different sizes of air filters, and you may find it difficult to select a proper size air filter. And we always easily incented by the manufactures, so it is unavoidable that we have to pay much more to buy the replacements.


Take it easy! Some guidance will be provided for you so you can choose the suitable size air filter, find the proper replacement for your house, don’t hesitate with it .



Check the dimension on the side of Air filters


There are two different air filters size of measurements in  most filters, including the nominal size written in the bag print and an adjacent “actual” size on the written in the smaller print. You

can find all of the filters on  Especially labeled by others.


Maybe it is the easiest way for to find the proper size for your air filter, but you are also required to measure I by hand cause not all filters have a size listed on them.


What’s the difference between Nominal and Actual Size in Air Filter Measurements?


Our customers sometimes can get puzzled by the difference between nominal VS actual size listed on replacement air filters.



Nominal Air Filter size

The normal dimensions on the “Nominal” size list often round up or down to the nearest whole or half number to track of dimension sizes for ordering replacement quickly. It means that the air filter can suit the size of the vent comfortably.



Actual Air Size

Normally the actual size of the air filter is often 25’’-5’’ less and displays the actual dimension specs of air filters.



We try our best to measure actual dimensions throughout our website in order to show it clearly, the nominal filter size is the size listed on the large print. If the size is less than 25’’, it’s generally interchangeable.


The way to measure your Air filter Dimension


You have to take out your trusty tape to measure if the size is not written on the side of your air filter.




Measure the length, and width, and depth,but it’s interchangeable for the length and width, but generqally the larger is the width , and the shorter is the length, the smallest is the dimension is the depth.


If an air filter ‘s diomension is 12’’*20’’*1’’ , that means as follows:


●Width: 12’’

●Length: 20’’

●Depth: 1’’



The length and  width is interchangeble , so you need to ensure that s specific air filter dimensions.


you can see an example below:


As for the measure of depth, the standard air filter sizes are normally 1’’(actual 0.75’’)2’’(actual 1.75)  4’’(actual 3.75’’) deep. It is easier to find these genreral air filter sizes. It is commonly used, and you can buy these general air filters by clicking below.



What needs to do if your standard air filter doesn’t match your air filter’s dimension ?


You can use our custom tool to create the size if you can’ t see your size. If the standard size can’t be fit with you,you need to pick the specific dimension through our customer AC or  furnace filter.


Whether you are customized or use a standard size, we also can choose the different quality air filters, including the performance and rating, and whether you would like to deliver the air filter at recurring intervals.



Common size including 1 inch , 2inch ,and 4 inch standard size filters.


If our standard size air filters are not matched to the size you find, it is essential to find your brand on your whole hose replacement filter page or set a customized size filter.


Find the suitable size for yourself, and measure your air filter in the right way, you also can search it on our general filter size page, and maybe it is convenient for you to narrow the depth of your air filters , then begin your air filter search. 



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