PDF叠加

What Is PDF Overlay?

PDF overlay places one PDF document on top of another, combining their visual content on the same pages. Unlike merging (which concatenates pages sequentially), overlaying stacks content from two sources onto the same page.

This is used for adding letterheads, applying templates, combining form data with pre-printed forms, or layering any two PDF documents together.

How to Overlay PDFs

1. Upload base PDF and overlay PDF files.
2. Align overlay position and scaling.
3. Adjust opacity if needed for transparency effect.
4. Click 'Apply' to merge and download.

Features

• Overlay one PDF on top of another
• Position and scale overlay independently
• Opacity adjustment for blending effects
• Page-by-page overlay application
• Batch overlaying for multiple documents

Common Use Cases

• Adding a company letterhead or border template to plain PDF documents
• Overlaying filled form data onto a pre-printed form template
• Adding certification stamps or approval seals to document pages
• Combining a watermark pattern with document content

Why Use This Tool?

• Combine two PDF layers — like content and a letterhead template — onto the same pages
• Position and scale the overlay independently from the base document
• Opacity control creates transparent overlay effects
• Apply overlays to all pages or specific page ranges

How It Compares

Adobe Acrobat supports PDF overlay through its combine files features, but the workflow is not intuitive and requires a paid license. Most online tools handle merging but not true page-on-page overlaying.

This tool provides dedicated overlay functionality with position, scale, and opacity controls, processed entirely in your browser.

Tips

• Use overlays to add logos or watermarks to batch documents
• Adjust opacity to make overlay content semi-transparent
• Perfect for merging forms with pre-printed documents

Frequently Asked Questions

How is overlay different from merging PDFs?

Overlay places one PDF on top of another with positioning control. Merging combines pages sequentially.

Can I apply different overlays to different pages?

Yes. You can apply different overlays to specific page ranges in your base PDF.

Is overlay processing done locally on my device?

Yes. All PDF overlay operations happen in your browser with no data sent to any server.

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