aiwatech

Every time you upload an image, WordPress doesn’t just store your file — it generates a separate cropped copy for every registered image size. A fresh install already creates three (thumbnail, medium, and large) on top of the original, so a single upload becomes four files on your server.
Themes and plugins add many more. A typical site might register hero, slider, product thumbnail, team member, and testimonial sizes — and WooCommerce adds several of its own. With six registered sizes, one upload turns into seven files, even when the page only ever displays one of them. The rest sit on disk doing nothing but consuming space.
Multiply that across hundreds of posts, pages, and products and the waste adds up fast: bloated storage, slower backups, and longer upload processing. It’s especially painful on WooCommerce sites, where uploading a single banner or hero image also generates the full set of product thumbnail sizes you’ll never use for that image.
WP Image Sizes fixes this by letting you decide which sizes WordPress is allowed to create.
<ul>
<li>Per post type control — Assign the exact image sizes that matter to each post type from a simple settings page. A slider post type might only need one large size; testimonials might only need a thumbnail.</li>
<li>Choose sizes at upload time — When you add media, the uploader shows the available sizes so you can pick what gets generated for that specific upload.</li>
<li>Disable thumbnails entirely — Skip generating any additional sizes for a post type or a single upload when you only need the original.</li>
<li>No lock-in — WP Image Sizes never caches or alters your files. Any images already generated stay intact, even if you deactivate or remove the plugin.</li>
</ul>
The result is a leaner media library, less wasted disk space, and a faster, lighter WordPress site.
<h3>PRO</h3>
The free plugin controls which sizes get generated on new uploads. WP Image Sizes Pro extends this to your existing media and adds automation:
<ul>
<li>Bulk Create Image Sizes — Generate selected image sizes for all existing images of a chosen post type. Perfect after registering a new size or switching themes.</li>
<li>Bulk Delete Image Sizes — Remove unwanted image size files from existing media to reclaim server space in one click.</li>
<li>Create Images on Runtime — Automatically generate a missing image size the moment it is first requested on the front end, instead of pre-creating every size.</li>
</ul>
<a href="https://aiwatech.com/product/wp-image-sizes-pro/" rel="nofollow ugc">Get WP Image Sizes Pro</a>

WP Image Sizes

Take control of the image sizes WordPress generates. Pick only the sizes you actually use, per post type, and reclaim wasted server space.

mansoormunib

Image Sizes in Admin Dashboard adds a read-only widget to the WordPress admin Dashboard that lists all currently registered image sizes.
Any size you register in your theme or plugin with <code>add_image_size()</code> is picked up automatically, alongside the built-in <code>thumbnail</code>, <code>medium</code>, <code>medium_large</code> and <code>large</code> sizes. Each row shows:
<ul>
<li>The image size name (human readable)</li>
<li>Width in pixels (— when unconstrained)</li>
<li>Height in pixels (— when unconstrained)</li>
<li>Crop mode (Cropped or Proportional)</li>
</ul>
This is handy when building a theme and you need a quick reference of the exact dimensions available to <code>the_post_thumbnail()</code> and the media library.
More detail on registering custom image sizes: https://developer.wordpress.org/reference/functions/add_image_size/

Image Sizes in Admin Dashboard

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Lists every registered image size — built-in and custom add_image_size() sizes — with width, height and crop mode in a Dashboard widget.

WP Image Sizes vs Image Sizes in Admin Dashboard