Add Watermark in PDF
Stamp DRAFT, CONFIDENTIAL or your own logo across every page. The document never leaves your browser.
Document
2- to leave a cover clean.
Your watermarked PDF is ready
The download starts automatically. Use the button if it does not.
Runs in your browser. Neither the document nor the logo is uploaded.
How to watermark a PDF
Open the document, type the word you want or choose a logo, and set the opacity, angle and size. The page diagram beside the controls updates as you go, which is how you decide whether fifteen per cent is subtle enough to read through or too faint to notice.
Once, centred puts a single mark diagonally across the middle of each page — the classic DRAFT stamp. Tiled repeats it in a grid, which is harder to crop out of a screenshot and is the better choice for a document you expect to be photographed rather than forwarded.
Choosing an opacity
The default of fifteen per cent is deliberately low. A watermark has to lose an argument with the text underneath it: if it is dark enough to be striking on its own, the document becomes hard to read and people start sending round the unmarked version instead. Somewhere between ten and twenty-five per cent is legible without getting in the way. Above about forty, check the preview on a page of dense text before committing.
A watermark is a label, not a lock
This is worth being plain about. A watermark is drawn on top of the page content and can be removed by anyone with the right software — that is true of every watermarking tool, not this one in particular. What it does well is make status unmistakable: nobody circulates a page stamped DRAFT by accident, and nobody claims they thought a page marked CONFIDENTIAL was public. If a document genuinely must not be altered, sign it or restrict it in a reader that supports permissions.
Text or image
| Text | Image | |
|---|---|---|
| Best for | DRAFT, CONFIDENTIAL, a name or a date | A company logo or a signature block |
| File growth | Almost none — standard fonts are never embedded | One copy of the image, reused on every page |
| Transparency | Set by the opacity slider | PNG transparency is kept, plus the slider |
| Colour | Any colour you pick | The image's own colours |
PNG is the better image format here. A JPG has no transparency, so a logo saved as one arrives inside a white rectangle that hides the page beneath it, and no amount of opacity fixes the box — it only makes the whole thing fainter.
Where the logo goes
Nowhere. It is read by the browser, embedded into the document in memory, and written into the file you download. Like the PDF itself, it is never sent anywhere, which matters because a company logo and a confidential document travelling together is exactly the pairing worth keeping off other people's servers.
Pages and rotation
Leave the pages box empty to mark everything, or type a range: 2- skips a cover, 1, 4, 9 marks three specific pages. The mark is centred on the page as the reader sees it, so a document mixing portrait and landscape pages is stamped consistently rather than having the landscape ones marked off to one side.
Questions
Is my confidential document uploaded to watermark it?
No, and that is the point of building this tool the way it is built. The document is opened and stamped inside your browser, and the logo image never leaves the device either. There is no backend, so nothing is transmitted and nothing is stored.
Can the watermark be removed by someone else?
Yes, with effort. A watermark is drawn on top of the page content, so it can be stripped by anyone with the right software, exactly as with every other watermarking tool. Treat it as a clear label of intent and status, not as a security control. If a document must not be altered, sign it.
Should the watermark go behind the text or over it?
Over it, at a low opacity, which is what this tool does. Drawing behind existing content only works when the page has an opaque white background, and scanned pages and coloured layouts would hide the mark completely. Around fifteen per cent opacity stays readable underneath while remaining unmistakable.
What image formats can I use for a logo?
PNG and JPG. PNG is the better choice because its transparency is preserved, so a logo on a transparent background sits on the page rather than inside a white box. The image is embedded once and reused on every page, so a hundred page document costs one copy of it.
Can I watermark only some pages?
Yes. The pages box takes a range such as 2-, which leaves a cover page clean, or a list like 1, 4, 9. Leave it empty to mark every page.
Why is the tiled option slower on a long document?
Tiling repeats the mark across the page, so a document of a hundred pages can carry a few thousand drawing operations rather than a hundred. It is still quick, and the progress bar reports honestly as it works through the pages.
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