Add a watermark to a PDF using this free, browser-based tool that overlays custom text or image watermarks on every page of your document. Adjust the opacity, position, and font size to match your needs, then download the watermarked PDF instantly. No signup is required, and the file is processed entirely in your browser without being uploaded anywhere.
PDF Watermark is a free browser-based tool that adds a text watermark to every page of a PDF file. Users enter the watermark text, choose the font size, color, and opacity, select the rotation angle, and download the watermarked PDF. Watermarks are commonly used to mark documents as drafts, confidential, sample copies, or proprietary materials. They discourage unauthorised distribution by clearly identifying the document's status or owner. The tool uses pdf-lib to embed the watermark directly into the PDF page content, making it part of the document rather than a separate overlay. The output is a standard PDF compatible with all PDF viewers. The tool runs entirely in the browser with no server upload, making it appropriate for use with sensitive documents. No account or installation is required.
PDF Watermark is useful in a range of professional and document management workflows. Legal and consulting firms watermark draft documents to prevent clients from treating preliminary versions as final deliverables. Content creators and photographers watermark sample PDFs to discourage unauthorised use of proprietary materials. HR departments watermark confidential compensation or organisational documents before sharing them with select employees. Educators watermark exam papers or answer keys with student names or identifiers to discourage sharing. The tool provides control over text, size, color, opacity, and rotation angle. A diagonal orientation at 45 degrees with medium opacity is the conventional watermark placement that is clearly visible without obscuring the underlying content to the point of unreadability. The watermark is embedded directly into the PDF page content stream using pdf-lib, which means it appears in all viewers and when printed, and cannot be removed simply by deleting an annotation layer. However, a watermark embedded this way can still be removed by a determined user with the appropriate tools, so it serves as a deterrent rather than a technical security measure. For documents that must not be modified or copied, combining a watermark with PDF password protection provides a stronger barrier. The tool processes files in the browser with no server upload.