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Alternate and Mix Two PDFs

Weave the fronts and backs of a double-sided document back together in the right order.

About Alternate & Mix PDF

Alternate & Mix PDF solves a classic scanner problem. Your feeder scans one side only, so you run the stack through twice and end up with two files, all the fronts and then all the backs, usually in reverse. Upload the fronts as the first file and the backs as the second, and the pages are woven together: front 1, back 1, front 2, back 2 and so on.

Second file is in reverse order is ticked by default, because turning the stack over means the backs come out last page first. Untick it if your backs are already in order. If one file has more pages, the extras are added at the end. The pages keep their quality and the result is saved as a new PDF.

How to use Alternate & Mix PDF

  1. 1
    Add the fronts

    Upload the PDF with the front sides first; it's shown as the first file.

  2. 2
    Add the backs

    Add the PDF with the back sides as the second file.

  3. 3
    Check the order option

    Keep Second file is in reverse order ticked if you flipped the stack to scan the backs.

  4. 4
    Mix and download

    Click Alternate & Mix PDF and save the merged document.

Why use Cubfile for this

  • Double-sided without a duplex scanner

    Scan the fronts, flip the stack, scan the backs, and let the tool sort out the order.

  • Reverse order handled

    Backs that come out last page first are flipped back automatically.

  • Uneven files handled

    If one file has extra pages, they're added at the end instead of being lost.

  • Original quality

    Pages are interleaved as they are, with nothing recompressed.

FAQ

Alternate & Mix PDF: questions and answers

How do I use Alternate & Mix PDF for double-sided scans?
Scan all front sides into one PDF, turn the stack over and scan the backs into a second. Upload fronts first and backs second, keep the reverse option on and run it. If the stack contained several letters, Split PDF can then give each one its own file.
When should I untick Second file is in reverse order?
When the backs are already in page order, for example if you re-sorted the paper before scanning. Then back 1 pairs with front 1 without any flipping.
Can I alternate and mix PDF files that aren't scans?
Yes. Any two PDFs can be interleaved page by page, such as questions and answers or two language versions of a document. For one file placed straight after the other, use Merge PDF instead.
How big can the two scans be?
Each file can be up to 50 MB on the free plan or 1 GB with VIP. Free accounts get 2 tasks a day, visitors 2 in total, and VIP has no limit.
What happens to my scanned documents?
Both scans and the combined PDF are deleted automatically after an hour. They're uploaded over HTTPS and processed where nobody looks at them.
Share Alternate & Mix PDF with a friendIt runs in any browser, and they can try it without signing up.

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