Watermark PDF
Stamp text across every page — CONFIDENTIAL, DRAFT, or anything you like.
Runs on your device · one of 15 free tools
How to watermark a PDF
- 1
Add your PDF
Drop the file in. The preview opens beside the settings so you can judge the mark against your actual content.
- 2
Write the text
Type anything up to 40 characters, or tap a preset — CONFIDENTIAL, DRAFT, COPY, DO NOT SHARE. Your own name or a client's works just as well for tracing a leaked copy.
- 3
Set direction and weight
Diagonal is the convention and covers more of the page; horizontal reads more easily. Pick a colour, then set opacity — the slider stops at 45% deliberately, because a mark you can't read through ruins the document.
- 4
Apply and download
The watermark is drawn into every page's content, so it prints, forwards and survives being converted elsewhere.
What a watermark actually achieves
A watermark is a deterrent and a label, not a lock. Marking a document DRAFT stops someone acting on a version that isn't final. Marking it CONFIDENTIAL removes the excuse that a recipient didn't realise. Putting a specific person's name on each copy you send makes a leak traceable to whoever received that copy — which is often the entire point.
What it doesn't do is prevent copying, and it's honest to say so. Anyone can screenshot a page or retype the contents. If you need to stop a document being opened at all, that's encryption — use the Protect tool to require a password instead.
Choosing an opacity that works
The most common mistake is going too dark. A watermark at 40% competes with your text and makes the document tiring to read, which pushes people to strip it or ignore the document entirely. Somewhere between 12% and 20% is usually right: unmistakable at a glance, invisible once you start reading a paragraph.
Test it the way it will be used. If the document will be printed, remember that most printers render light greys heavier than a screen suggests — err lighter. If it's for screen only, check it against your darkest page rather than the title page.
Frequently asked questions
Can I remove a watermark from a PDF?
Not from a file watermarked this way — the text is drawn into the page content, the same as any other text on it. Keep your unmarked original, which this tool never modifies.
Does the watermark go on every page?
Yes, every page in the document, sized automatically to each page — so mixed portrait and landscape pages each get a mark that fits.
What opacity should I use?
Between 12% and 20% for most documents: clearly visible at a glance but not competing with your text. Err lighter if it will be printed, since printers tend to render light greys heavier than screens do.
Does a watermark stop people copying my document?
No, and no watermark does. It deters casual sharing, labels status like DRAFT, and makes leaks traceable if you put a recipient's name on their copy. To actually prevent opening, use the Protect tool to add a password.
Is my document uploaded?
No. The watermark is drawn in your browser and the new file is built on your device — which matters, since documents worth marking CONFIDENTIAL are exactly the ones you shouldn't be uploading.