PDF and documents
PDF Watermark Tool
Add draft, confidential, or brand text to documents
🔒 See this tool’s privacy notes for local processing and external service details. Site analytics are described in our privacy policy.
Quick guide
What can PDF Watermark help you do?
Free PDF watermark tool. Add a text watermark with custom size and opacity. Browser-based, no upload.
Best for
Mark a review copy as DRAFT or add a short company label across every page before circulation. This tool adds a visible text overlay to a new PDF; it is suited to communicating document status, not restricting who can read or copy it.
How to use it
Choose a PDF and enter Watermark text, or keep CONFIDENTIAL. Start with the default font size 48 and adjust Opacity between 0.05 and 0.60. The size control offers 12 to 160. Press Add watermark to generate and download watermarked.pdf.
How to read the result
The same bold, dark-colored text is drawn near the middle of each page at a fixed -35-degree angle. Lower opacity makes it fainter. Open the downloaded file and check both sparse and dense pages; there is no preview or automatic text fitting.
Privacy and limits
The widget uses pdf-lib 1.17.1 from jsDelivr to process PDF bytes and watermark text in the browser. Loading that library contacts the CDN, not a document-upload endpoint. A CONFIDENTIAL label does not encrypt the download or remove sensitive material underneath.
Only text watermarks are offered, with no logo, page selection, color, or angle control. The embedded font supports common Latin characters and rejects CJK or other unsupported text. Long labels can run off the page; a watermark is not redaction or tamper protection.
Frequently Asked Questions
Does it change my original file?
No. A new watermarked PDF is generated.
Is my PDF uploaded?
No. Everything runs in your browser.