BytCrush documentation
BytCrush optimizes every image in your Media Library in one click, keeps the originals safe, and serves WebP and AVIF automatically.
Large images are the most common reason a WordPress page is slow. BytCrush compresses each image and every size WordPress generates from it, creates WebP (and optionally AVIF) copies, and serves those to browsers that support them. All of it runs on your own server, with the Imagick or GD extension PHP already has. There are no API keys, no quotas, and no images sent anywhere.
Built by Warcal.
Start here
| If you want to… | Read |
|---|---|
| Install it and optimize your library | Getting started |
| Know what every option does | Settings reference |
| Run and follow a bulk optimization, or work on single images | Dashboard and Media Library |
| Understand how WebP and AVIF reach visitors | WebP and AVIF delivery |
| Find, restore or remove your originals | Backups and restoring |
| See what Pro adds and how licensing works | Pro features and licensing |
| Fix something | FAQ and troubleshooting |
| Extend it with code | Developer reference |
| Answer privacy and compliance questions | Privacy and data |
| See what changed | Changelog |
At a glance
- One click, whole library: Optimize all images works through every JPEG, PNG, WebP and GIF in the Media Library, with a live progress ring, savings counters and an activity list. Pause and resume at any time.
- Background runs: the bulk run keeps going on your server after you close the tab. If your host blocks that, an open dashboard tab does the work instead.
- Every size: the main file and every size WordPress or your theme generates are optimized.
- Originals kept: every file is copied byte for byte before it is touched. Restore one image from the Media Library, or all of them from the dashboard.
- Careful compression:
- EXIF rotation is applied before metadata is removed
- the colour profile is kept (with Imagick)
- JPEG quality is never raised above the source's own (with Imagick)
- a file is never replaced by a bigger one
- WebP and AVIF: created next to each file (
photo.jpg.webp) and served with<picture>tags on any host, or with rewrite rules on Apache and LiteSpeed. - Automatic: new uploads are optimized as soon as WordPress has created their sizes.
- Free: everything above, including AVIF.
- Pro: a page speed audit with one-click fixes, the Ultra compression level and Smart target file size.
Requirements
| Minimum | Tested up to | |
|---|---|---|
| WordPress | 5.3 | 7.1 |
| PHP | 7.2 | 8.5 |
The server also needs one of these PHP extensions:
- Imagick (preferred, used when available), or
- GD.
WebP needs an image library built with WebP support. AVIF needs GD on PHP 8.1 or newer with AVIF support, or Imagick with AVIF support. BytCrush → Settings shows what your server can create.