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.

WordPress.org

<p>This plugin adds WebP and AVIF support for media uploads within the WordPress application. By default, AVIF images will be generated if supported on the hosting server, otherwise WebP will be used as the output format. When both formats are available, the output format can be selected under <code>Settings > Media</code>. Modern images will be generated only for new uploads, pre-existing images will only converted to a modern format if images are regenerated. Images can be regenerated with a plugin like <a href="https://wordpress.org/plugins/regenerate-thumbnails/" rel="ugc">Regenerate Thumbnails</a> or via WP-CLI with the <code>wp media regenerate</code> <a href="https://developer.wordpress.org/cli/commands/media/regenerate/" rel="nofollow ugc">command</a>.</p>
<p>By default, only modern image format sub-sizes will be generated for JPEG or PNG uploads – only the original uploaded file will still exist as a JPEG/PNG image, generated image sizes will be WebP or AVIF files. To change this behavior, there is a checkbox in <code>Settings > Media</code> “Output fallback images” that – when checked – will result in the plugin generating both the original format as well as WebP or AVIF images for every sub-size (noting again that this will only affect newly uploaded images, i.e. after making said change).</p>
<p><em>This plugin was formerly known as WebP Uploads.</em></p>


Modern Image Formats


I love that it doesn't force you to generate all image sizes of the original format and avif, but just does the avif (or webp if you choose that). It would be really nice if it could rework old images, and maybe even modify the database to match. But still, excellent and should be installed first thing on all new WP sites in my opinion.


Easiest way to get AVIF images


Thanks for developing this plugin!It's my #1 plugin for image optimization!


So far so good!

Converts images to more modern formats such as WebP or AVIF during upload.

DZIEWA Media Converter — AVIF + WebP vs Modern Image Formats