Watermark PDF
Watermark PDF stamps a diagonal text watermark across every page with pdf-lib, entirely in your browser, with no Adobe Acrobat and no signup.
Drag and drop, or click to upload a PDF
PDF file · processed on your device, never uploaded
At a glance
- Accepts
- One PDF file plus the watermark text
- Outputs
- The same PDF with a diagonal watermark on every page
- Where it runs
- Entirely in your browser, on your device
- What leaves your device
- Nothing - the file never leaves your device
- Limits
- No size or count cap; bounded by your device's memory
- Account
- Not required - there is no sign-up
- Price
- Free, with no watermark and no usage cap
- Made by
- Visrut
- Last updated
- 9 October 2026
Watermark PDF stamps your text diagonally across every page of a PDF at a light opacity - no Adobe Acrobat or other software required. It runs on pdf-lib entirely inside this browser tab; the file you upload is never uploaded to a server.
How to use it
- Drag and drop, or click to upload a PDF.
- Type the watermark text, like CONFIDENTIAL or DRAFT.
- Click "Add watermark & download" to save a copy with the watermark on every page.
Frequently asked questions
Is my PDF uploaded to a server?
No - the watermark is drawn entirely in your browser using pdf-lib. The file you upload never leaves your device.
Where does the watermark appear?
Diagonally across the center of every page, at a light opacity so the original content stays readable underneath.
Can I use an image or logo instead of text?
Not yet - this tool only adds a text watermark.
Can I change the watermark's color, size, or angle?
Not yet - it's a fixed gray, 45-degree, semi-transparent watermark. Only the text itself is customizable.
Does adding a watermark reduce PDF quality?
No - pdf-lib draws the watermark text directly onto each existing page without re-rendering or recompressing anything else on it.
What's the watermarked file called?
Your original filename with -watermarked added, like report-watermarked.pdf.