This plugin hasn’t been tested with the latest 3 major releases of WordPress. It may no longer be maintained or supported and may have compatibility issues when used with more recent versions of WordPress.

Simple Matted Thumbnails


WordPress has two formats for thumbnails, they are either proportional or cropped. Proportional thumbnails don’t have a consistent size and
cropped thumbnails lose portions of the image. Neither of these options are optimal for images such as e-commerce product images that are
arranged in a grid or any other layout where exact size is required.

This plugin adds a third format, “Matted”. A matted thumbnail is the exact size requested like a cropped thumbnail.
The difference is that instead of taking away part of the image, a mat, similar to the physical cardboard mats used with photographs, is placed around it.
Images may be reduced in size but are never enlarged. The image is centered in the thumbnail box with the mat color as the background for the box.


  1. Upload the simple-matted-thumbnails folder to the /wp-content/plugins/ folder
  2. Activate the plugin through the ‘Plugins’ menu in the WordPress Admin


Where are the Settings

Login as admin and go to the settings. Click the Matted Thumbnails link. You can change the colour of the mat and which
thumbnail sizes are to be matted.

How do set I the mat’s background colour

The background colour can be set using the settings menu. The colour picker is the standard WordPress colour picker. If using an old version of WordPress
or with JavaScript disabled, you can set a hexadecimal RGB value similar to those used in CSS.

How do I apply this to specific thumbnail sizes

You can select the sizes by checking their name in the settings.

Matting is only applied to those sizes selected. Selecting a thumbnail size will override the crop setting. Thumbnail sizes that include the default
height or width of 9999 can not be matted.

What is the extra matting

This is space in the thumbnail box that is reserved for matting in addition to any needed to accommodate the image. The extra matting is placed on either both
top and bottom or both left and right sides.

How do I rebuild the thumbnails

After changing thumbnail settings, any new images will get the new thumbnail sizes and format, but existing images will not. There are several plugins that allow
the administrator to regenerate the thumbnails. Two popular plugins are “Regenerate Thumbnails” and “Force Regenerate Thumbnails”. Note that using either of
these will destroy existing thumbnails, so a backup is recommended.

What happens if I add a new thumbnail size

This plugin will not apply to new sizes unless you select them in the admin settings.


November 10, 2018
Finaly i found a solution to have a perfect aligned default wordpress gallery 🙂
Read all 6 reviews

Contributors & Developers

“Simple Matted Thumbnails” is open source software. The following people have contributed to this plugin.



Version 1.01

Fixed bug in admin that produces error message when debug enabled

Version 1.0

Plugin forked from the letterbox-thumbnails plugin.

Control added to select which thumbnail sizes to mat. The colour picker uses the WordPress Iris based colour picker introduced in WP 3.5