Rafał Dziewa

<p>DZIEWA Media Converter creates sidecar <code>.avif</code> and <code>.webp</code> files next to your originals (no replacement of JPG/PNG in the Media Library). On the front end it can rewrite <code><img></code> tags to <code><picture></code> so browsers pick AVIF/WebP when available. The plugin is <strong>entirely free to use</strong> — no license fees, no pro version, and no paid add-ons.</p>
<h4>How it works</h4>
<p>The plugin generates additional AVIF and/or WebP files beside every JPEG/PNG you upload. Originals are never touched or replaced — they remain in the Media Library and on disk as a safe fallback. The optional content filter detects <code><img></code> tags in your post content and wraps them in <code><picture></code> so modern browsers download the smaller AVIF/WebP version, while older browsers transparently fall back to JPG/PNG.</p>
<h4>Conversion</h4>
<ul>
<li><strong>AVIF + WebP, AVIF-only or WebP-only</strong> output modes. AVIF requires PHP GD built with AVIF support; the plugin auto-detects this on activation and gracefully falls back to WebP-only when AVIF is unavailable.</li>
<li><strong>Configurable quality</strong> per format (independent AVIF and WebP quality sliders in settings).</li>
<li><strong>Automatic conversion on upload</strong> — new attachments are converted in the background via WP-Cron or Action Scheduler (when available), so the upload screen never blocks.</li>
<li><strong>Intermediate sizes (thumbnails)</strong> are optionally converted too, so every srcset variant has its own AVIF/WebP sidecar.</li>
</ul>
<h4>Existing media</h4>
<ul>
<li><strong>Background queue</strong> processes already-uploaded images in configurable batches (default 20 files per run, range 5–200). You can scope the queue to a single uploads subfolder and/or a date range to avoid scanning the whole library at once.</li>
<li><strong>Bulk action in the Media Library</strong> — select images and run <strong>Convert to AVIF/WebP</strong> from the bulk menu.</li>
<li><strong>Per-attachment button</strong> — Media Library list, attachment edit screen and media modal each show a <strong>Convert to AVIF/WebP</strong> button next to live savings stats (before/after size, percentage saved per format).</li>
</ul>
<h4>Front end (content rewriting)</h4>
<ul>
<li>Optional <code><picture></code> rewrite in <code>the_content</code> and post thumbnails — browsers automatically pick the lightest format they support.</li>
<li>Lookup of attachment IDs from URLs is cached in the WordPress object cache (Redis/Memcached when available) and memoised per request, so heavy pages with many images stay fast.</li>
</ul>
<h4>Tools & admin UI</h4>
<ul>
<li><strong>Cleanup tool</strong> — remove old generated <code>.avif</code> / <code>.webp</code> sidecars by age (30/60/90/120 days) and folder scope, with a per-folder picker.</li>
<li><strong>Admin bar download</strong> — optional link on singular posts/pages to download the original JPG/PNG of the featured image (useful for social platforms that don’t accept AVIF/WebP).</li>
<li><strong>Event log</strong> — last 100 events (errors, conversions, queue runs) visible on the settings page.</li>
<li><strong>Three-option uninstall dialog</strong> — when removing the plugin you choose between <em>Cancel</em>, <em>Remove (keep generated files)</em> or <em>Remove and delete files</em>.</li>
</ul>
<h4>Privacy & dependencies</h4>
<ul>
<li>No external services, no remote calls, no tracking. Everything runs on your own server.</li>
<li>Requires PHP 8.3+ and PHP GD with WebP support (<code>imagewebp</code>). AVIF is optional.</li>
<li>Fully translated to Polish; English source strings ready for further translations via GlotPress.</li>
</ul>


DZIEWA Media Converter — AVIF + WebP

Converts JPEG/PNG to AVIF and WebP; rewrites content to <picture> with JPG/PNG fallback. Completely free, no paid version.

Adam Silverstein

Google

<p>Specify the default image format used for sub-sized images generated by WordPress.</p>
<h3>Technical Notes</h3>
<ul>
<li>Requires PHP 5.6+.</li>
<li>Requires WordPress 5.8+.</li>
<li>Issues and Pull requests welcome on the GitHub repository: https://github.com/adamsilverstein/wordpress-modern-images.</li>
</ul>


DZIEWA Media Converter — AVIF + WebP vs Modern Images WP