York IE – WebP on Upload

York IE – WebP on Upload plugin automatically converts JPEG, PNG, and static GIF images to WebP format while uploading them to the WordPress media library. The plugin replaces the original files on disk and converts every registered image size generated by WordPress.

This helps reduce image file sizes and improve page load performance without requiring a third-party image optimization service.

Features

• Automatic WebP conversion on media upload
• Replaces the original image file with the WebP version
• Converts all generated image sizes (thumbnail, medium, large, and custom sizes)
• Per-format settings for JPEG, PNG, and GIF
• Manual Convert to WebP button in the attachment details popup
• Bulk Convert to WebP action in the Media Library list view
• Skips animated GIF and SVG files
• Uses PHP GD (imagewebp) — no external API required

Requirements

• PHP GD extension with WebP support (imagewebp())
• WordPress 6.0 or later

How it works

1. A user uploads an image to the Media Library.
2. The plugin checks whether the format is enabled in settings.
3. GD converts the uploaded file and all generated sizes to WebP.
4. Original files are replaced with .webp versions and attachment metadata is updated.

Developer filters

• yiewebpu_webp_quality — Adjust the WebP quality (0–100) used during conversion. Default is 82.