On most WordPress sites, images account for the majority of the page weight. Get them under control and everything loads faster — better for visitors and better for your search ranking. Here’s how to do image optimisation properly.
Resize before you compress
The biggest mistake is uploading full-resolution photos. A modern phone camera produces images several thousand pixels wide, but your site might only display them at 800px. Uploading the giant original wastes enormous bandwidth. Resize images to the largest size they’ll actually be shown at before uploading — this alone can cut file sizes dramatically.
Compress with a plugin
An image-optimisation plugin compresses your images automatically as you upload them, and can bulk-compress your existing library too. Good compression removes data the eye can’t perceive, so files shrink substantially with no visible quality loss. Set it to compress on upload and you’ll never have to think about it again.
Use modern formats like WebP
WebP images are typically much smaller than the equivalent JPEG or PNG at the same quality. Many optimisation plugins generate WebP versions automatically and serve them to browsers that support them, falling back to JPEG for the rest. This is one of the highest-impact image changes you can make.
Enable lazy loading
Lazy loading defers off-screen images until the visitor scrolls to them, so the initial page load only fetches what’s immediately visible. Modern WordPress does this by default, but confirm it’s active — it makes long, image-heavy pages feel much faster.
Serve appropriately sized versions
WordPress generates several sizes of each uploaded image. Make sure your theme uses the right one for each spot rather than loading the full size and scaling it down in the browser. A well-built theme handles this, but it’s worth checking on image-heavy pages.
Consider a CDN for images
A content delivery network stores copies of your images on servers around the world and serves each visitor from the nearest one. For a site with lots of images and a geographically spread audience, this cuts load times noticeably.
Measure the result
Run your site through PageSpeed Insights before and after. Image optimisation usually produces one of the biggest single improvements in the score. Combined with caching, it’s the foundation of a fast WordPress site.
Need a hand setting up compression and WebP across an existing library? We can configure it for you — just ask.
