Interleave PDF: Merge Front and Back Scans

Merge the front and back pages of a double-sided document scanned on a single-sided scanner into one PDF in the right order, with the backs reversed. Free.

The file is read by your browser and is not sent anywhere. No upload, no storage.

What it does


A scanner with a single-sided feeder scans all the fronts of a stack, and then, after you turn the stack over, all the backs, from the last to the first. This tool puts them back together as front 1, back 1, front 2, back 2 and so on, from two files or from one file that has all the fronts followed by all the backs.

How to use it


  1. Choose whether the scans are in two files or one, and choose the PDF or PDFs.
  2. Keep Reverse ticked if you turned the stack over to scan the backs, and check the new order.
  3. Click Interleave pages and download the PDF in order.

Frequently asked questions


How do I combine odd and even pages into one PDF?
Choose the file with the odd pages (fronts) and the one with the even pages (backs). With 3 sheets scanned this way the result is 1, 2, 3, 4, 5, 6.

Why are the backs reversed?
When you turn the stack over, the last sheet is scanned first. With Reverse ticked, the backs 6, 4, 2 scanned in that order go back to 2, 4, 6.

What if one side has more pages?
The pages are paired as far as they go and the extra pages of the longer side are added at the end, so nothing is lost.

βž• Merge PDF
⇄ Organize PDF Pages
βœ‚ Split PDF
β–¦ Multiple Pages per Sheet (N-up PDF)