300 KB is a sensible default: most portals accept it, and at this size a scan still looks like a scan rather than a photocopy of a photocopy.
No upload. No watermark. No sign-up. Every tool mentioned here runs inside your browser.
Roughly 1200–1500 pixels of width per page for a typical single-page scan — enough to read a signature, a stamp and a photograph clearly.
For a two-page document you get about half that per page, which is still fine for text-heavy forms.
If the preview text becomes hard to read at 100% zoom, stop. A rejected application costs more than a slightly larger file.
If the portal has no stated limit, do not compress at all — or use Safe mode, which only removes internal redundancy.
No. Compression changes image quality, never the number of pages.

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