💧 PDF Tools

Add Watermark to PDF

Add a text watermark to every page of a PDF. Choose diagonal placement and opacity — great for CONFIDENTIAL or DRAFT stamps. Loading and watermarking both happen entirely in your browser, so you can handle confidential documents without ever uploading them.

Drag & drop a PDF, or click to choose

Load one PDF. It is processed on your device only and never leaves it.

How to add a watermark

Load one PDF, type the watermark text, choose opacity and angle, and press the button. Everything is processed on your device, so your file is never sent anywhere.

  • Load a PDF: drop it on the box or click to choose.
  • Set the text and look: watermark text (e.g. CONFIDENTIAL), opacity, and whether to place it diagonally.
  • Add & download: a PDF with the watermark centered on every page is saved (named originalname_watermark.pdf).

Handy for

  • Marking documents as CONFIDENTIAL, DRAFT or COPY before sharing
  • Making it obvious at a glance that a file is a draft or sample
  • Stamping a watermark locally without uploading to an online service

The watermark is drawn in semi-transparent gray, centered on every page. The standard font can't render non-Latin scripts (use Latin letters/digits). It's embedded into the page content and is not a tamper-proof guarantee. Password-protected or corrupted PDFs may fail to load.

FAQ

Are my PDFs sent to a server?
No. Loading and watermarking both happen entirely in your browser (on your device), and your PDFs are never transmitted to or stored on any server. Once the page has loaded it even works offline.
Can I change the angle and opacity?
Yes. You can turn diagonal (45°) placement on or off and pick the opacity (light, normal, strong). The font size scales to the page and the watermark is centered on every page.
Can the watermark be removed later?
The watermark is drawn into the page content, so it isn't easily removed. It could still be stripped in an editor and is not a tamper-proof guarantee. Your original file is left unchanged, so keep it if you need it.