Add Watermark

Stamp a text watermark on every page of your PDF.

Processed in your browser — files never uploaded

Drop your PDF file here

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Max file size: 100MB

Add Watermark online, free and secure

Stamp a text watermark across every page of a PDF to mark documents as Confidential, Draft, or with your brand. Adjust size, opacity, angle, and color — processed entirely in your browser.

How to add watermark

  1. Upload your PDF

    Select the PDF you want to watermark.

  2. Customize the watermark

    Type your text and set the font size, opacity, angle, and color.

  3. Download the watermarked PDF

    Save your document with the watermark applied to all pages.

Why use Kobra PDF to add watermark

  • Mark documents as Draft, Confidential, or branded
  • Control opacity, angle, size, and color
  • Processed in your browser for privacy

Add Watermark — frequently asked questions

Can I control how visible the watermark is?
Yes. Adjust the opacity so the watermark can be a subtle background mark or a bold, prominent stamp.
Is the watermark applied to every page?
Yes. Your watermark text is stamped consistently across all pages of the document.
Can I add an image watermark, like a logo?
This tool applies text watermarks. For a logo, add it as content using the Edit PDF tool.
Is my document uploaded anywhere?
No. Watermarking runs in your browser, so your file is never sent to a server.

Kobra PDF — Free online PDF toolkit