Watermark PDF
Updated Files never leave your device
Mark documents as DRAFT, CONFIDENTIAL or with your company name. The watermark is placed diagonally across every page.
Choose a PDF
or drop files here · 🔒 processed on your device, never uploaded
How to watermark pdf
- Choose a PDF.
- Type the watermark and set the opacity.
- Process and download.
Private by design
PDF Fox runs entirely in your browser using open-source PDF libraries. Your documents are never uploaded, stored or seen by anyone — close the tab and they're gone.
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Frequently asked questions
Are my files uploaded?
No. PDF Fox processes files with JavaScript inside your browser. Nothing is sent to a server, so your documents stay private.
Is it really free?
Yes — no sign-up, no watermark, no page limit. Very large files are limited only by your device's memory.
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