Add watermark to PDF

Add a Watermark to Any PDF, Free, Private, No Upload

This tool lets you stamp any text watermark directly onto your PDF pages, choose the text, font size, opacity, color, and position, then download the result instantly. Everything runs inside your browser using PDF-lib, so the output is a real, modified PDF file, not a screenshot or image overlay.

Your files never leave your device. Nothing is uploaded to any server, no account is required, and there is no file size limit enforced by a backend. You can watermark sensitive contracts, draft documents, or confidential reports without any privacy risk.

How to Add a Watermark to a PDF

1. Open your PDF. Click "Select PDF" or drag and drop the file onto the tool. The document loads entirely in your browser, no upload happens.
2. Set your watermark text. Type the text you want to stamp (e.g. "CONFIDENTIAL", "DRAFT", your company name, or a copyright notice). Adjust the font size, color, and opacity to suit the document.
3. Choose placement. Select whether the watermark appears centered on each page, in a corner, or as a diagonal text across the full page. Apply to all pages or a custom range.
4. Download the watermarked PDF. Click "Apply Watermark" and your browser processes the file locally. The result downloads immediately as a standard PDF, ready to share or print.

Why Use This Tool

• Completely free. No subscription, no credit card, no usage cap. The tool is free for personal and professional use.
• 100% local processing. PDF-lib runs entirely in your browser. Your file is never transmitted anywhere, not to our servers, not to third-party APIs.
• No privacy risk. Watermarking legal documents, HR files, or financial reports carries zero exposure. The file stays on your machine throughout the entire process.
• No watermark added by the tool itself. The only text added to your PDF is what you type. There is no branding, no promotional overlay, no hidden stamp from iSharePDF.
• Unlimited use, any device. Works on desktop, tablet, and mobile browsers in 2026. No installation required, open the page and start immediately.

Common Use Cases

Watermarking is useful in a wide range of professional contexts. A freelancer sending a draft proposal can stamp "DRAFT, NOT FOR DISTRIBUTION" before sharing with a client. A photographer or designer delivering previews can add a copyright watermark to protect work before final payment. A business distributing internal reports can mark each copy "CONFIDENTIAL" to reinforce data handling policies, all without sending sensitive files through an external service.

Frequently Asked Questions

Can I add a watermark to a PDF without Adobe Acrobat?

Yes. This tool handles watermarking entirely in your browser without requiring Acrobat, a PDF editor, or any installed software. It uses the open-source PDF-lib library, which reads and rewrites the PDF structure directly. The output is a fully valid PDF compatible with all standard viewers.

Will the watermark be permanent, or can it be removed later?

The watermark is embedded into the PDF as a content layer, which makes it persistent in standard viewers. It is not easily removed by recipients without dedicated PDF editing tools. For documents where tamper-resistance matters more, such as signed contracts, combining a watermark with a password lock (available in our Protect PDF tool) adds a stronger layer of protection.

Can I watermark a multi-page PDF and apply it to every page?

Yes. By default, the watermark is applied to every page in the document. You can also specify a custom page range if you only want to stamp certain pages, for example, pages 2 through 10 of a report with a cover page you want to leave clean.

Is there a file size limit for PDFs I can watermark here?

There is no server-side file size limit because no file is ever uploaded. The practical limit depends on your device's available memory. Most standard documents, including multi-hundred-page PDFs, process without issue on a modern laptop or desktop. Very large files with high-resolution embedded images may take a few seconds longer on lower-end devices.

Can I add an image or logo as a watermark instead of text?

The current version of this tool supports text watermarks. For image-based watermarks (such as a company logo or signature), this is a feature on our development roadmap. In the meantime, if your logo can be represented as styled text or a simple symbol, the text watermark with adjusted font and opacity often works as a practical alternative for internal document control.