Custom Air Filters
Not able to find your filter size in the standard size list? Build your custom filter here!
Simply measure the length and width of your current filter using a tape measure and choose the closest whole number +/- 1/4”, and then choose the closest fraction +/-1/3”.
It is important to measure your filters correctly because custom filters use ‘actual’ sizing for the length and width and are not undercut like standard size filters. Although, custom and standard filters both use standard depths with an undercut, as shown below.
Depth Options:
1” = ¾”
2” = 1 ¾”
4” = 3 ¾”
Unsure about your sizing? Call our filter experts for assistance.
*Custom size filters require 10 working days to manufacture.
*Custom MERV 13 pleated filters require a 6-8 weeks to manufacture.
*Custom filters are nonreturnable and nonrefundable.
View our standard size list, which includes our nominal and actual sizes.
1" Stock Pleated Filter Sizes
| Nominal Size | Actual Size |
| 10 X 10 X 1 | 9-1/2 X 9-1/2 X 3/4 |
| 10 X 20 X 1 | 9-1/2 X 19-1/2 X 3/4 |
| 10 X 24 X 1 | 9-1/2 X 23-1/2 X 3/4 |
| 10 X 30 X 1 | 9-3/4 X 29-3/4 X 3/4 |
| 10 X 36 X 1 | 9-3/4 X 35-3/4 X 3/4 |
| 12 X 12 X 1 | 11-3/4 X 11-3/4 X 3/4 |
| 12 X 16 X 1 | 11-3/4 X 15-3/4 X 3/4 |
| 12 X 20 X 1 | 11-1/2 X 19-1/2 X 3/4 |
| 12 X 24 X 1 | 11-3/4 X 23-12 X 3/4 |
| 12 X 30 X 1 | 11-7/8 X 29-7/8 X 3/4 |
| 12 X 36 X 1 | 11-3/4 X 35-3/4 X 3/4 |
| 14 X 14 X 1 | 13-3/4 X 13-3/4 X 3/4 |
| 14 X 18 X 1 | 13-3/4 X 17-3/4 X 3/4 |
| 14 X 20 X 1 | 13-1/2 X 19-1/2 X 3/4 |
| 14 X 24 X 1 | 13-3/4 X 23-3/4 X 3/4 |
| 14 X 25 X 1 | 13-1/2 X 24-1/2 X 3/4 |
| 14 X 30 X 1 | 13-7/8 X 29-7/8 X 3/4 |
| 15 X 20 X 1 | 14-1/2 X 19-1/2 X 3/4 |
| 16 X 16 X 1 | 15-3/4 X 15-3/4 X 3/4 |
| 16 X 20 X 1 | 15-1/2 X 19-1/2 X 3/4 |
| 16 X 24 X 1 | 15-1/2 X 23-1/2 X 3/4 |
| 16 X 25 X 1 | 15-1/2 X 24-1/2 X 3/4 |
| 16 X 30 X 1 | 15-5/8 X 29-5/8 X 3/4 |
| 16 X 36 X 1 | 15-3/4 X 35-3/4 X 3/4 |
| 18 X 18 X 1 | 17-3/4 X 17-3/4 X 3/4 |
| 18 X 20 X 1 | 17-1/2 X 19-1/2 X 3/4 |
| 18 X 24 X 1 | 17-1/2 X 23-1/2 X 3/4 |
| 18 X 25 X 1 | 17-1/2 X 24-1/2 X 3/4 |
| 18 X 30 X 1 | 17-3/4 X 29-3/4 X 3/4 |
| 18 X 36 X 1 | 17-3/4 X 35-3/4 X 3/4 |
| 20 X 20 X 1 | 19-1/2 X 19-1/2 X 3/4 |
| 20 X 24 X 1 | 19-1/2 X 23-1/2 X 3/4 |
| 20 X 25 X 1 | 19-1/2 X 24-1/2 X 3/4 |
| 20 X 30 X 1 | 19-3/4 X 29-3/4 X 3/4 |
| 20 X 36 X 1 | 19-3/4 X 35-3/4 X 3/4 |
| 22 X 22 X 1 | 21-3/4 X 21-3/4 X 3/4 |
| 22 X 24 x 1 | 21-3/4 X 23-3/4 X 3/4 |
| 24 X 24 X 1 | 23-1/2 X 23-1/2 X 3/4 |
| 24 X 36 X 1 | 23-3/4 X 35-3/4 X 3/4 |
| 25 X 25 X 1 | 24-1/2 X 24-1/2 X 3/4 |
| 25 X 32 X 1 | 24-3/4 X 31-3/4 X 3/4 |
2" Stock Pleated Filter Sizes
| Nominal Size | Actual Size |
| 12 X 12 X 2 | 11-3/4 X 11-3/4 X 1-3/4 |
| 12 X 20 X 2 | 11-1/2 X 19-1/2 X 1-3/4 |
| 12 X 24 X 2 | 11-3/8 X 23-3/8 X 1-3/4 |
| 14 X 20 X 2 | 13-1/2 X 19-1/2 X 1-3/4 |
| 14 X 25 X 2 | 13-1/2 X 24-1/2 X 1-3/4 |
| 15 X 20 X 2 | 14-1/2 X 19-1/2 X 1-3/4 |
| 16 X 16 X 2 | 15-3/4 X 15-3/4 X 1-3/4 |
| 16 X 20 X 2 | 15-1/2 X 19-1/2 X 1-3/4 |
| 16 X 24 X 2 | 15-3/8 X 23-3/8 X 1-3/4 |
| 16 X 25 X 2 | 15-1/2 X 24-1/2 X 1-3/4 |
| 18 X 18 X 2 | 17-3/4 X 17-3/4 X 1-3/4 |
| 18 X 24 X 2 | 17-3/8 X 23-3/8 X 1-3/4 |
| 20 X 20 X 2 | 19-1/2 X 19-1/2 X 1-3/4 |
| 20 X 24 X 2 | 19-3/8 X 23-3/8 X 1-3/4 |
| 20 X 25 X 2 | 19-1/2 X 24-1/2 X 1-3/4 |
| 20 X 30 X 2 | 19-3/4 X 29-3/4 X 1-3/4 |
| 24 X 24 X 2 | 23-3/8 X 23-3/8 X 1-3/4 |
| 25 X 25 X 2 | 24-1/2 X 24-1/2 X 1-3/4 |
4" Stock Pleated Filter Sizes
| Nominal Size | Actual Size |
| 12 X 24 X 4 | 11-3/8 X 23-3/8 X 3-3/4 |
| 16 X 20 X 4 | 15-1/2 X 19-1/2 X 3-3/4 |
| 16 X 25 X 4 | 15-1/2 X 24-1/2 X 3-3/4 |
| 18 X 24 X 4 | 17-3/8 X 23-3/8 X 3-3/4 |
| 20 X 20 X 4 | 19-1/2 X 19-1/2 X 3-3/4 |
| 20 X 24 X 4 | 19-3/8 X 23-3/8 X 3-3/4 |
| 20 X 25 X 4 | 19-1/2 X 24-1/2 X 3-3/4 |
| 24 X 24 X 4 | 23-3/8 X 23-3/8 X 3-3/4 |
Custom Air Filter Instructions
Air Filters Inc. is committed to providing a "one-stop shop" for all of your air filtration requirements. As a manufacturer, we are uniquely positioned to custom make any and all types of air filters.If any length, width, or depth dimension is a:
a. Whole number, the tolerance will be within +/- 1/4".
b. Fraction, the tolerance will be within +/- 1/8".
If unsure about your sizing, call our experts for assistance.Custom size filters require 10 working days to manufacture.
CUSTOM FILTERS ARE NONRETURNABLE.