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Watermark

Add a watermark

Stamp DRAFT, CONFIDENTIAL, or custom text across every page. Adjust opacity and position locally.

Runs in your browser. Your PDF stays on this device — nothing is uploaded for processing.

Custom text

Any short label you need.

Opacity control

Keep it subtle or unmistakable.

Placement

Center, corners, or tiled diagonal.

Private

Watermarking never uploads the file.

Use the tool

How it works

A stamp that stays offline

pdf-lib draws your watermark onto each page of a copied document before download.

Three steps

  1. 1

    Load a PDF

    Choose the file to stamp.

  2. 2

    Configure

    Set text, opacity, and placement.

  3. 3

    Download

    Save the watermarked PDF.