Thumbnail Manager
Regenerate WordPress thumbnails, control image sizes, and safely clean generated files with resumable, review-first jobs.
The facts
- Rating
- 5★ from 1
- Active installs
- 100+
- Price
- Free
- Last updated
- 29 Aug 2026
- Added
- Oct 2025
- Requires WP
- 6.3
- Tested up to
- WP 7.0.4
- Requires PHP
- 7.4
- Downloads
- 1,360
Our analysis
AI-assistedThumbnail Manager is a WordPress plugin designed to help you manage image sizes within your Media Library. It allows you to regenerate image sizes, prevent thumbnail bloat, and review files before deletion. This is particularly useful after changing themes, adjusting WooCommerce settings, or when dealing with a long-running Media Library that may have obsolete image sizes.
The plugin runs large operations as persistent jobs, which can continue in batches even if there is a page reload or network interruption. You can review and decide which image sizes to keep, generate only missing sizes, or force regeneration of selected attachments. It does not compress images or convert them to different formats, and it operates locally without collecting personal data.
Best for: This plugin suits WordPress users who need to manage image sizes effectively in their Media Library.
What it does well
- ✓Helps regenerate WordPress image sizes
- ✓Prevents future thumbnail bloat
- ✓Allows review of files before cleanup
- ✓Runs large operations as persistent jobs
- ✓Does not collect or transmit personal data
Where it falls short
- •Does not compress images or convert formats
- •No option to unregister sizes from themes or plugins
- •Missing scan evidence leaves current size settings unchanged
Verdict
Thumbnail Manager offers a structured approach to image size management, making it useful for users with extensive media libraries. However, it has limitations in terms of image compression and format conversion.
From the developer
YoOhw Studio's own description of Thumbnail Manager, lightly tidied.
Product page | Documentation | Support
Thumbnail Manager helps regenerate WordPress image sizes, prevent future thumbnail bloat, and review generated files before cleanup. Use it after changing themes or WooCommerce image settings, migrating a site, or finding obsolete sizes in a long-running Media Library.
Large operations run as persistent, bounded jobs. They continue in batches, survive a page reload or network interruption, and use scoped processing where the workflow supports it.
Thumbnail control and regeneration
- Review every registered image size and decide which sizes WordPress should generate for future uploads.
- Generate only missing sizes or force-regenerate selected image attachments.
- Regenerate all media, current-year images, one uploads folder, or specific image attachments.
- Review conservative keep recommendations with explicit evidence and confidence based on protected size policies, attachment metadata, and common content references.
- Resume or cancel persistent jobs and review recent job results and per-item errors.
Review-first cleanup
Prune Files separates discovery from deletion:
- Choose the image sizes to keep.
- Scan all uploads or selected year and month folders.
- Review the immutable, hashed manifest and estimated storage total.
- Explicitly approve the reviewed manifest.
- Delete only those approved generated files in resumable batches.
Original full-size uploads are protected. Candidate paths are validated inside the WordPress uploads directory, and attachment metadata is updated when a generated size is removed.
Metadata-backed legacy sizes can be included in the review. Disk-only files that match a -WIDTHxHEIGHT pattern but cannot be mapped reliably to attachment metadata are reported and skipped by default.
Scope
Thumbnail Manager controls image-size generation, regeneration, and cleanup. It does not compress images, convert them to WebP or AVIF, configure a CDN, offload media, or unregister a size from the theme or plugin that originally registered it.
Recommendations are an informed starting point, not proof that a size is used or unused. Missing scan evidence leaves the current size setting unchanged. Verify the sizes used by the active theme, plugins, WooCommerce templates, and custom code before disabling generation or approving deletion.
Privacy
Thumbnail Manager does not collect, store, or transmit personal data to external services. Thumbnail analysis, regeneration, recommendations, and cleanup run locally on the WordPress site.
Persistent settings, job history, audit/recovery rows, and derived media-reference data remain in the site’s database after deactivation or plugin deletion. Browser-local job tokens may also remain in the administrator’s browser. Review and remove retained data separately when required by the site’s privacy policy.