Images are usually the heaviest part of a page. Oversized ones slow pages down, especially on phones, and audit tools report them.
Why Joomla sites get it
Joomla stores images at the size they were uploaded. A photo straight from a phone or camera is typically several megabytes and thousands of pixels wide, while the article displays it a few hundred pixels wide. Screenshots saved as PNG can be large too.
Fix it by hand
- Resize the image to about the largest width it is shown at (1200 pixels is plenty for most article images).
- Save photos as JPEG or WebP at around 80% quality; keep PNG for screenshots and graphics with flat colours.
- Upload it with the same file name so the articles that use it don’t need editing, and clear any page cache. Some hosting control panels have an image tool that resizes files in place.
Fix it with MetaGen
MetaGen’s site scan records the size of every image your articles use. The Large images row lists those of 500 KB or more, with the articles that use them, so you can start with the ones that make the biggest difference.
MetaGen is free for Joomla 5 and 6. See all the SEO warnings MetaGen checks.
