PDF Tools
Watermark PDF
Stamp a diagonal text watermark — CONFIDENTIAL, DRAFT, your name — across every page.
Working…
100% private — your file is processed in your browser and never uploaded.
About this tool
Mark documents before sharing: a diagonal, semi-transparent watermark like CONFIDENTIAL, DRAFT or your company name is stamped across every page, auto-sized to fit.
Watermarking runs locally — the very documents you'd watermark are the ones you shouldn't upload anywhere.
How to use
- Choose a PDF.
- Type the watermark text.
- Click Add watermark — the stamped PDF downloads.
Frequently asked questions
It becomes part of the page content, so casual removal is hard — but no watermark is tamper-proof against determined editing.
This version uses a centered diagonal gray stamp at 30% opacity — the standard document-marking convention.
The 30% opacity keeps the underlying content fully readable.