Free PDF Tool

Add Watermark to PDF

Stamp custom diagonal text on every page of a PDF. Add CONFIDENTIAL, DRAFT, or any custom text watermark to your document.

Secure HTTPS Processes in seconds Auto-deleted in 15 min Always free

Drop your file here

Tap to upload

or click to browse your files

PDF only · Max 50 MB

How to Add Watermark to PDF

1
Upload your file

Drag & drop or click the area above to select your PDF file.

2
Set watermark text & click

Your file are securely uploaded and processed on our server in seconds.

3
Download instantly

Save your result file. It's automatically deleted from our servers within 15 minutes.

Custom Text

Set any watermark text: CONFIDENTIAL, DRAFT, your company name, or any custom label.

3 Opacity Levels

Choose Light, Medium, or Dark opacity to control how prominently the watermark appears.

All Pages at Once

Watermark is applied to every page of the PDF in a single pass.

What Is a PDF Watermark?

A watermark is a text stamp printed diagonally across every page of a PDF, typically semi-transparent, used to indicate the status or ownership of a document. Common watermarks include "CONFIDENTIAL", "DRAFT", "DO NOT COPY", a company name, or a person's name to identify who received a document.

When to Use PDF Watermarking

  • Mark confidential documents — Stamping "CONFIDENTIAL" on every page signals handling requirements to recipients.
  • Draft review copies — Marking documents as "DRAFT" prevents unfinished versions being mistaken for final outputs.
  • Attribution — Adding a company name or URL to shared PDFs establishes provenance and discourages unauthorised redistribution.
  • Client copies — Watermarking with a client's name personalises a document and deters sharing outside the intended audience.
  • Legal protection — Watermarking intellectual property or proprietary reports adds a visible deterrent to unauthorised use.

How the Watermark Is Applied

The watermark text is rendered on each page at 45° using PyMuPDF's text insertion engine. The font size scales proportionally with the page dimensions, and the opacity is controlled by a greyscale colour value. The watermark is added as a page content layer — it is visible but does not affect the underlying text, which remains searchable and selectable.

Frequently Asked Questions

Can the watermark be removed later?

The watermark is added as a content layer on each page. Removing it requires a full PDF editor with content editing capabilities. For casual protection, this is sufficient — but it should not be considered tamper-proof against someone with a professional PDF editor.

Does the watermark affect the original text?

No. The original text and content are unchanged. The watermark is a visual overlay. The underlying text remains searchable and selectable.

Can I choose the watermark colour?

Currently the watermark is rendered in greyscale. The opacity slider controls how dark or light it appears: Light, Medium, or Dark.

Is there a character limit for watermark text?

There is no strict limit, but shorter text (1-3 words) renders more cleanly. Very long text may wrap or appear crowded on smaller pages.

Are the files deleted after processing?

Yes — both the original and watermarked PDF are deleted within 15 minutes.