What it is
The PDF Watermark tool writes text across the pages of a PDF, with control over position, size and transparency.
Why watermark a PDF
Two reasons, and they are quite different.
Marking a copy for a specific purpose. Sending a scanned ID, a proof of address or a bank statement is routine, and it is also how documents get reused later without your knowledge. Writing "for X only, dated" across the page makes that copy obviously unusable for anything else, and it costs nothing.
Marking a state. Draft, confidential, internal, sample. A watermark tells the reader what they are holding before they read a word of it, which prevents the most common document accident: someone acting on a version that was never final.
How to use it
- Add the PDF.
- Type the text and adjust position, size and transparency.
- Download the watermarked file.
What it does and does not do
It is a visual mark, not encryption. Someone with the right software can remove it, and it does not stop copying, printing or forwarding. What it does is remove the excuse of not knowing, and make casual reuse obvious.
The watermark applies to the pages as they are; keep the original if you will need a clean copy.
Nothing is uploaded
The whole operation runs inside your browser. Your file is never sent to a server, never stored and never seen by anyone else. There is no queue, no daily cap and no account: the only real limit is your own device.
Related: the PDF merger and the PDF splitter.