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Add a watermark to a PDF online — text or brand, free and private
Want to mark a draft as 'CONFIDENTIAL', or put your brand on every page? Add Watermark to PDF stamps text (or a logo) across your document in the browser — no upload, no install.
Text watermark
Type the words (a name, 'DRAFT', a copyright line) and choose placement: tiled across the page, centered as a single mark, or in a corner. Set the font size, opacity and a slight angle so it reads as a mark, not a banner.
Logo watermark
For a brand, upload a logo image and it's drawn on each page. A PNG with transparency keeps the mark clean. Lower the opacity so the text underneath stays readable.
Stays on your machine
The PDF is read and re-saved locally with pdf-lib. Confidential documents are never sent to a server — important precisely because watermarks usually mean the file is sensitive.
Frequently asked questions
Can I watermark every page at once?
Yes. The watermark is applied to all pages by default; you choose tiled, centered or corner placement.
Will the watermark cover the text?
Only if opacity is too high. Keep it around 25-40% so the content stays readable underneath.
Is my document uploaded?
No. Watermarking runs in your browser; the PDF never leaves your device.