HP ToolsHub runs fast client-side utilities. Please enable JavaScript for interactive processing.
Watermark PDF Online Free – Add Text Watermark to PDF | HP ToolsHub

Watermark PDF Online Free

Use Watermark PDF online for free. Fast, client-side processing directly in your browser with zero file uploads to external servers.

Supported Formats & Specifications

PDFJPGPNGWebPSVG

How to Use Watermark PDF Online Free

  1. 1
    Upload PDF Document Select or drag & drop the PDF you want to protect with a watermark.
  2. 2
    Customize Watermark Text Type your stamp text (e.g., "CONFIDENTIAL") and select font size, color, and angle (e.g. 45° diagonal).
  3. 3
    Adjust Transparency Fine-tune opacity so the watermark is clearly visible without obscuring underlying document text.
  4. 4
    Apply & Download Click "Apply Watermark" to stamp all pages and download your protected document.

Key Features & Capabilities

  • ✓ Live Visual Customization — Real-time preview of text size, color, rotation angle, and opacity.
  • ✓ Adjustable Transparency Slider — Prevents watermarks from blocking or covering important document text.
  • ✓ Diagonal & Horizontal Alignment — Choose 45-degree diagonal placement or clean horizontal stamps.
  • ✓ 100% Client-Side Privacy — Documents are stamped locally in your browser with zero server uploads.

Privacy & Local Processing Guarantee

All processing occurs 100% on your device using client-side WebAssembly. No files are uploaded to our servers.

Frequently Asked Questions

Will the watermark make my document text hard to read?

No. You can adjust the opacity slider to 15%–30% so the watermark is distinctly visible as a background security stamp while keeping all text easily readable.

Does the watermark apply to all pages in the PDF?

Yes! The tool automatically applies your customized watermark across all pages in the document simultaneously.