As I always like to work out a system and best practices, I started working with the media image size feature. If you are not familiar this feature will resize any images you upload into the media gallery. Then when you add an image to a post or page, you can select which size you want to display. This is a very helpful feature. The trouble is you only get three sizes, however, there are several plugins that can help you work with image sizes and regenerating these different sizes.
Working with WP media images can be divided into two sections.
This can be coded directly into the WordPress code or you can find a plugin to help you with it.
When you look at the plugins, they can be divided into 3 categories
Here are the plugins that I have found in each category
this is the one that show up on the admin bar.
This is the one that creates a whole bunch of default image sizes that can not be deleted in settings
When this plugin is added, Settings > Media will have a whole bunch of new thumbnail sizes.
I have used it on quite a few sites and it works great. Not entirely sure what the difference between “Regenerate Thumbnails” and “Force Regenerate Thumbnails” is but I think force regenerated thumbnails came along after.
How to use Force Regenerate Thumbnails
To Access Force Regenerate Thumbnails, in the admin backend go to: Tools > Force Regenerate Thumbnails
Once you click “Force Regenerate Thumbnails” you will see the main screen. On this screen, you can regenerate “All Thumbnails” or “Specific Thumbnails”.
If you click all thumbnails you are taken to a progress bar page, and if you have a lot of images, this can take some time.
If you want to selectively regenerate thumbnails, you are taken to the media manager page, her
The functionality can also be accessed in the media library page. Here you can mouse over the desired image and the hover action will show teh force regenerate thumbnails functionality.
There is also the option to bulk delete specific images. To do this, tick the box next to the images you want to work with and then in the Bulk Actions select box, select Force Regenerate Thumbnails.
As you can see Force Regenerate Images, is straightforward and easy to work with.
The main differences between Force Regenerate thumbnails and regenerate thumbnails
Developer of each
What are the different features
Regenerated Thumbnails Advanced
WP Plugin Directory: https://wordpress.org/plugins/regenerate-thumbnails-advanced/
This program will do both and seems full featured
When I installed it, it creates about a dozen different sizes of thumbnails. You have the ability to delete image sizes, but the settings would not take when I tried to delete the image sizes.
Steven Johnson, a WP Hosting Reviews senior editor, works from Atlanta and covers all things related to WordPress and Hosting. He graduated from Georgia Tech in Chemical Engineering, has managed hosting companies and now builds WordPress and Joomla Websites for small to medium companies full time.