Thumbnail Manager

Thumbnail Manager helps you take back disk space from oversized Media Libraries.

What it does
– Prune Files: Select the image sizes you want to KEEP. The plugin scans your /uploads/ folder and targets all non-selected registered sizes for removal. It shows a dry-run summary first, then lets you delete in batches with a live progress bar.
– Orphan discovery: Finds on-disk files that match -WxH patterns (including .jpg.webp, .bak.jpg, retina @2x, and duplicate -1 suffixes) even if those sizes are no longer registered. Aggressively deletes any -WxH files that don’t exactly match the sizes you chose to keep (use with care).
– Subfolder scope: Limit scans to a specific year/month inside uploads/ for faster, safer runs on large libraries.
– Thumbnail Sizes: Choose which sizes should be generated for future uploads. Disabled sizes won’t be created at upload time (and are hidden from size pickers).

What it doesn’t do
– It does not regenerate thumbnails. Use a regeneration plugin if you need to rebuild sizes after changing settings.
– It never deletes original full-size images.

Who is it for?
Site owners, editors, and developers who’ve accumulated many custom image sizes (themes, page builders, sliders) and want to reduce storage bloat safely.

Features

• Two-tab UI: Prune Files & Thumbnail Sizes
• Dry-run mode with sample matches before any deletion
• AJAX progress bar and batch deletes to avoid timeouts
• Orphan -WxH discovery report and delete found dimensions
• Limit to subfolder (All, year, or year/month)
• Disable sizes for future uploads (does not unregister core sizes; simply prevents generation)
• Hides disabled sizes from Media size dropdowns (optional filter)
• Works per-site on single and multisite (run on each site as needed)

Usage

Prune Files

1. In the table, check the sizes you want to KEEP (e.g., thumbnail, medium, large, and optionally medium_large).
2. (Optional) Choose a subfolder (e.g., 2024/11) for a quicker, safer trial run.
3. Make Orphan discovery ON to see a report or do a deletion of found dimensions.
4. Click Run with Dry-run selected to preview matches.
5. Review results → switch to Delete when you’re confident.

Tip: Enable Orphan discovery only when you want to remove any extra -WxH sizes not exactly matching your KEEP list (great for cleaning legacy sizes like -1200x860 or .bak.jpg files).

Thumbnail Sizes

1. Uncheck any sizes you no longer want generated for future uploads.
2. Click Save changes.
   (This prevents those sizes from being created going forward; existing files are unaffected until you prune them in Prune Files Tab.)

Technical Notes

• Prevent generation via: intermediate_image_sizes_advanced (removes disabled sizes at upload time).
• Optionally hide in UI via: image_size_names_choose and reduce the base list via intermediate_image_sizes.
• Auto-scaled big image can be disabled with big_image_size_threshold if desired (not enabled by default).
• Requires capability manage_options.

Privacy

This plugin does not collect personal data or send data to external services. It only reads and modifies files within your /uploads/ directory based on your actions.

1. Upload the plugin folder to /wp-content/plugins/ or install via the Plugins screen.
2. Activate the plugin.
3. Go to Tools → Prune Thumbnails.

1. 

   Prune Files tab with size checkboxes, subfolder select, and progress bar.

2. 

   Thumbnail Sizes tab to disable sizes for future uploads.

1.0.1 (Dec 3, 2025)

• Added full translation support for all admin-facing text strings using the thumbnail-manager text domain.
• Improved default behavior for the “Keep” list in Prune Files:
• Updated admin UI labels and notices to support localization and internationalized formatting.
• Refined pattern-matching text for size notes to support correct translation formatting.
• Improved accessibility and consistency across the Prune Thumbnails and Thumbnail Sizes tabs.

1.0 (Oct 5, 2025)

• Initial release.
• Prune Files: Dry-run/report, batch deletion with progress, subfolder scope.
• Orphan -WxH discovery; optional Strict mode for unmatched dims.
• Thumbnail Sizes: disable generation for future uploads.