Add watermark
Overlay custom watermark text or image to secure or brand your documents.
or drag & drop here
Supports PDF documents up to 50MB. Processed 100% securely inside your browser.
Add Watermark to PDF — Protect & Brand Your PDF Online
Introduction
Protecting your intellectual property and ensuring document confidentiality is vital when sharing sensitive PDF files. Adding a watermark — whether it's your company logo, a "Confidential" stamp, or a "Draft" notice — serves as a powerful visual deterrent against unauthorized use and clearly identifies the status of your document. PDFscaler provides a free, secure Add Watermark online tool that allows you to overlay custom text or images onto your PDF pages in seconds.
Our watermarking utility is built with ease of use and professional control in mind. You can fully customize the text content, font size, color, opacity, and rotation angle to achieve the perfect look for your document. Most importantly, all processing occurs 100% locally in your web browser, ensuring that your confidential business plans, creative drafts, and personal documents remain completely private.
What This Tool Does
The Add Watermark tool programmatically modifies the content streams of your PDF pages to include new graphical or text elements. When you upload a document, our engine calculates the coordinates for your watermark based on the page dimensions and your selected settings.
The engine uses WebAssembly-powered PDF manipulation to inject a new Transparency Group (/Trans) layer into each page's resource dictionary. This allows the watermark to sit behind or on top of your text with adjustable transparency, ensuring it remains visible without obscuring the underlying content. Because the operation happens entirely in local memory, your document is processed and ready for download instantly without any network transmission.
Why Use This Tool
Key Features
See How It Works
Watch how your documents and media are processed step-by-step with zero server uploads.
⚡ Instant Results
Zero wait client execution
🔒 100% Private
Files stay in your browser
💻 Cross Platform
PC, Mac, iPhone & Android
✨ HD Quality
Lossless document output
Privacy & Security Guarantee
Data confidentiality is a core principle at PDFscaler. Documents requiring watermarks often contain proprietary business information, legal drafts, or sensitive personal content. When you use our Add Watermark tool, all processing executes locally inside your browser tab memory sandbox. Your files and watermark entries are never sent over the internet, stored on external servers, or accessed by third parties. This architecture provides a robust, private environment for securing your most important documents.
Common Use Cases
Corporate Confidentiality
Businesses marking internal strategy documents as "Confidential" to prevent leaks.
Creative Portfolio Protection
Designers and photographers adding status text to draft PDFs to protect their intellectual property.
Legal Drafts
Attorneys marking agreement versions as "Draft" for client review and revision.
Sample Documents
Sales teams watermarking product manuals and brochures as "Sample" for prospects.
Copyright Marking
Authors and content creators adding copyright notices to digital manuscripts.
Invoice Verification
Accounts teams marking invoices as "Paid" or "Pending" for internal records.
Frequently Asked Questions
Q:Is the Add Watermark tool free on PDFscaler?
Yes, our watermarking tool is 100% free with no subscription traps or watermarks of our own.
Q:Can I adjust the transparency of the watermark?
Yes, you can use the opacity slider to make your watermark as subtle or as prominent as you need.
Q:Can the watermark be easily removed by others?
Our engine embeds watermarks directly into the PDF content stream, making them much harder to remove than simple overlays.
Q:Are my confidential documents uploaded to a remote server?
No, all watermarking logic executes locally in your browser memory for absolute privacy and security.
Q:Can I add an image as a watermark?
Currently, our tool supports highly customizable text watermarks. We are working on adding image support soon.
Q:Does Add Watermark work on mobile devices?
Yes, PDFscaler works smoothly on mobile browsers including Safari on iOS and Chrome on Android.
Q:Will adding a watermark reduce my PDF quality?
No, our tool uses high-quality vector rendering that maintains the crispness of your original document.
Q:Can I rotate the watermark text?
Yes, you can set any rotation angle (e.g., 45 degrees diagonal) to suit your document style.
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