How 108pdf compresses a PDF
First we rebuild the file structure, which often saves space without touching quality. If you need a smaller file, pages are re-rendered as optimised images at the resolution you choose. This is the method that reliably reaches strict limits like 100KB or 200KB for scanned documents.
Heavy compression turns text into an image, so text in the output cannot be selected. For typed documents that must stay searchable, use the Light level.