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omegatools
PDF Tools 100% Client-Side Privacy

Add Watermark to PDF Online

Stamp confidential, draft, or copyright text watermarks onto your PDF documents in seconds. Custom positioning, angle, opacity, and full-document protection.

Drag & drop your PDF here, or click to browse

Supports PDF documents up to 50MB • 100% In-Browser Private

How to Use This Tool

How to Use This Tool – Add Watermark to PDF

01

Upload PDF Document

Drag and drop your PDF file or click to select a document from your computer or mobile device.

02

Customize Text & Position

Type your custom watermark text (e.g. Confidential, Draft, Sample) and adjust opacity, rotation, font size, and color.

03

Apply & Download

Preview the watermark over your document pages and download the watermarked PDF instantly with zero server uploads.

Key Features & Capabilities

Key Features & Capabilities – Add Watermark to PDF

Flexible Watermark Positions

Position your watermark in the center, diagonal (-45°), top header, bottom footer, or repeat as a tiled pattern across all pages.

Granular Opacity Control

Adjust transparency from 5% to 100% so text remains readable underneath your protective watermark.

Custom Angle & Font Size

Fine-tune rotation from -90° to +90° and scale text size to fit any document format or orientation.

Multi-Page Batch Application

Stamp every page of your PDF in a single click with consistent alignment and style across the entire document.

High-Fidelity PDF Vector Text

Watermarks are embedded as sharp vector text elements without rasterizing or degrading the original document quality.

100% Private Client-Side Stamping

Your contracts, financial statements, and confidential papers are processed locally in your browser sandbox.

FAQ

Frequently Asked Questions

How do I add a watermark to a PDF online for free?
Simply upload your PDF to our Add Watermark to PDF tool, enter your desired watermark text, choose your preferred rotation angle and opacity, and click download. The file is processed entirely in your web browser.
Will adding a watermark reduce the quality of my PDF text or images?
No. The tool embeds the watermark text as a native vector layer over the existing pages, preserving all original vector text, vector graphics, and high-resolution images.
Can I apply the watermark diagonally across the center of all pages?
Yes! Select the Diagonal Center preset (45° angle) to apply a classic security watermark centered across every page in your document.
Are my confidential documents uploaded to a remote server?
Never. Processing is performed 100% client-side using JavaScript inside your browser. No files or text ever leave your computer or mobile device.
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