This tool adds a diagonal, semi-transparent watermark — DRAFT, CONFIDENTIAL, or any text you type — to every page of a PDF, free, with no daily limit.
Type your text and it's baked diagonally across every page. Nothing is re-compressed — the existing text and images are untouched.
By ShinobiTools Team · Last updated: August 2026
Your file never touches our disk. This tool works entirely in memory and hands the result straight back in the same response — unlike the other tools on this site, there is no 45-minute copy sitting on our server afterwards, because none is ever written.
This tool works entirely in memory and hands the result straight back in the same response — there is no copy sitting on our server afterwards, because none is ever written.
Here is how to add a watermark in PDF files: type the word, drop the file, download. You do not need Acrobat or another paid PDF editor. The text you type is written once on every PDF page, starting at the centre and running up towards the top-right corner at 45°. It is black 40 pt Helvetica at 15% opacity, so the page underneath stays readable, and it becomes part of the page content itself rather than a separate comment layer that a viewer can hide. Pages that already hold images or tables are fine: the new text sits on top without touching either. Keep the text short: at that size one or two words fit on an A4 or Letter page, while a long line such as CONFIDENTIAL DO NOT DISTRIBUTE runs off the edge.
Need the opposite, a watermark taken off instead of added? This tool cannot do that; see the question about removing one below. Want page numbers as well as a stamp? Run the result through Add Page Numbers to PDF next.
One PDF file per upload. To watermark PDF documents in bulk, join them with Merge PDF first, watermark the combined file, and split it again with Split PDF if you need separate files.
A diagonal mark is harder to crop out of a photo or screenshot of the page than a line in the header, and the low opacity keeps the document legible, the same convention as a stamped legal draft. DRAFT and CONFIDENTIAL are the usual choices, but the field takes any word, such as a company name or SAMPLE. The font only covers Latin letters (accents like é and ü work); Chinese, Arabic or Cyrillic characters come out as question marks.
Drop the PDF in, type the text you want stamped (CONFIDENTIAL, DRAFT, a company name) and press Add watermark. The download has that text baked diagonally into every page. That is all there is to how to make watermark in PDF files.
Yes. It is drawn at 15% opacity so the page underneath stays fully readable, the same look as a stamped legal draft.
No, and that is the point. It is drawn as real page content, not a layer that a viewer toggles off, so it stays on the page the same way the rest of the text does.
No. The page's existing content is untouched; the watermark text is added on top, and nothing already there is re-drawn or re-compressed.
Yes. Type anything you like before dropping the file; there is no fixed list of presets. Latin letters work, including accents; Chinese, Arabic or Cyrillic characters don't.
25 pages and 250 MB per file on the free tier, or 200 pages and 500 MB with a pass. There is no account and no daily cap, and nothing is stored on our server afterwards.
Yes, it is free, with no account, no sign-up and no daily cap. You can watermark a PDF online from Safari or Chrome on a computer or a phone, because the watermark is stamped on our server; it is a PDF tool with nothing to install.
Yes. Type DRAFT for a draft watermark or CONFIDENTIAL for a confidential watermark; either way it is the same diagonal stamp on every page. That is how to add watermark in PDF document reviews, or with any other word you choose.
Yes. A scanned page gets the same diagonal text as a digital one, printed on top of the scan image.
One PDF per upload. To watermark PDFs in bulk, join them with Merge PDF first, watermark the combined file, and split it again with Split PDF if you need separate files.
No. Adding watermark to PDF files leaves a normal PDF; the PDF watermark simply becomes part of the page content.
No, this stamps text only, so you can't add image to PDF pages, add picture to PDF files or add photo marks as a watermark here. If you want to add a picture as a page of its own, turn the picture to PDF with JPG to PDF (any image to PDF works) and merge it in.
This tool repeats one short phrase diagonally on every page. To add a line of text to one spot on a single page, or to add notes and comments, use Annotate PDF, which places free text or sticky notes exactly where you click.
Not on this page; it only stamps marks on. If you want to remove watermark from PDF pages you made yourself, such as an old DRAFT stamp, export the original document again without it, which is cleaner than any remover. To remove the stamp from a file that isn't yours, ask whoever made it: we don't offer a way to remove PDF watermark marks from other people's documents.
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