Pipe9 Media Optimizer
Pipe9 Media Optimizer converts your uploaded images to WebP automatically — no batch jobs, no manual steps, no complex configuration. When a browser supports WebP (all modern browsers do), the optimized version is served instead of the original, reducing page weight by 25-35% on average with zero visible quality loss.
How it works:
When you upload an image to WordPress, the plugin creates a WebP copy and stores it alongside the original in uploads/pipe9-media-optimizer/webp/. When a visitor loads a page, the plugin detects browser support via the Accept header and serves the WebP version — either through server-level rewrite rules, HTML markup, or a lightweight PHP endpoint.
Key features:
- Automatic conversion on upload — JPEG, PNG, and static GIF images are converted to WebP as soon as they hit the media library. Animated GIFs are converted to animated WebP via gif2webp or Imagick (previously a Pro feature — now free!)
- Six serving strategies: Apache rewrite rules (zero PHP cost — the fastest option), HTML
<picture>wrapping (single buffer scan per page), Nginx config snippet (paste and go — includes theme image rules), PHP passthru endpoint (works on any server), WP Engine optimized mode, or conversion-only mode (no serving changes) - Theme image conversion — scans and converts images inside active theme directories
- Bulk conversion — convert your entire existing media library with one click, with a real-time progress bar
- Media Library integration — each image gets a format column showing WebP status, with per-image convert and remove actions
- Memory guard — automatically detects when an image is too large to convert without blowing through PHP's memory limit, and skips it gracefully
- Pluggable architecture — modules register themselves via WordPress hooks; the Pro add-on adds AVIF and animated format support through the same system
Pro add-on (separate purchase from pipe9.uk) adds: * Static AVIF conversion (JPEG/PNG/GIF → AVIF) — even smaller files than WebP * Animated AVIF conversion (animated GIF → animated AVIF via ffmpeg)