Watermark PDF
Draw a diagonal, centred or corner mark on each page. The PDF never leaves the device.
Processed in your browser · nothing uploaded
How it works
- 01
Choose one PDF — or several for merging.
- 02
Enter pages as ranges like 1-3, 5.
- 03
Download the new PDF. The original is untouched on your device.
About this tool
Type the stamp — Confidential, a name, a date. Diagonal is the usual review mark; a corner mark is quieter. Opacity keeps the text readable without hiding the page. Existing page content is copied, not re-rendered.
Questions
- Do you upload my PDF?
- No. Documents are read and rewritten inside your browser with pdf-lib.
- Can I edit password-protected PDFs?
- Not yet. Encrypted files are rejected with a clear message rather than silently failing.
- Will fonts and images stay intact?
- Yes. Pages are copied as objects, not rendered, so text stays selectable and images keep their resolution.