Stamp it CONFIDENTIAL — without uploading it anywhere
Drop a PDF above, type a stamp like DRAFT or CONFIDENTIAL (or upload a logo), position it on the nine-point grid or tile it diagonally across every page, and download the marked copy. The output stays a true vector PDF — your text remains selectable and sharp — and the whole job runs on your device: contracts, invoices, and manuscripts are never uploaded to a server.
Fine-tune opacity so the mark sits behind the reading experience instead of on top of it
(20–35% works for most documents), rotate it to the classic 45° diagonal, and scale it
relative to the page width so portrait and landscape pages both look right. A page range like
1-3,5 lets you stamp only the pages that need it.
A watermark deters casual reuse but is not a security boundary — anything drawn on top of a page can be lifted off by determined editing. When content must actually be unrecoverable, redact the PDF instead. Locked files need Unlock PDF first, images want the image watermark tool, and if the stamped file needs filling out afterwards there is Fill PDF Form. Bulky output compresses well with the PDF compressor.
Frequently asked questions
Is my PDF uploaded to a server?
No. The file is opened, previewed, and stamped entirely in your browser using pdf.js and pdf-lib. Neither the PDF nor your watermark text or logo ever leaves your device — which matters, because documents worth watermarking are usually documents worth keeping private.
Does the watermark stay selectable text, or is the PDF rasterized?
The output stays a real vector PDF. The watermark is drawn as native PDF text (or an embedded image) on top of your existing pages, so the original content remains selectable, searchable, and exactly as sharp as before. Nothing is converted to a screenshot.
Can someone remove the watermark later?
A determined person with PDF editing software can remove any overlay watermark — that is true of every watermark tool, including Adobe’s. A watermark is a deterrent and an attribution mark, not a security measure. If you need content to be unrecoverable, that is redaction, not watermarking — use our Redact PDF tool for that.
What is the difference between the 9-grid positions and tiling?
A grid position stamps the mark once per page — for example bottom-right for a logo, or dead center for a DRAFT stamp. Tiling repeats the mark diagonally across the whole page on a staggered grid, the classic look for CONFIDENTIAL backgrounds, so cropping a corner cannot remove it.
Why does my password-protected PDF fail to load?
Encrypted PDFs cannot be modified without decrypting them first. If your file needs a password to open, run it through our Unlock PDF tool first, then watermark the unlocked copy.
Can I watermark only some pages?
Yes — the page range field accepts entries like "1-3,5". Leave it empty to stamp every page. Out-of-range entries are flagged and skipped rather than failing the whole job.