JPG is widely supported and useful for photographs. It uses lossy compression and cannot retain transparent backgrounds; choose the background colour you want before exporting.

PNG supports transparency and lossless pixel compression. It can be a good fit for diagrams and screenshots, but photographic files can be large. Its export does not use the lossy quality slider.

WebP supports transparency and can produce compact images, depending on the image and quality setting. Browser encoder support varies. Always check the result before replacing an original.

If your goal is only to remove embedded metadata, preserve original quality avoids recompression. A cleaned file is not guaranteed to be smaller after conversion, and the report shows the actual size change.