The Simple Image Sizes plugin is a simple, yet powerful WordPress plugin that helps to see what image sizes have been set, to set new image sizes and to (re)generate the image sizes.
WordPress offers effective functionality for developers to be able to use their own image sizes. The Simple Image Sizes plugin can either be used to tap into this functionality or be used in combination with image size-related functions.
The Simple Image Sizes WordPress plugin
Simple Image Sizes (version 3.2.1) is a free WordPress plugin created by Rahe. At the time of writing, it had over 100 000 active installs and an average rating of 4.5 out of 5 stars. Although the plugin hasn’t been updated for some time now, it still seems to work correctly on the latest version of WordPress (5.4.1).
The plugin is used for generating newly set image sizes. In addition to this, Simple Image Sizes also offers supportive functionality to the default image sizes set by WordPress, built-in image sizes set by other plugins and themes and additional image sizes set by developers.
Simple Image Sizes can be installed by simply typing its name in the search bar of the Add Plugins section. After its activation, its front end is incorporated into the WordPress Media Settings section (Dashboard -> Settings -> Media).
Using Simple Image Sizes to see what image sizes have been set
In addition to the default WordPress image sizes (i.e. Thumbnail size, Medium size and Large size), Simple Image Sizes will show built-in image sizes (set by other plugins and themes) and additional image sizes (set by the theme/plugin developer).
Using Simple Image Sizes to set new image sizes
By default, Simple Image Sizes also comes pre-installed with two template entries to set additional image sizes. These templates are called ‘1536×1536’ and ‘2048×2048’ and can be used to set custom image sizes by simply changing their dimensions and Public name before pressing the appropriate Update button. In addition to this, the extensive cropping options and Show in post insertion settings can also be set.
Note that these two image sizes are built-in image sizes defined by the Simple Image Sizes plugin. If Simple Image Sizes is deactivated/deleted, then they will not be available anymore. If the user intends to remove the Simple Image Sizes plugin (which is often done after old images have been regenerated) then they should be added to the (child) theme’s
functions.php file (see Using Simple Image Sizes to create PHP code below).
Using Simple Image Sizes to generate new images
This is where the Simple Image Sizes plugin shines the brightest. Unfortunately, images uploaded before a new image size has been defined will have to be (re)generated to add the new size. Simple Image Sizes will do that for you.
By scrolling down on the WordPress Media Settings section, the user will see the Thumbnail regeneration section of the Simple Image Sizes plugin. Here the user can decide exactly which images to regenerate/resize.
Options include by image public name and by post type. The user can simply make a selection and then press the Regenerate Thumbnails button at which Simple Image Sizes will start to go through the already uploaded images one by one. Unfortunately, Simple Image Sizes will not regenerate images that were already resized.
After the old images have been regenerated, WordPress will continue to regenerate new images each time they are being uploaded to the website. For this reason, Simple Image Sizes if often deactivated/deleted after old images have been updated.
Using Simple Image Sizes to create PHP code
The third handly feature of Simple Image Sizes is the ability to create PHP code for plugins/themes. This code is added to the (child) theme’s
functions.php file and will allow the Simple Image Sizes plugin to be removed in the future, but still have the image sizes active.
Unfortunately, this functionality is not complete. To be fully operational, WordPress needs image sizes to be added with the
add_image_size() function and the
image_size_names_choose() function. Simple Image Sizes will only generate the PHP code for adding additional image sizes with the