TheDock Media – Image Optimizer: Compress Images, Convert to WebP & AVIF

TheDock Media is an image optimizer for WordPress: it compresses images, resizes oversized photos and converts them to WebP and AVIF, so pages load faster and score better on Core Web Vitals.

It runs on your own server, for free, with no account, no monthly quota and no credits. Optimize every new upload and your whole existing library in bulk. The plugin also checks what your server can do, so you know which formats you get before you start.

Want to see the difference first? Try it on one of your files at media.thedock.io.

Free, on your server

• Modern formats: new uploads are saved as AVIF or WebP (when your server supports them), JPEG otherwise.
• Compression levels: Best, Balanced, Smallest, or your own number, tuned per format.
• Largest size: oversized photos are scaled down to what your site actually shows.
• Your whole library: the Library screen finds heavy, oversized and badly compressed images and optimizes them in the background, one at a time.
• Dashboard widget: what can still be optimized and how much it saves, with a one-click Optimize button.
• TIFF to web: print TIFFs become images browsers can show (when your server’s image library reads TIFF).
• Replace originals (optional): free disk space by keeping only the optimized file, and only when it is smaller.
• Safe on small servers: photos too big for your server’s memory are stored as uploaded instead of crashing the upload, and ImageMagick gets a memory budget inside containers.

Everything is done by WordPress’s own image code with your chosen settings, so file names, sizes and metadata are exactly what WordPress makes. Themes, page builders, backups and migrations keep working.

Know what your server can do

The Server screen (also in Tools → Site Health) checks this server and explains the results in plain words:

• which image library WordPress uses (ImageMagick or GD) and which formats it can read and write;
• how large a photo it can process comfortably with its memory;
• whether background tasks (WP-Cron) run, the time limit per request, the upload limit and free disk space;
• a speed test that times WebP and AVIF on this server and estimates seconds per photo;
• a feature-by-feature comparison of this server with TheDock Cloud, and a report to paste into support requests.

TheDock Cloud (optional)

Click Connect to TheDock to link your site to a TheDock account (you can create one on the way), and processing moves to TheDock’s servers (Stockholm, EU). Your TheDock account can try it free on 5 files, once, across all your sites; after that it is $2 per site per month, or $20 per site per year:

• no image work on your server: uploads return instantly, whatever their size;
• AVIF and WebP on every site, encoded fast, for photos up to 100 MP;
• videos: a web MP4 that plays everywhere, a smaller AV1 or VP9 version and a poster image;
• Compare before choosing: up to 8 formats and quality levels on your own image or video, side by side and zoomable, each with a score for how close it looks to the original;
• bulk optimization in parallel.

The plugin works fully without TheDock Cloud. Nothing is sent anywhere unless you connect it.

External services

This plugin connects to TheDock Media API (https://media-api.thedock.space) only when you connect your site to TheDock (TheDock Cloud). Without a key, it makes no outside requests, except when an administrator clicks “Test connection to TheDock” on the Server screen, which sends one request without your key or any file, to check that the service can be reached (like any web request, it carries your site’s address).

With a key, the plugin sends:

• for each image or video it processes (new uploads, and existing files you choose to optimize or compare): the file itself, its file name, type and size, its attachment ID in your media library, and the sizes and settings to create;
• your API key and your site’s address with every request, to identify your account;
• the address of your site’s notification endpoint, so the service can tell the site when a file is ready.

Files are processed in the EU (Stockholm) and deleted from the service as soon as your site confirms it has downloaded the results, and in any case within 24 hours. No other site data is sent.

Connecting uses TheDock’s dashboard (https://thedock.app): when an administrator clicks “Connect to TheDock”, the browser goes to thedock.app with your site’s address and the wp-admin address to return to. After signing in there, thedock.app sends the browser back with a one-time code, and the plugin sends that code and your site’s address to https://thedock.app/api/media/connect/exchange to receive your site’s key. Links to thedock.app from the plugin carry tags (utm_source=wordpress) so TheDock can see they came from the plugin. Terms of service https://thedock.app/terms, privacy policy https://thedock.app/privacy.

The service is provided by TheDock (DAC Sweden AB): terms of service https://media.thedock.io/terms, privacy policy https://media.thedock.io/privacy.

Third-party resources

• Geist and Geist Mono fonts, used in the plugin’s admin screens: Copyright 2024 The Geist Project Authors (https://github.com/vercel/geist-font), licensed under the SIL Open Font License 1.1 (assets/fonts/OFL.txt). The fonts are bundled with the plugin and never loaded from anywhere else.