Stamping
Add a watermark to a PDF
A diagonal word across the page is the usual way of saying this document is a draft, a copy, or not to be circulated. Set the text, the angle and how strongly it shows.
Result
A watermark is a label, not a lock
It is worth being clear about what this does. The text is drawn on top of the page as ordinary page content, which means it is visible when printed and when read, and it travels with the file. It is not a security measure. Anyone determined enough can remove it, and no watermark on any system prevents a screenshot.
Use it for what it is good at: signalling status. DRAFT so nobody quotes a version that is still moving. CONFIDENTIAL so a printout left on a desk explains itself. SAMPLE on a document you are showing rather than issuing. Keep the opacity low enough that the text underneath stays comfortably readable; around 18% is usually the sweet spot.
Common questions
Can I use an image or a logo instead of text?
Not on this page. If you need a logo watermark, place it in your source document before exporting to PDF, where you also get much better control over its position.
Can I remove a watermark from a PDF?
Not with this tool, and generally not cleanly. Once the text is drawn into the page content stream it is mixed in with everything else. Go back to the unwatermarked source instead.
Will it appear behind the text or in front?
In front, but at low opacity, so the page reads through it. Drawing behind existing content is not reliably possible without rebuilding the page.
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