WordPress images, automatically smaller
WebberZone Image Optimizer converts the images already in your media library to WebP and AVIF, and serves each visitor the smallest file their browser can read. Typically 40–60% smaller, with no visible difference.
Three steps, all on your own server
There's no dashboard to sign into and no image to upload anywhere else. The plugin runs inside WordPress using the image libraries your host already gave you.
Test what your server can actually do
At activation, the plugin encodes a small bundled image with GD and Imagick rather than trusting what the extension claims to support. It caches which formats really work, so AVIF is only offered when it will succeed.
Convert without touching the original
New uploads convert automatically; existing libraries convert through a resumable, database-backed queue. Each result is written next to the source as a sidecar file — photo.jpg gains photo.jpg.webp — and a copy that isn't actually smaller is discarded.
Let the browser choose, safely
Every image is wrapped in a <picture> element listing the available formats. The browser picks the one it supports, so the HTML is identical for every visitor and every cache layer — page cache, CDN, proxy — can cache it without any special configuration.
Not a cloud service, and not an Accept-header hack
Most image optimization plugins either ship your media to a third-party API, or rewrite delivery based on the browser's Accept header. Both come with trade-offs this plugin avoids.
| Image Optimizer | Cloud optimization services | Accept-header rewriting | |
|---|---|---|---|
| Where images go | Never leave your server | Uploaded to a third-party API | Never leave your server |
| Account / API key | None required | Required, usually metered | Varies |
| Ongoing cost | Free, no quota | Monthly quota or subscription | Free |
| Behind a CDN or page cache | Safe — same HTML for everyone | Depends on provider | Risky unless every cache layer honors Vary: Accept |
| If the service disappears | Nothing to lose — it's not a service | Optimized images can stop being served | N/A |
Runs entirely on your server
Your images are never uploaded anywhere. The plugin makes no outbound network requests of any kind — no external service, no API key, no monthly image quota, no account to create, and nothing that can stop working because a company shut down or changed its pricing.
WebP & AVIF
Generated together or separately, with AVIF used wherever your server supports it.
Originals never touched
Each optimized copy is written alongside the original as a sidecar file. Nothing overwrites, replaces, or re-saves the source.
Delivery survives caching
Images are wrapped in a <picture> element, so the browser picks the format — not a cache-breaking Accept-header rewrite.
Resumable bulk conversion
A database-backed queue works through your library in batches. Close the tab and nothing is lost.
Multisite aware
Per-site queues and settings, with tables created automatically for new sites on a network.
WP-CLI included
wp wzio status, convert, queue, run, and clean for scripting and deployments.