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Add a Watermark to a PDF — Free, No Upload

How it works — 100% in your browser, no upload
Quick answer: add a PDF, type your stamp text, set the opacity and angle, then download. Every page gets the mark, and the whole operation runs inside your browser.

Drop a PDF here to watermark

Stamped locally with pdf-lib — the document is never uploaded.

How to watermark a PDF

  1. Add a PDF. Drop the document onto the drop zone.
  2. Type the text. Common choices are DRAFT, CONFIDENTIAL or a client name.
  3. Style the stamp. Adjust size, colour, opacity and whether it runs diagonally.
  4. Download. Save the watermarked PDF.

Frequently asked questions

How do I watermark a copy of my ID or passport?

Press the 'ID copy' preset, then replace [purpose] with who it is for, e.g. 'Copy for rental application only - 30 Sep 2026'. A copy stamped with its purpose and date is much harder to reuse for anything else. Everything runs in your browser, so the ID is never uploaded.

What opacity should a PDF watermark use?

Around 15-25% keeps the mark clearly visible while leaving the text underneath easy to read, both on screen and in print.

Is the watermark on every page?

Yes — the text is drawn once per page, so multi-page contracts and reports are covered end to end.

Can the watermark be deleted afterwards?

It becomes part of the page content stream, so it is not a removable layer. Keep an unstamped original for your own records.

Related tools

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