Add watermark
Stamp custom text across every page. Runs in your browser.
Select a PDF to watermark
Upload one PDF document
Processed locally in your browser. Never uploaded.
Stamp Copyright, Confidentiality, and Status Markers on PDFs
Vector text stamping with precision alpha-channel transparency
Protecting unreleased manuscripts, legal discovery documents, financial models, and client proposals requires clear visual indicators like 'CONFIDENTIAL', 'SAMPLE', or 'DO NOT COPY'. Uploading these sensitive drafts to conventional web tools exposes them to cloud retention vulnerabilities and potential corporate espionage.
Modifyle's client-side watermark engine embeds custom vector text across every page of your document directly in browser memory. By calculating exact page viewport dimensions and applying mathematical 45-degree rotational transformations, the watermark is positioned centrally with balanced visual impact.
You have fine-grained control over font sizing, opacity, and brand color palettes, creating clean, professional-looking protection without compromising readability.
How It Works in 3 Simple Steps
Upload PDF
Select the PDF file you wish to protect with a text watermark.
Customize Text & Style
Type your text (e.g. CONFIDENTIAL) and adjust font size, opacity slider, and color.
Stamp & Download
Click Apply Watermark to render the overlay across all pages and download the result instantly.
Why choose Modifyle PDF Watermark Tool?
Frequently Asked Questions
How do I mark a PDF as 'CONFIDENTIAL' or 'DRAFT'?▼
Simply enter your desired text into the watermark input field. You can customize font size, opacity percentage, and brand color. The text is automatically rendered diagonally across the center of each page.
Will the watermark cover or destroy the underlying document text?▼
No. Modifyle applies transparent alpha blending (adjustable between 10% and 80% opacity), ensuring your underlying document text, diagrams, and signatures remain clearly readable while prominently showing the ownership mark.
Can anyone easily remove the watermark using basic PDF readers?▼
Modifyle embeds the watermark stream directly into the PDF content stream with vector typography, making casual removal with consumer readers impossible without specialized editing tools.
Are my draft contracts or sensitive documents safe?▼
Yes, completely. Because Modifyle runs 100% inside your browser using client-side WebAssembly, no document is ever uploaded to a remote server. Confidential business filings and legal agreements remain completely private.