Watermark PDF — Free, In Browser

Add a diagonal text watermark to every page. 100% in your browser — free, no sign-up, no upload.

How to

  1. 1Choose your PDF — it stays in your browser and is never uploaded.
  2. 2Type the watermark text and set its opacity and size.
  3. 3Click apply to stamp it diagonally across every page.
  4. 4Download the watermarked PDF.

What is a PDF watermark?

A watermark is text stamped across every page — words like CONFIDENTIAL, DRAFT, or a company name — usually set on a diagonal at low opacity so it is visible without hiding the content beneath. It marks a document's status or ownership at a glance.

How watermarking works here

You type the text and set its opacity and size; we draw it diagonally across every page with pdf-lib, on top of the existing content, entirely in your browser. The watermark is written into the PDF so it shows in every viewer and on print, not just on screen.

When to watermark a PDF

Mark drafts so an old version is not mistaken for final, label sensitive files CONFIDENTIAL before sharing, or stamp ownership on documents you send out. A faint watermark also discourages casual copying or reuse without blocking readability.

Watermark PDF vs paid tools

Many online watermarkers limit free use or add their own branding to the page, and Acrobat is a paid product. This tool watermarks every page of a PDF free, with no upload and no added branding — your document stays on your device.

FAQ

Does the watermark appear on every page?+

Yes. The text is stamped diagonally across all pages so the whole document is marked consistently.

Can I control how visible the watermark is?+

Yes. Adjust the opacity and size so it is clearly visible without making the underlying content hard to read.

Is my PDF uploaded when watermarking?+

No. The watermark is applied entirely in your browser, so your document stays on your device.

Does the tool add its own branding?+

No. Only your watermark text is added — there is no extra logo or branding, unlike some free watermarkers.

Is it free?+

Yes, completely free — no sign-up and no watermark.

Is my data private?+

Yes — this tool runs entirely in your browser. Your files and text are never uploaded.

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