Add a watermark to a PDF
Protect or label your documents with a semi-transparent text stamp on every page — diagonal “CONFIDENTIAL”, a copyright line, a client name. You control the text, size, color, opacity and angle.
How to use the Watermark PDF tool
Select or drag your PDF.
Type the watermark text and adjust style, opacity and position.
Click “Add watermark” and download the stamped PDF.
Your files stay on your device
This tool runs entirely in your browser using JavaScript and WebAssembly. There is no upload step and no server processing — open your network panel and check: zero document data is transmitted. It even keeps working offline once the page has loaded.
Frequently asked questions
Can the watermark be removed afterwards?
The stamp is drawn into each page’s content, so casual viewers and printers always show it. Like any visible watermark, a determined person with editing software could cover it — for legal protection combine it with the Protect PDF tool.
Can I watermark only some pages?
The watermark is applied to all pages, which is what stamps like DRAFT or CONFIDENTIAL are for. If you need it on a subset, split the PDF first, stamp the part you need, and merge back.
Does it support logos or image watermarks?
This tool stamps text. For a logo on every page, a practical route is the Sign PDF tool with your logo image, or tell us — image watermarks are on the roadmap.
Is it safe to use this tool with confidential documents?
Yes — and verifiably so. PDFAgent has no upload step: your file is processed by JavaScript running in your own browser and never leaves your device. You can open your browser’s network panel (or even go offline after loading the page) and confirm that no document data is transmitted.