How to watermark a PDF

Mark a PDF as a draft, confidential, or yours, on every page or just a few.

Steps

Add your PDF
Drag your PDF onto the box, or click Choose a file. It opens right in your browser. Nothing is uploaded.
Type the watermark text
In Watermark text, type what should appear, like CONFIDENTIAL, DRAFT, or your name.
Style it
Pick Gray, Red, or Blue, turn Diagonal on or off, and set the Size and Opacity sliders.
Choose the pages
Leave Pages empty for every page, or type pages like 1-3, 8.
Click Add watermark
Then click Download to save the watermarked PDF.

An opacity around 20 to 30 percent keeps the page readable.
The watermark font covers Latin letters. Other scripts and emoji are left out, and you'll be warned.

Can someone remove the watermark?: It's drawn into each page, so it can't simply be switched off. A determined person with editing software could cover it, so don't rely on it alone for security.
Can I use a logo as a watermark?: Use Edit PDF to place an image on the page. Text watermarks are made here.

Ready? Watermark PDF is free.

Stamp text across pages. Works in your browser, no sign up.