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PDF Overlay

Overlay one PDF onto another. Perfect for watermarks, letterhead, stamps, and combining document layers — 100% private, no upload required.

Files stay on your device
100% Browser-based
No account needed

Base PDF

Drop the base PDF here

This will be the background document

Overlay PDF

Drop the overlay PDF here

This will be placed on top

Frequently Asked Questions

What can I use PDF overlay for?

PDF overlay is commonly used for adding watermarks (confidential, draft, or approved stamps), applying company letterhead to documents, superimposing signatures or seals, and combining multiple document layers into a single PDF.

How does opacity work?

Opacity controls how transparent the overlay PDF appears on top of the base PDF. At 100% the overlay is fully opaque and completely covers the base. At lower values the base PDF shows through, creating a watermark effect.

What happens if the overlay has fewer pages?

If the overlay PDF has fewer pages than the base PDF, the last overlay page is repeated for all remaining base pages. This is useful for applying the same watermark or letterhead to every page of a multi-page document.