Watermark a PDF with DRAFT, CONFIDENTIAL or a name

How it works

1. Type the word. One line. DRAFT, CONFIDENTIAL, NOT FOR DISTRIBUTION, a client’s name, or the name of the person this copy is going to — the last of those is what makes a leaked copy traceable.
2. Set how solid and how big. A quarter opacity at 48 points is a comfortable single word across an A4 page. Turn it up and you start to lose the text underneath; turn the size down and tile it if you want the page covered.
3. Read a page through it. Open the result and actually read a paragraph the watermark crosses. If you cannot, your reader will not either, and the opacity needs to come down.

What the options do

The form above lists the options this tool is running today, straight from the server. This is what they are for.

Watermark text

The only required field, and one line of it. Short words work best: the text is drawn at a fixed size and nothing is scaled to fit, so a long phrase at a large size runs off both edges of the page. Accented characters and non-English text are fine — Helvetica Bold is tried first and a fuller font is substituted when it cannot draw a character, and anything neither can draw is refused rather than stamped wrongly. Putting the recipient’s name or email address here is the one genuinely useful security use of a watermark: it does not stop a copy being shared, but it tells you whose copy it was.

Text size (pt)

Six to 400 points, 48 by default. Forty-eight is about right for a single word across the middle of an A4 page. When you are tiling, come down to 18 or 24: the tiles step by the width of the text, so a large font gives you a handful of enormous words rather than a wash. Nothing is measured against the page for you, so a word that is wider than the sheet simply hangs off both sides.

How solid it is

A genuine alpha, not a pale grey, which means the ink underneath shows through rather than being covered. 0.25 is a light wash you can read a paragraph through comfortably. Around 0.5 the watermark starts competing with the body text. At 1 it is opaque and will hide whatever it crosses, which occasionally is the point — an opaque DRAFT across a signature block — but is rarely what anyone wants. The lowest value accepted is 0.05, which is close to invisible on screen and often invisible on a photocopy.

Angle (degrees)

Forty-five by default: the diagonal that runs from the bottom left to the top right, and the angle every reader recognises as a watermark rather than as content. Zero lies flat across the page, which reads more like a banner. Negative angles run the other way, from top left down to bottom right. When the layout is tiled, the whole grid is turned with the text, so the pattern stays even and square to itself at any angle.

Colour

Mid grey by default, because grey reads as a mark on the page rather than as part of the document. Red at a low opacity survives on a scan or a photocopy where grey turns to nothing, which is worth knowing if the document will be printed and re-scanned. Avoid anything close to the colour of your own text at a high opacity, and avoid black entirely — a black watermark at any useful opacity is just a grey one that fights harder with the body text.

Layout

Once across the middle, or repeated over the whole page. Once is the polite version, and the right choice for a draft going to a colleague. Tiling covers everything, which makes it harder to crop out, harder to hide behind a white box, and considerably harder to read the document through — so drop the opacity and the size together when you choose it. Tiles are stepped by the text width plus a little, with a floor, so a tiny font cannot ask for tens of thousands of copies.

Pages to watermark

Which pages get marked. ‘2-’ leaves a cover clean, which is common for a report where the title page carries the status in words already. You can name 1-5, 3,7,9 or ‘odd’. Everything else is left untouched, and the result says how many pages were marked — worth a glance, because a mistyped range that marks nothing you meant is easy to miss on a long document.

What this tool does not do

• A watermark is a label, not protection. It is drawn on top of the page and any PDF editor will remove it in about a minute, because it is ordinary page content like everything else there. Treat it as a deterrent and as a way of saying which copy this is — never as a control on what somebody can do with the file.
• It does not stop copying, printing, editing or forwarding. Protect can add a password and set permissions, and even those depend on the reader choosing to honour them.
• It is drawn over the content, so at a high opacity it hides what it crosses. That is exactly why the transparency control exists, and why it defaults low.
• One line of text, one colour, one position per run. No images, no logos, no line breaks, and no per-page text — a different word on each page means running the tool once per page range.
• Nothing is scaled to fit the page. A long phrase at a large size runs off both edges; shorten the words or drop the point size.
• It cannot be undone. The text becomes part of the page, so keep the unwatermarked original — you will want it the moment the draft becomes final.

What happens to your file

The file is uploaded because Watermark PDF runs on our server rather than in the browser tab. It is kept for at most 2 hours and the result you download for 24 hours, then a scheduled job deletes both — a job has to be able to read the file while it runs, and you have to be able to retry a failed conversion without re-uploading. Neither needs longer.

Nothing about the contents is logged, and no one reads your documents. The retention page lists the same numbers the code enforces, and the privacy policy says who can reach the storage they sit in.

Questions

Can someone remove the watermark?

Yes, and you should plan on that. It is drawn into the page as ordinary content, so any editor that can delete an object can delete it, and a determined person can rebuild the page without it. What a watermark actually buys you is that nobody can forward the file without noticing what it says, and that a leaked copy carrying a name points somewhere.

How do I stop people copying or printing my PDF?

You cannot, not really, and anyone claiming otherwise is selling something. A password on the file stops someone opening it without the password; permissions ask readers not to allow printing and most honour that, but nothing forces them to. Anyone who can read a document on screen can photograph it.

My watermark is hiding the text underneath.

Bring the opacity down — 0.25 is a comfortable starting point, and anything above 0.5 competes with body text. A lighter colour helps too, and if you are tiling, reducing the point size spreads the marks out and leaves more of the page clear.

Can I use my logo as the watermark?

No, this places text only. The nearest thing available is your organisation’s name typed out, which has the advantage of being legible when the file is photocopied — a pale logo very often is not.

Should I tile it or put it across the middle once?

Once for a draft circulating internally, where the point is to remind people of its status. Tiled for a document going outside, where the point is to make screenshots and partial copies obviously marked. Tiling costs readability, so lower the opacity when you turn it on.

Can I leave the cover page unmarked?

Yes — set the pages to 2-, and the first sheet is left alone. Any range works: name individual pages, use ‘odd’ or ‘even’, or write 5- to start partway through.