Spinix Image Optimization

Spinix Image Optimization makes your images smaller and your pages faster, right on your own server. Every image is compressed and served as WebP whenever that makes it smaller, the first images on each page load right away while the rest are lazy-loaded, and the hero image gets priority. Your original files are never changed.

Spinix Image Optimization is developed and maintained by Spinix Technologies Ltd, a UK company.

It fixes these PageSpeed Insights warnings:

• Serve images in next-gen formats. Every JPEG and PNG is converted to WebP (the original is kept in the rare case it is already smaller).

• Efficiently encode images / Increase the compression factor. Smart compression finds the right quality for each image automatically.

• Largest Contentful Paint image was lazily loaded. The first images on a page are never lazy-loaded, and the hero image gets fetchpriority="high".

• LCP request discovery / fetchpriority=high should be applied. When the hero is a CSS background image (for example an Elementor section background), it is preloaded in the page head with high priority, so the browser finds it right away.

• Image elements do not have explicit width and height. Missing dimensions are added to prevent layout shift.

Your originals are safe

All optimized files are written to a separate folder, spinix-webp, inside your uploads folder. Your original uploads are never changed. Switch delivery off, pause, deactivate or delete the plugin, and your site goes straight back to the original images.

Fast

Images are encoded directly with GD or Imagick (whichever your server has). Each image is read once, the right quality is found in memory before anything is written, and the bulk optimizer processes several images in parallel. Progress, time per image and images per minute are shown live on the dashboard.

Features

• Automatic optimization of every new upload

• Background bulk optimization of your existing library, starting the moment you activate the plugin

• Three compression levels: Smart (recommended), Smallest files and Best quality

• PageSpeed-safe compression that stays above a safe quality floor

• WebP delivery with <picture> tags (automatic fallback) or direct URL replacement

• WebP for CSS background images, including page builder CSS files (Elementor and others)

• Smart lazy loading that never delays the first images on the page

• Hero image priority for a better LCP: automatic on every page, works for normal images and background images, with an optional manual choice per page

• Missing width and height added to prevent layout shift (CLS)

• Works with page caching plugins and CDNs (no server rewrite rules required)

• Plays well with WP Rocket, Elementor and other plugins that also lazy-load or prioritize images: you choose which plugin does it, so nothing is done twice

• Images list with status, savings, time taken and the reason for any image that could not be optimized

• Media Library column with savings per image, optimize again or serve the original

• Exclusions by file name, class or folder

• Pause and resume, plus a choice to keep or delete all data when you deactivate

• WP-CLI: wp spinix-images optimize, wp spinix-images status, wp spinix-images reset

External services

This plugin does not connect to any external service. All images are processed on your own server, nothing is sent anywhere and nothing is tracked.

The dashboard has a “Test on PageSpeed” button. dev/) with your site’s home page address, so that you can test your site there. com/privacy.

Source code

All JavaScript and CSS in this plugin is the original, unminified source code. There are no build tools, no compiled files and no third-party libraries.