Images are usually the largest part of a page and the easiest win.
- Resize before uploading. A 4000px photo displayed at 800px wastes bandwidth - resize to roughly twice the display size.
- Use WebP or AVIF. Both are far smaller than JPEG or PNG at the same quality, and all current browsers support them.
- Compress. Aim for under about 200 KB per image; tools such as Squoosh, TinyPNG or the LiteSpeed image optimiser do it in bulk.
- Lazy-load. Load images below the fold only as the visitor scrolls - a cache plugin does this automatically.
- Use SVG for logos and icons - sharp at any size and only a few kilobytes.
