PDF Watermark guide
Place a centered diagonal text watermark on every page of a PDF and download a new marked copy.
What this tool does
The PDF Watermark tool opens a selected document locally, embeds a standard bold Helvetica font, and draws the same text near the center of every page. You can choose a font size from 12 to 120 points and an opacity from 5% to 80%. The watermark uses a gray color and a fixed 35-degree rotation so it remains visually separate from most horizontal page content.
Text is limited to 80 characters to reduce accidental overflow. The selected source is not overwritten; the browser generates a separate PDF for download. Existing pages, page order, and page content are retained, but adding drawing commands and an embedded font can change the file size.
A visible watermark is a communication aid, not access control or digital-rights management. Someone with PDF editing software may be able to remove or cover it. It does not encrypt the document, prevent copying or printing, prove authorship, create a certified signature, or guarantee confidentiality.
How to use it
- Choose one unencrypted PDF within the displayed file-size limit.
- Enter a short label such as “DRAFT,” “SAMPLE,” or an authorized recipient name.
- Adjust opacity and font size so the label is visible without hiding essential content.
- Select Apply watermark.
- Download the new PDF and inspect several pages, including pages with different sizes or orientations.
Use neutral, accurate wording. Do not add ownership, approval, confidentiality, or legal-status claims that you are not authorized to make. Keep the original PDF and distribute the marked copy only to intended recipients.
Benefits
- Applies one consistent label to every page
- Offers practical size and opacity controls
- Leaves the original selected file unchanged
- Reports processed page count and output size
- Performs PDF editing locally in the browser
Security and document review
Watermarks can discourage casual reuse and distinguish a draft from a final copy, but they are easy to misunderstand. Protect sensitive documents with appropriate access controls, encryption, retention rules, and recipient verification rather than relying on a visible label.
The fixed center position may overlap important material, signatures, diagrams, or accessibility content. Review the whole result before publication. Password-protected, damaged, or unusually complex PDFs may not open correctly.
Practical notice: A visible watermark is not a security control, certified signature, copyright determination, or legal restriction.