Konrád Koller

This plugin helps you to fix any missing thumbnail issue in a fairly short time. The only thing you need to do is just few simple click and the plugin does the rest. It can be really helpful if you have thousands of images in your database.
You can regenerate thumbnails for each single image in your database or you can simply select those you really want to update. If you choose a post or page the plugin will regenerate thumbnails for each related images. You can choose from the following methods:
<ul>
<li>Regenerate thumbnails for all images in the database.</li>
<li>Bulk action in post liste: You can choose which one to update by checking the checkboxes.</li>
<li>Media library items: Move your mouse over the chosen image(s) and click on “Regenerate thumbnails” link.</li>
<li>Post editor: click on “Regenerate thumbnails” button which is next to “Add media” button. (Off by default)</li>
</ul>
Furthermore you can add your own thumbnails sizes, change default JPG compression rate and mass regenerate thumbnails. The best thing about this plugin is that you can use it with custom post types as well.

ONet Regenerate Thumbnails

Doesnt have 4.4.1 bulk generation support. But you can generate thumbnails one by one.



Doesnt have 4.4.1 support completely

Fix missing thumbnails in no time with few easy clicks. The plugin does the hard work.

Jordy Meow

Displays the metadata information in the Media Library. Regenerates the metadata and thumbnails even if they exist. This plugin is really useful when the metadata is broken. This is an extremely light plugin.
I am using this tool for debugging many installs and decided to make it available here. Try it, discuss it. Remarks are very welcome 🙂

Media Meta & Force Regenerate

No review for it yet, and probably need to be tried and reviewed by more. It does things Regenerate Thumbnails do not, it actually force regenerate the thumbnails, the metadata associated with it, and also visually display the content of this meta.

This plugin works

Displays the metadata information in the Media Library. Regenerates the metadata and thumbnails even if they exist.

ONet Regenerate Thumbnails vs Media Meta & Force Regenerate