1. Use the right format for the content
- Photographs: JPG, WebP or AVIF. Avoid PNG for photos.
- Graphics with flat colour, text or transparency: PNG or WebP.
- Maximum compression for the web: AVIF, with WebP or JPG as fallback.
2. Resize to the size it will be shown at
A 6000 pixel wide photo displayed in a 800 pixel column wastes most of its pixels. Resizing to roughly the largest size it will appear at, doubled for high-density screens, often saves far more than any quality tweak. Use the resize option with the aspect ratio lock on.
3. Lower the quality a little, not a lot
For lossy formats, the first steps down from maximum quality save a lot of space with little visible change. Try 80 to 85 for WebP and JPG and compare. Check sizes in the result list, and look at the picture at full size before keeping it.
4. Drop what you do not need
Metadata and embedded previews add size and can reveal location. Converting here writes a clean file without them. Avoid repeatedly re-saving lossy files, since each save loses detail.