What It Does
Image Manager gives you full visibility and control over WordPress image sizes. It lists every registered size (core defaults, theme-added, plugin-added, and your custom sizes), lets you disable any size to prevent future generation, and supports creating new custom sizes. You can regenerate thumbnails for a specific size across your entire media library, view per-size disk usage stats, and clean up orphaned image files.
Features
- Lists all registered image sizes with dimensions and crop settings — defaults (thumbnail, medium, medium_large, large), theme/plugin sizes, and custom sizes
- Toggle any image size on/off — disabled sizes are skipped during future uploads
- Create custom image sizes with name, width, height, and crop mode
- Edit dimensions of default WordPress sizes and custom sizes (theme/plugin sizes are read-only)
- Delete custom sizes with optional automatic cleanup of generated files via WP-Cron
- Regenerate thumbnails for a specific size across all images in the media library
- Per-size statistics: usage count (how many images have this size) and total disk usage
- Media attachment detail overlay shows generated, missing, and disabled sizes for each image
- Per-image cleanup action to regenerate missing sizes and remove disabled ones
- Navigation links in admin bar and contextual help tab on Media Library, Media Settings, and Image Manager pages
How to Use
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Open Image Manager
Go to WP Multitool > Image Sizes in the admin menu.
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Review registered sizes
The table shows all image sizes grouped by type: WordPress defaults, theme/plugin sizes, and your custom sizes. Each row shows dimensions, crop setting, and whether it is active or disabled.
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Disable an unused size
Toggle the switch next to any size you do not need. Disabled sizes will not be generated for future uploads. Existing thumbnails are not deleted automatically.
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Create a custom size
Use the "Add New Size" form to define a name, width, height, and crop mode. The size is registered immediately and will be generated on future uploads.
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Regenerate thumbnails
Click "Regenerate" next to any size to generate that specific thumbnail for all existing images. This can take a while for large libraries — the process runs synchronously.
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Check disk usage
Click "Stats" on any size to see how many images use it and total disk space consumed.
Settings
| Setting | Default | Description |
|---|---|---|
| Enabled/Disabled Sizes | All sizes enabled |
Stored in wpmultitool_enabled_image_sizes option. Lists sizes that are disabled (despite the option name). |
| Custom Sizes | None |
Stored in wpmultitool_custom_image_sizes option. Array of custom size definitions (name, width, height, crop). |
FAQ
Will disabling an image size delete existing thumbnails?
No. Disabling a size only prevents it from being generated on future uploads. Existing thumbnails remain on disk. To remove them, delete the custom size (which schedules cleanup) or use the per-image cleanup action.
Will regenerating thumbnails delete my original images?
No. Only the specific thumbnail size is regenerated. Original uploaded images are never modified or deleted.
Can I edit theme or plugin image sizes?
You can disable them (prevent generation), but you cannot change their dimensions. Only WordPress default sizes and custom sizes you created can be edited.
How long does bulk regeneration take?
It depends on your media library size. Roughly 100 images takes about 1 minute, 1,000 images about 10 minutes. The process runs in a single AJAX request, so very large libraries may hit timeout limits.
What sizes does WordPress create by default?
WordPress registers four default sizes: thumbnail (150x150 cropped), medium (300x300), medium_large (768x0), and large (1024x1024). Themes and plugins often add more.
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