PDF Watermark Adder
Add a diagonal text watermark to every page of a PDF — control text and opacity, no upload.
How to use this tool
- 1Click the upload zone and select a PDF file.
- 2Enter your watermark text (e.g. DRAFT, CONFIDENTIAL, or your name).
- 3Adjust the opacity slider.
- 4Click 'Apply Watermark & Download' to save the watermarked PDF.
About PDF Watermark Adder
Adding a watermark to a PDF before distributing it is standard practice for draft documents, confidential reports, and licensed content. This tool uses pdf-lib to draw a diagonal text watermark centered on every page of your PDF. You control the watermark text and opacity. The text is drawn at a 45-degree angle in a large font, centered on each page. The opacity slider lets you choose between a subtle background watermark and a prominent foreground stamp. The watermark is embedded as a PDF text object — it is permanent once downloaded. Runs entirely in your browser using pdf-lib.
Frequently asked questions
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