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.

Darko G.

MegaOptim

<p>MegaOptim 2.0 is a WordPress image optimizer built around three goals:</p>
<ol>
<li><strong>Further compress existing WebP and AVIF images.</strong> Next-gen formats are already small — MegaOptim 2.0 squeezes more out of them while keeping originals intact.</li>
<li><strong>Convert old JPG, PNG, and GIF images to WebP or AVIF.</strong> Modernize your Media Library and serve next-gen formats to supported browsers, with the original file preserved as a fallback.</li>
<li><strong>Optimize old formats in place.</strong> Make JPEG and PNG smaller without changing the format — useful when you want savings but don’t want a next-gen conversion. GIF, WebP, and AVIF compression are available through MegaOptim Cloud.</li>
</ol>
<p>The plugin is <strong>free</strong> when you use the local method (GD or Imagick on your server). For smarter compression — including further optimization of existing WebP and AVIF files — add an API key and use <strong>MegaOptim Cloud</strong>, available for around <strong>$54 per year</strong> on <strong>unlimited sites</strong>.</p>
<h4>Why Use MegaOptim?</h4>
<ul>
<li>Further compress existing WebP and AVIF images for extra savings</li>
<li>Convert JPEG, PNG, and GIF images to WebP or AVIF</li>
<li>Optimize JPEG and PNG in place with no format change (GIF/WebP/AVIF compression via Cloud)</li>
<li>Bulk process the WordPress Media Library</li>
<li>Browse and process folders outside the Media Library</li>
<li>Free local processing or smarter MegaOptim Cloud compression</li>
<li>Automatically convert or compress newly uploaded images</li>
<li>Serve WebP and AVIF with Apache <code>.htaccess</code> or PHP passthru</li>
<li>Track background jobs with a built-in queue monitor</li>
<li>Restore compressed originals from backup or remove generated next-gen files</li>
<li>Optionally process retina images generated by WP Retina 2x / Perfect Images</li>
<li>Use WP-CLI for bulk conversion, stats, reset, logs, and queue tools</li>
</ul>
<h4>Free Local Processing or MegaOptim Cloud</h4>
<p>MegaOptim works without an API key. If your server has GD or Imagick, you can convert JPEG/PNG/GIF to WebP, generate AVIF where your server supports it, and compress JPEG and PNG entirely on your own server — free, forever. GIF, WebP, and AVIF compression are available via MegaOptim Cloud.</p>
<p>For noticeably better results — including further compression of existing WebP and AVIF images, smarter JPEG/PNG optimization, and broader AVIF support — add a MegaOptim API key. MegaOptim Cloud offloads processing from your server and costs just <strong>$54 per year</strong> for <strong>unlimited sites</strong>. Get an API key from <a href="https://app.megaoptim.com/" rel="noopener noreferrer nofollow ugc">the MegaOptim dashboard</a> and see plans at <a href="https://megaoptim.com/pricing/" rel="noopener noreferrer nofollow ugc">MegaOptim pricing</a>.</p>
<h4>What MegaOptim 2.0 Can Do</h4>
<ul>
<li>Next-gen optimization: Further compress existing WebP and AVIF images through MegaOptim Cloud</li>
<li>Convert mode: Generate WebP or AVIF versions from JPEG, PNG, and GIF images</li>
<li>Compress mode: Optimize original images in place (no format change) with local or smart cloud compression</li>
<li>Media Library view: Process individual images, selected images, or run bulk jobs across the library</li>
<li>File System view: Browse folders on your server and bulk-process images outside the Media Library</li>
<li>Upload automation: Automatically convert or compress new uploads in the background</li>
<li>Delivery settings: Choose Apache <code>.htaccess</code> rules or PHP passthru rewriting to serve WebP and AVIF</li>
<li>Queue monitor: Watch active jobs, progress, failures, and background processing state</li>
<li>Tools page: Run restore actions for compressed originals or remove generated WebP/AVIF derivatives</li>
<li>Restore support: Restore compressed images from backup and regenerate thumbnails</li>
<li>Logging and diagnostics: Use the built-in log viewer and queue statistics through WP-CLI</li>
<li>Retina support: Optionally process <code>@2x</code> images created by WP Retina 2x or Perfect Images</li>
</ul>
<h4>Originals Preserved</h4>
<p>MegaOptim 2.0 keeps your original uploads in place and generates next-gen derivatives alongside them. On the front end, MegaOptim serves the best format the visitor’s browser supports while keeping the original file available as a fallback.</p>
<h4>Migration From Older MegaOptim Versions</h4>
<p>MegaOptim 2.0 includes background migration for legacy settings and older attachment data. Existing users can upgrade and let MegaOptim migrate data in batches, with progress shown inside the admin UI while migration is running.</p>


MegaOptim Image Optimizer – Optimize WebP & AVIF, Compress Images, Convert to WebP & AVIF

Further compress WebP and AVIF images, convert old JPG, PNG, and GIF uploads to next-gen formats, and optimize JPEG and PNG files in place.

DZIEWA Media Converter — AVIF + WebP vs MegaOptim Image Optimizer – Optimize WebP & AVIF, Compress Images, Convert to WebP & AVIF