Watermark PDF

Stamp a diagonal text watermark across every page of a PDF, free and in your browser. Set the text and opacity. No upload, no sign-up.

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Drop a PDF here, or click to choose
Watermarked on your device · nothing is uploaded
your file never leaves your browser

How to watermark a PDF

Drop your PDF onto the box above (or click to choose it). Type your watermark text, drag the opacity slider until it looks right, then click Add watermark. A watermarked PDF is ready to download — every page stamped, all in your browser.

Why watermark a PDF?

A watermark marks a document as confidential, a draft, or a sample, and discourages unauthorised reuse. Applying it locally keeps the original private and lets you brand or protect a file in seconds without any desktop software.

Questions

Does this upload my PDF?
No. The watermark is drawn in your browser with pdf-lib, so the file never leaves your device. It's instant and private — important for marking sensitive or draft documents.
Can I control how it looks?
Yes. Type any text — “CONFIDENTIAL”, “DRAFT”, a name, a date — and set the opacity so it's visible but doesn't obscure the page. It's drawn once per page on a 45° diagonal, centred and scaled to fit the page size.