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A careful PNG-to-PDF or JPG-to-PDF workflow keeps page images on your device, preserves their intended order, and ends with a check of the finished document.
Read guide →Add Watermark to PDF
Stamp a text watermark on every page of a PDF. Choose font size, colour, opacity, and rotation. Runs in your browser — no upload, no sign-up needed.
Drop a PDF here or click to browse
This PDF is processed in your browser and is not uploaded to opentools.
Reviewed 2026-07-12
Free Add Watermark to PDF – how it works
Add Watermark to PDF overlays a text stamp — such as "CONFIDENTIAL", "DRAFT", or your company name — on every page of a PDF document, entirely in the browser. The watermark is centred on each page and scaled so it stays on-page regardless of font size or rotation angle.
The watermark is added by pdf-lib and is embedded as real PDF text on top of existing page content. It is vector-based, not a raster overlay, which means it scales cleanly at any zoom level and prints sharply.
Use the opacity slider to set how visible the watermark is — from a subtle 10% hint to a fully opaque 100% stamp. Combine with the rotation control (horizontal, 45°, or -45°) to achieve the diagonal watermark look common in legal and financial documents.
How to use Add Watermark to PDF online
- Upload the PDF. Drop your PDF into the tool. It is processed entirely in your browser.
- Configure the watermark. Enter the watermark text. Adjust font size, colour, opacity, and rotation angle. The live preview shows page 1 with your settings applied in real time.
- Apply and download. Click Add Watermark to stamp every page and download the result. Open it to confirm the watermark appears correctly.
When to use it
- Mark a draft document with "DRAFT" before distributing for review.
- Stamp "CONFIDENTIAL" on sensitive reports before sharing externally.
- Add a company name watermark to PDFs before sending to clients.
- Mark approved documents with "APPROVED" and a date stamp.
Known limitations
- The watermark is added as a PDF text layer. It can be removed by someone with PDF editing software — use the Redact PDF tool if you need tamper-proof marking.
- Watermark text is rendered in Helvetica. Custom fonts are not currently supported.
- The live preview shows only page 1. The same watermark is applied to all pages (or a specified range) in the output.
Frequently asked questions
Is Add Watermark to PDF free?
Yes, completely free. No account, no limit, and no watermark from opentools is added to your output.
Are my files uploaded to add a watermark?
No. The watermark is applied using pdf-lib running in your browser. Your PDF is never sent to a server.
Can I watermark specific pages only?
Yes. Leave the pages field blank to watermark all pages, or enter a range like "1-3, 5" to watermark only those pages.
Can someone remove the watermark?
The watermark is a PDF text layer and can be removed by someone with PDF editing software. For permanent, tamper-proof redaction, use the Redact PDF tool instead.
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