Katsushi Kawamori

<h4>Generate Thumbnails</h4>
<ul>
<li>Generate Thumbnails from all the images by asynchronous processing.</li>
<li>Generate Thumbnails from select the images by asynchronous processing.</li>
<li>If you are an administrator, it will generate thumbnails for all images, otherwise it will generate thumbnails for the images owned by each user.</li>
</ul>
<h4>The following plugin adds a function for generating thumbnails.</h4>
<ul>
<li>Select the thumbnails and functions to disable it. <a href="https://wordpress.org/plugins/disable-generate-thumbnails/" rel="ugc">Disable Generate Thumbnails</a></li>
<li>Specify the ratio of thumbnails generation. <a href="https://wordpress.org/plugins/ratio-thumbnails-size/" rel="ugc">Ratio Thumbnails Size</a></li>
</ul>
<h4>WP-CLI</h4>
<p>WP-CLI commands are available.<br />
* <code>wp bgth_cli mail</code> -> Send results via email.<br />
* <code>wp bgth_cli nomail</code> -> Do not send results by email.<br />
* <code>wp bgth_cli mail --uid=13</code> -> Process only specified User ID(13).<br />
* <code>wp bgth_cli mail --pid=12152</code> -> Process only specified Post ID(12152).</p>


Bulk Generate Thumbnails

YoOhw Studio

<p>Thumbnail Manager is a powerful tool to take full control over your WordPress image system.</p>
<p>Instead of letting themes and plugins generate dozens of unnecessary thumbnails, you can now:</p>
<ul>
<li><strong>Control which sizes are created</strong></li>
<li><strong>Remove unused thumbnails safely</strong></li>
<li><strong>Regenerate only what you actually need</strong></li>
</ul>
<p>All in one place.</p>
<h3>🚀 What it does</h3>
<p><strong>1. Regenerate Thumbnails (NEW)</strong><br />
– Regenerate thumbnails based on your current enabled sizes<br />
– Works in batches with progress tracking (no timeout issues)<br />
– Perfect after disabling unwanted sizes<br />
– Ensures your Media Library stays consistent and optimized</p>
<p><strong>2. Prune Unused Thumbnails</strong><br />
– Select sizes you want to <strong>KEEP</strong><br />
– Automatically detect and remove all other generated thumbnails<br />
– Supports:<br />
  – Registered sizes<br />
  – Orphan <code>-WxH</code> files<br />
  – <code>.webp</code>, <code>.bak</code>, <code>@2x</code>, <code>-1</code> variants</p>
<p><strong>3. Orphan File Discovery</strong><br />
– Detect leftover thumbnails no longer registered<br />
– Clean legacy sizes from old themes/plugins<br />
– Optional aggressive cleanup mode</p>
<p><strong>4. Disable Sizes for Future Uploads</strong><br />
– Prevent unnecessary thumbnails from being generated<br />
– Reduce storage usage going forward<br />
– Keeps your system lean and predictable</p>
<p><strong>5. Scoped Processing</strong><br />
– Limit operations to specific folders (year/month)<br />
– Safer testing on large Media Libraries</p>
<h3>❌ What it does NOT do</h3>
<ul>
<li>It <strong>does NOT delete original full-size images</strong></li>
<li>It <strong>does NOT modify image quality or compression</strong></li>
<li>It <strong>does NOT replace image optimization plugins</strong></li>
<li>It does not automatically run actions without your confirmation</li>
</ul>
<h3>🎯 Who is it for?</h3>
<ul>
<li>WooCommerce stores with heavy image usage</li>
<li>Sites using multiple themes/page builders</li>
<li>Developers cleaning legacy media bloat</li>
<li>Anyone hitting disk limits or slow backups</li>
</ul>
<h3>Features</h3>
<ul>
<li>3-tab UI: <strong>Regenerate</strong>, <strong>Prune Files</strong>, <strong>Thumbnail Sizes</strong></li>
<li>Batch processing with AJAX (no timeouts)</li>
<li>Dry-run preview before deletion</li>
<li>Smart orphan detection</li>
<li>Progress bars + live feedback</li>
<li>Future upload size control</li>
<li>Multisite compatible (run per site)</li>
</ul>
<h3>Usage</h3>
<h3>Regenerate (Recommended flow)</h3>
<ol>
<li>Go to <strong>Thumbnail Sizes</strong></li>
<li>Disable unwanted sizes</li>
<li>Click <strong>Save changes and run regenerate</strong></li>
<li>Let the system rebuild only the sizes you want</li>
</ol>
<h3>Prune Files</h3>
<ol>
<li>Select sizes to <strong>KEEP</strong></li>
<li>Run <strong>Dry-run</strong> first</li>
<li>Review results</li>
<li>Switch to <strong>Delete</strong> and execute</li>
</ol>
<h3>Thumbnail Sizes</h3>
<ul>
<li>Enable/disable sizes for future uploads</li>
<li>Does NOT affect existing images until prune/regenerate is used</li>
</ul>
<h3>Technical Notes</h3>
<ul>
<li>Uses <code>intermediate_image_sizes_advanced</code> to control generation</li>
<li>Uses AJAX batching to avoid server timeout</li>
<li>Safe file targeting via pattern matching</li>
<li>Requires <code>manage_options</code> capability</li>
</ul>
<h3>Privacy</h3>
<p>This plugin does not collect or transmit any personal data.<br />
All operations are performed locally on your server.</p>


Thumbnail Manager

Clean, control, and regenerate thumbnails with precision — remove unused sizes, prevent bloat, and rebuild what matters.

Bulk Generate Thumbnails vs Thumbnail Manager