Watermark PDF
Stamp a text watermark such as DRAFT or CONFIDENTIAL across every PDF page with control over opacity, angle, size and colour. Free and fully in-browser.
What is the Watermark PDF?
The ByteTools PDF Watermarker stamps custom text — CONFIDENTIAL, DRAFT, a client name, a date — across every page of a document.
- Any text you like, on every page in one pass
- Opacity from a faint 5% wash to a solid 100% stamp
- Rotation from −90° to 90°, including the classic diagonal
- Five colours, bold or regular, and three page positions
- Vector text stays sharp at any zoom or print size
- 100% private — the document never leaves your browser
How to use the Watermark PDF
- 1
Drop your PDF onto the upload area.
- 2
Type the watermark text, for example CONFIDENTIAL or DRAFT — DO NOT DISTRIBUTE.
- 3
Set the font size, colour, weight and where on the page it sits.
- 4
Adjust the opacity and rotation sliders — 20% at 45° is the classic look.
- 5
Click Add Watermark and download the stamped PDF.
About the Watermark PDF
The ByteTools PDF Watermarker stamps custom text — CONFIDENTIAL, DRAFT, a client name, a date — across every page of a document. You control the font size, colour, opacity and rotation angle, so the mark reads clearly without burying the content underneath it.
The watermark is drawn as real vector text with pdf-lib, entirely inside your browser. Your file is never uploaded, which matters when the document you are marking as confidential is genuinely confidential.
Agencies use it to protect draft deliverables, photographers to mark proofs, legal teams to label privileged copies, and finance teams to flag unapproved figures before a report circulates. Because the mark is applied to every page in one pass, nobody can quietly detach a single sheet and pass it off as final.
Frequently asked questions
How do I add a CONFIDENTIAL watermark to a PDF for free?
Drop the PDF into this tool, type CONFIDENTIAL, set the opacity to around 20% and the rotation to 45°, then click Add Watermark. Every page is stamped and the finished file downloads instantly, with no account and no watermark from us.
Can the watermark be removed by someone else?
A text watermark is drawn into the page content, so it is not a security feature — someone with the right software can strip or cover it. Treat it as a clear label of intent, not as protection against a determined copier.
What opacity should a PDF watermark use?
Between 10% and 25% is the sweet spot: obvious enough to be unmistakable on screen and in print, faint enough that the text underneath stays comfortable to read. Push to 40% or more only when the mark must dominate.
Can I add an image or logo as a watermark?
This tool handles text watermarks only. For a logo, place the image on your pages before exporting to PDF, or overlay it in a page-layout application — text stamping keeps the file small and the mark perfectly sharp at any zoom.
Does watermarking change the rest of the PDF?
No. The existing pages, fonts and images are untouched; the watermark is drawn on top as an extra layer of vector text. File size grows by only a few kilobytes.
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