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Interleave two PDFs in alternate page order

Combine a stack of front scans and a stack of back scans into one document. Pages alternate from the first and second PDF, with an option to reverse the back stack.

Your PDFs are processed on this device. File contents and names are not uploaded or logged.

How it works

  1. Choose two PDFs: front pages first, back pages second. Use Move up or Move down to change the file order.
  2. Select Reverse second PDF if the back pages were scanned in reverse order. Decide whether unequal stacks should stop or keep the extra pages.
  3. Choose Interleave PDFs, download the result and check the page sequence before printing.

How alternate-page merging works

For first-stack pages 1, 3, 5 and second-stack pages 2, 4, 6, the result is 1, 2, 3, 4, 5, 6. If the second scan runs 6, 4, 2, reverse that stack before interleaving. This changes page order without rasterizing the PDF.

Unequal stacks never lose extra pages

The default stops when the two PDFs have different page counts so you can check a missing scan. Choose Append remaining pages to keep unmatched pages at the end in their selected stack order. No blank pages are inserted and no unmatched page is discarded.

Supported scan PDFs

This tool accepts ordinary, unencrypted PDFs within the device limits. It preserves page size, crop boxes, rotation and page content. Interactive forms, annotations, bookmarks, attachments, tagged PDFs and other advanced document structures are rejected rather than partly copied. Flatten a copy first if losing interactivity is acceptable.

Frequently asked questions

How is this different from Merge PDF?

Merge PDF puts one whole document after another. Interleave PDF takes one page from each stack in turn, which is useful for separate front and back scans.

Which file supplies the first page?

The first file in the list supplies the first page. The second supplies the next page. Move the files up or down before processing if necessary.

Will the output change the scan quality?

Pages are copied rather than rendered to images, so this tool does not intentionally recompress the scan images. PDF structure and metadata may change when the new document is saved.

Can I reverse the first PDF too?

This tool reverses the second stack only. Reorder the first PDF in Organize PDF before interleaving if it also needs reversing.

Last reviewed: October 16, 2026

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