Watermark PDF
Drop PDFs, or browse
The watermark is stamped across every page
Choose one or more PDFs.
Type the watermark text and pick an opacity: Light, Medium, or Strong.
Press "Watermark & download" — several files arrive together as a ZIP.
Stamping DRAFT, CONFIDENTIAL, or your company name across a document is the classic way to control how it gets shared. This tool draws a diagonal text watermark across every page of your PDF, with the text and opacity you choose — processed entirely on your own device.
100% private“Watermarking happens inside your browser with the pdf-lib engine. The documents never leave your machine — which matters, since watermarked files are usually the sensitive ones.”
The text is drawn semi-transparent above the page content, so everything underneath stays readable — like an ink stamp on paper.
It becomes a permanent part of the page content. There is no flag a viewer can toggle off, though determined editing tools can always alter any PDF.