Watermark PDF
Add a text watermark to every page of your PDF, right in your browser. Type your text, set the opacity, and download. Need to shrink the file after? Try our PDF compressor or combine files with the PDF merger.
Watermark PDF
Upload a PDF, set your text and opacity, then stamp every page
What is PDF Watermarking?
PDF watermarking is the process of stamping text over the content of every page in a PDF (Portable Document Format) file. A watermark is typically a word or short phrase, such as CONFIDENTIAL, DRAFT, or SAMPLE, drawn diagonally across the page at a reduced opacity so the underlying content stays readable. According to MDN Web Docs, PDF page content is drawn as vector and text objects, which means a watermark can be added directly to each page.
Watermarking is useful for many reasons: marking documents as confidential or internal, labeling drafts so they are not mistaken for final versions, adding ownership or copyright notices, discouraging unauthorized copying, and branding proposals or reports. Because the watermark appears on every page, the label travels with the document no matter which page a reader lands on.
This tool uses pdf-lib, a powerful JavaScript library, to add your watermark entirely in your browser. This client-side processing keeps your PDF completely private and secure. All work happens locally, so your documents never leave your device or get uploaded to any server.
✗Before Watermarking
A plain PDF gives no visual signal about its status. Readers cannot tell at a glance whether a file is a draft, a confidential document, or a sample copy.
document.pdf
No status label on the pages
✓After Watermarking
Every page carries your text, such as CONFIDENTIAL, at the opacity you chose. The document is clearly labeled and ready to share, print, or archive.
watermarked-document.pdf
Text stamped on every page
Why Use This Watermark Tool?
Adding a watermark protects, labels, and brands your documents. Here are the key advantages of using this browser-based tool:
Label Confidential Files
Stamp CONFIDENTIAL, INTERNAL, or PRIVATE across every page so anyone who opens the file understands its status immediately. Ideal for contracts, financial statements, and sensitive reports.
Mark Drafts Clearly
Add a DRAFT or SAMPLE watermark so reviewers never confuse a work in progress with the final version. This prevents costly mistakes when documents move between teams.
Adjustable Opacity
Control exactly how bold the watermark looks with the opacity slider. Keep it faint so the text underneath stays easy to read, or turn it up so the label really stands out.
Privacy and Security
All watermarking happens in your browser using client-side JavaScript. Your PDF files never leave your device, are not uploaded to any server, and are not stored anywhere. Your documents stay private.
Fast and Free
Client-side processing means instant results with no file uploads and no waiting on a server. Watermark documents in seconds, at no cost, with no account and no limits on how many files you process.
Every Page Covered
The watermark is applied to all pages automatically, so you never have to stamp pages one by one. Whether your document has one page or hundreds, each page gets the same mark.
How It Works
This tool uses pdf-lib to draw your watermark directly onto each page in your browser. Here is how the process works:
Upload PDF File
Upload your PDF file. The tool loads it in your browser and displays the number of pages so you know the whole document will be marked.
Set Text and Opacity
Type your watermark text, such as CONFIDENTIAL, and use the opacity slider to choose how strong the watermark looks on the page.
Add and Download
Click Add Watermark to stamp the text diagonally across every page. Once processing finishes, download your watermarked PDF file.
Best Practices for Watermarking
To get the best results when watermarking PDF pages, follow these best practices:
- ✓Keep the text short: Short words like CONFIDENTIAL or DRAFT read clearly at a large size. Long phrases can run off the edge of the page or overlap too much content.
- ✓Balance the opacity: Set a lower opacity when the page text must stay easy to read, and a higher opacity when the label needs to dominate. Try a value around 0.3 as a starting point.
- ✓Keep your original file: The watermark becomes part of the downloaded PDF. Save your original, unmarked file as a backup in case you need a clean copy later.
- ✓Preview before sharing: Open the watermarked PDF and check a few pages to confirm the text and opacity look right before you distribute the document.
- ✓Watermark before other steps: If you plan to compress or merge the file, add the watermark first so the label is consistent across the final combined document.
Frequently Asked Questions
How do I add a watermark to a PDF?
Upload your PDF file, type the watermark text you want (for example CONFIDENTIAL or DRAFT), adjust the opacity slider to control how visible the watermark is, then click Add Watermark. The tool stamps your text diagonally across every page. When it finishes, download your watermarked PDF.
Is the PDF watermark tool free?
Yes, this watermark tool is 100% free. There is no registration, no account, and no hidden fees. All processing happens in your browser, so your files never leave your device and stay completely private.
Does my PDF get uploaded to a server?
No. Everything runs locally in your browser using client-side JavaScript. Your PDF is never uploaded, sent to a server, or stored anywhere. This makes it safe for sensitive contracts, invoices, and confidential documents.
Can I change how visible the watermark is?
Yes. Use the opacity slider to set the watermark strength from 0.1 (very faint) up to 1.0 (fully solid). A lower opacity keeps the underlying text readable, while a higher opacity makes the watermark stand out more.
Will the watermark appear on every page?
Yes. The watermark text is drawn diagonally across the center of every page in the document, so each page carries the same mark. This is ideal for labeling entire documents as confidential, draft, or sample.
Can I remove the watermark later?
The watermark is drawn into the page content, so it becomes part of the file once you download it. Keep your original PDF as a backup if you may need an unmarked copy later. To use different text or opacity, just re-run the tool on your original file.
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