LPLocalPDF
100% private · files never uploaded

Watermark PDF

Add a text watermark to every page of a PDF in your browser. Opacity, size, and diagonal options. No upload.

Your file

How to watermark pdf

  1. 1Choose a PDF from your computer.
  2. 2Enter watermark text (e.g. CONFIDENTIAL or your name).
  3. 3Adjust opacity and font size, then apply.
  4. 4Download the watermarked PDF — never uploaded.

FAQ

Can I make a light diagonal watermark?+

Yes. Lower opacity (around 0.15–0.3) and keep diagonal mode for a classic draft stamp.

Is watermarking free?+

Yes for personal use. Processing is local so there is no per-file server cost.

Why use a no-upload PDF tool?

Most free PDF websites ask you to upload contracts, IDs, and invoices to unknown servers. Even if they delete files later, the transfer itself is a privacy risk — and some sites inject watermarks or hard limits.

LocalPDF runs entirely in your browser with open libraries. Your file is never posted to our origin. That also means lower cost for us, so the core tools can stay free while we expand.

Looking for another tool? Try Merge PDF, Split PDF, or Rotate PDF.