WebP Converter for Joomla

WebP Converter is a lightweight Joomla system plugin that automatically converts newly uploaded PNG and JPG images to WebP format. By reducing image file sizes at upload time, it improves page speed, Core Web Vitals, and overall website performance without changing your existing workflow.

The plugin integrates directly with Joomla’s Media Manager and works reliably in subfolders, making it a safe and practical solution for both new and existing websites.

Key Benefits

• Significant image size reduction
• WebP images are typically 30–80% smaller than PNG and JPG, resulting in faster page loads and reduced bandwidth usage.
• Improved Core Web Vitals and SEO
• Smaller images help improve metrics such as LCP and PageSpeed scores, contributing to better search engine visibility.
• Fully automatic workflow
• Upload images as usual via the Media Manager. Conversion happens automatically in the background.
• Safe for live websites
• Only new uploads are processed. Existing images are never modified.
• Works in Media Manager subfolders
• Images uploaded to any folder inside /images are converted correctly.
• Joomla-native and lightweight
• No external services, no cron jobs, no database tables, and no performance overhead.
• Compatible with Joomla 5 and Joomla 6
• Built using modern Joomla best practices and tested on current Joomla versions.

Main Features

Automatic WebP Conversion
PNG and JPG images are converted to WebP immediately after upload via the Joomla Media Manager.

Quality Control
Set the WebP quality level to balance compression and visual quality according to your project needs.

Original File Handling
Choose whether to keep the original PNG or JPG file, or remove it after successful conversion.

Folder-Aware Processing
The plugin respects Joomla’s folder structure and creates WebP files in the same directory as the original image.

Server-Based Conversion
Uses native PHP image libraries for reliable, fast conversion without third-party dependencies.

Minimal Footprint
No logs, no background processes, and no unnecessary complexity. The plugin runs only when an image is uploaded.

Ideal For

• Joomla websites that need faster loading images without manual optimization
• Agencies managing multiple Joomla projects
• Performance-focused sites aiming to improve Core Web Vitals
• Developers who want a clean, predictable, Joomla-native solution

WebPconverter — Changelog

1.2.3 — July 2026

Changes since 1.0.

Changed

• Upload detection now hooks Joomla's onContentAfterSave event directly (context com_media.file) instead of scanning /images for recently modified files. Removes false triggers from unrelated Media Manager actions (delete, rename, create folder) and prevents simultaneous uploads by different users from cross-converting each other's files.
• Conversion runs synchronously as part of the upload request, so the Media Manager grid can refresh reliably right after upload instead of racing a background job.

Added

• Imagick support: the "Conversion library" setting (Auto Detect / GD / Imagick) now actually applies. Auto Detect prefers GD and falls back to Imagick automatically on hosts where GD lacks WebP support.
• EXIF orientation is preserved during conversion — photos from phones and cameras no longer end up rotated incorrectly.
• Conversion failures (no WebP-capable library available) are now logged to administrator/logs/plg_system_webpconverter.php and shown as an admin warning, instead of failing silently.
• The Media Manager grid auto-refreshes after upload to show the converted file immediately.

Fixed

• Corrected Joomla's own upload response so it no longer references the original file after it's been deleted — this previously caused a "File or Folder not found" notice in the Media Manager right after upload when "Keep original" was off.

Unchanged (by design)

• "Update references" stays reserved for future use — rewriting file references across content and custom fields is a larger, separate feature.
• Still JPG/PNG only; animated GIFs are intentionally not converted (would be flattened to a static frame).1
• No bulk-convert for existing images — conversion still triggers on new uploads only.

Compatibility

Joomla 5.x and 6.x. No settings changes required for existing installs —
upgrades in place via the Joomla installer.