Watermark PDF Without Uploading

This tool stamps text of your choice across every page of a PDF, at the angle, size and opacity you pick, and it does so in your browser: the document is opened in memory, the text is drawn into each page's content, and the result is handed back as a download. Confidential drafts are the most-watermarked documents there are, which makes local processing the whole point.

A watermark answers a social problem more than a technical one: it makes the status of a document unmissable. DRAFT on a version that must not be signed, CONFIDENTIAL on a deck that will be forwarded anyway, SAMPLE on work sent before payment, a client's name on a copy so leaks identify their channel. None of this stops copying; all of it removes the excuse of not knowing.

Where the mark lands matters. A pale diagonal across the body is read on every page and survives photocopies and screenshots taken carelessly. Corner marks are politer but crop out. Opacity is a trade: 10 to 20 percent whispers under the text without hurting readability; 40 percent shouts on presentation covers. The tool draws the watermark INTO the page content, not as a removable annotation layer, so casual removal by 'delete annotation' does not work.

Honesty about limits: a determined adversary with editing tools can reconstruct pages and scrub a watermark, and nothing drawn on a page prevents retyping the words. A watermark is a seatbelt, not a vault; for control you would need encryption and for proof of origin a digital signature, both different tools for different threats.

Craft notes from real use: stamp AFTER final edits, because re-exporting from an editor can flatten or duplicate marks; check page 1 and one middle page at full zoom before sending; on scanned documents, a light watermark can disappear into grey backgrounds, so raise opacity a step. Encrypted files must be unlocked first, like everywhere on this site.

The output remains a normal PDF: text under the watermark stays selectable, files can still be merged or compressed afterwards, and file size grows only trivially, since a text stamp is a few kilobytes of drawing instructions, not an image per page.