AVIF & WebP conversion.
AI alt text built in.
Cetus converts your media library to next-gen formats and writes descriptive alt text with AI - Google Gemini or OpenAI, using your own key. Orphan scanner, asynchronous bulk processor and WP-Cron background jobs included. Your original files are never touched.
See what it does ↓Everything your media library needs.
Conversion, AI accessibility and library housekeeping in one plugin. Use what you need, disable what you don't - no code required.
Next-gen conversion
Creates optimised AVIF or WebP copies alongside your originals using Imagick, with an automatic GD fallback. Your JPG/PNG/GIF source files are never deleted.
Smart format selection
Automatic mode probes the server and picks AVIF when it's supported, WebP otherwise. You can also force a single format or disable conversion entirely.
Auto-convert on upload
Optionally convert every new image the moment it lands in the media library, so freshly uploaded media is already optimised without a second pass.
AI-powered Alt Text
Sends images to Google Gemini or OpenAI with your own API key and saves the description as native _wp_attachment_image_alt. Automatic provider fallback on quota errors (HTTP 429).
Asynchronous bulk processor
Processes the library in AJAX batches of five images with a real-time progress bar, speed, ETA and Pause / Stop controls. Built to survive shared-hosting timeouts.
Orphan file scanner
Finds images sitting on disk that aren't registered in the WordPress database and optimises them through a tick-based system that handles 2,000+ files without timing out.
Background processing
Hands the queue to WP-Cron and converts images five at a time every five minutes - no need to keep a browser tab open while a large library is processed.
Automatic URL rewriting
Swaps JPG/PNG URLs for their AVIF/WebP equivalents on the frontend. If an optimised file is missing, it silently rolls back to the original - no 404s, no black squares.
Opt-in, privacy-first
Crash telemetry is opt-in and disabled by default. An optional switch removes all plugin data on uninstall - nothing is collected or deleted unless you ask for it.
Install. Convert. Ship lighter.
Every conversion adds a new file next to your original - the source image is never overwritten or deleted, and the database is never rewritten. Deactivate the plugin and your originals stay exactly where they were.
Built to SkapaCraft standards.
Now available on WordPress.org.
Install it directly from your WordPress dashboard, or grab it from the plugin directory.
Get it on WordPress.org