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Add a Watermark

Stamp text like DRAFT or CONFIDENTIAL across every page, diagonal or straight, at the opacity you choose. Nothing leaves this tab.

We never watermark your files; this tool is for when you want to stamp your own documents.

Drag your PDF file here

or choose from your computer

How it works

  • The watermark is drawn into each page with pdf-lib (bold Helvetica, gray, at your chosen size, color, and opacity), centered straight or at 45°. The live preview shows the first page exactly as it will download.
  • Character support: the built-in PDF fonts cover Latin (Western European) characters. Unsupported characters are skipped with a warning rather than failing mid-file.
  • This is a visual stamp, not security. A determined user can remove a watermark; it deters casual misuse and marks status, nothing more.