PrecisionKit

Add Watermark to PDF

Stamp text onto every page of a PDF — pick the color, opacity and angle. Everything runs in your browser — your file is never uploaded anywhere.

Drop a PDF file here, or click to browse

It stays on your device — nothing is uploaded.

Add a PDF, enter watermark text, and click Add Watermark to see your new file here.

How to watermark a PDF

  1. Add a PDF file.
  2. Enter the watermark text, then choose its color, opacity and angle.
  3. Click "Add Watermark" and download the new file.

Your file stays on your device

This tool reads and rebuilds your PDF entirely in your browser using client-side JavaScript. Your file is never uploaded to a server, so it can't be stored, inspected or lost in transit.

No upload
Your PDF is read and watermarked locally in your browser — nothing is sent to a server.
Applies to every page
The same watermark text, color, opacity and angle are stamped onto each page of the PDF.

Questions

Is the watermark part of the file, or just an overlay in one viewer?

It's written directly into the PDF's page content, so it shows up in every viewer, browser and printer that opens the file — not just a preview overlay.

Can I control how visible the watermark is?

Yes. Adjust the opacity slider to make it as faint or as bold as you need, from a subtle background mark to a solid stamp.

Does it watermark every page?

Yes, the same text, size, color and angle are stamped onto every page of the PDF.

Are my files uploaded anywhere?

No. Watermarking happens entirely in your browser using JavaScript — your PDF is read locally and the watermarked file is assembled on your device. Nothing is sent to a server.