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Security & Privacy

How to Add a Watermark to a PDF

Stamp DRAFT, CONFIDENTIAL or a recipient name across every page — how to make it readable without obscuring the document underneath.

May 24, 20262 min read

A watermark states what a document is before anyone reads a word of it: a draft, a copy, confidential, issued to a named person. It is a labelling device, not a security control, and it is very good at the job it actually does.

Add a watermark

  1. 1Open the Add Watermark tool and add your PDF.
  2. 2Type the text — DRAFT, CONFIDENTIAL, a name, a date.
  3. 3Set the angle, size and opacity. Diagonal at low opacity is the convention for a reason.
  4. 4Preview it over a text-heavy page, not the title page.
  5. 5Apply and download.

Getting the settings right

SettingRecommendedWhy
Opacity10–20%Legible as a label, transparent enough to read through
Angle45 degreesCrosses the text without following any line of it
SizeRoughly half the page widthUnmistakable without swamping the content
ColourMid greyNeutral in print and on screen
PositionCentredCannot be cropped off the edge

What a watermark does and does not do

It communicates status, discourages casual misuse, and — when it carries a recipient name — makes a leaked copy traceable back to who was given it. That last use is the one with real teeth, because people behave differently with a document that has their own name across it.

It does not prevent copying, printing, editing or redistribution. Anyone determined can remove it, particularly from a digital PDF where it is simply another object on the page. Treat it as a label, not a lock.

Watermarking each recipient differently

For circulating a sensitive draft, generate one copy per recipient with their name and the date on it. It costs a few minutes, it changes how the document is handled, and if it does leak you know which copy it was.

Removing one

On a document you own — a draft becoming final, a template you are reusing — go back to the source and export again without it. Removing a watermark from someone else's document to obscure its provenance is a different matter, and usually a licensing or copyright breach.

Do it now

Add Watermark

Add text or image watermarks. It runs in this browser tab — your file is not uploaded anywhere.

Open Add Watermark

Frequently asked questions

Does a watermark stop people copying my PDF?+

No. It labels the document; it does not restrict any action.

What opacity should I use?+

10–20%. Above 30% the document becomes hard to read; below 10% the watermark stops registering.

Can I watermark only some pages?+

Yes, though for a status label it is usually clearer on every page.

Can a watermark be removed?+

From a digital PDF, by someone determined — it is an object on the page like any other.

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