Add a Watermark to a PDF
Add the PDF tools to your home screen and they work with no connection — your files never leave your device either way.
- Tap the Share button in Safari
- Scroll down and tap Add to Home Screen
Stamp text such as DRAFT, CONFIDENTIAL or a company name diagonally across every page of a PDF, with control over opacity, angle and size. Runs entirely in your browser.
How it works
The tool embeds the standard Helvetica Bold font, then draws your text across the middle of each page at the angle and transparency you choose. Opacity is a real PDF property, so the underlying content stays fully readable through the mark rather than being covered up.
Placement accounts for the rotation: the text is measured, then its centre point is offset along the angle so the watermark sits centred on the page rather than drifting towards a corner as the angle changes.
The watermark becomes part of the page content, so it prints and appears in every PDF reader — but for the same reason it can also be edited out by anyone with the right software.
Worked example
You're circulating a proposal for comment and don't want an early version mistaken for the final one. Watermarking it with "DRAFT" at 45° and 0.15 opacity makes the status obvious on every page and in every printout, without making the document harder to read.
For a document going to an external party, something like "CONFIDENTIAL — NOT FOR DISTRIBUTION" at a smaller font size sets expectations clearly on each page.
Common questions
What opacity should I use?
Around 0.15 is the usual choice — clearly visible but still easy to read the text underneath. Push it towards 0.3 if the watermark needs to be unmistakable, or down to 0.08 for something subtle.
Can the watermark be removed by someone else?
Yes. It is drawn as ordinary page content, so anyone with a PDF editor can take it out. Treat it as a clear label of intent, not as security or copy protection.
Can I use an image or logo instead of text?
Not in this tool — it handles text watermarks only. An image watermark needs a different approach and may be added later.
Why is my watermark cut off at the edge?
The text is too long or too large for the page at that angle. Shorten the text or reduce the font size — a diagonal watermark has more room than a horizontal one, so an angle around 45° helps too.
Does the watermark go on every page?
Yes, all pages get the same watermark. If you need it on only some pages, split those pages out first, watermark them, then merge the document back together.
Is my file uploaded?
No. The watermark is applied in your browser and your document never leaves your device.