Watermark PDF
Add a diagonal or horizontal text watermark with your choice of colour, size and transparency. Runs entirely in your browser.
Free · no sign-in · files stay on your device
FAQ
Can I control how strong it looks?
Yes — the opacity slider goes from a faint 10% up to fully solid.
Is my file uploaded?
No — this tool runs entirely in your browser. The file never leaves your device.
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