FoxletPDF by MetaFox

Alternate & Mix

Scanned the fronts and backs of a stack separately? Mix the two PDFs page by page into one correctly ordered document.

  • Free, no signup
  • No watermark
  • Files never leave your device

1. Front sides (odd pages)

Pages 1, 3, 5… — usually the first pass through the scanner.

or drop it here

2. Back sides (even pages)

Pages 2, 4, 6… — the second pass.

or drop it here

Add both PDFs to continue.

How to combine front and back scans

  1. Add the front sides. Choose the PDF with pages 1, 3, 5… — the first pass through your scanner.
  2. Add the back sides. Choose the PDF with pages 2, 4, 6… — the second pass.
  3. Check the order option. If you flipped the whole stack to scan the backs, they come out last-to-first. Keep “reverse order” ticked to fix that.
  4. Mix and download. Select “Mix PDFs” and save your complete document.

Tips for double-sided scanning

  • Blank backs? Scan them anyway so pages pair up, then remove blanks with Delete Pages.
  • Different page counts. Pages are still alternated; extra pages from the longer file go at the end.
  • Not a scan? You can mix any two PDFs, for example to interleave questions and answers.
  • Check the result. Flick through the first few pages to confirm the order before you share it.

Your files stay on your device

Like every FoxletPDF tool, this one runs inside your browser. Your file is read from your device, processed with open-source PDF libraries (pdf-lib and PDF.js), and handed straight back to you as a download. Nothing is uploaded, logged or stored. See our privacy policy for details.

Frequently asked questions

Are my scans uploaded?

No. The PDFs are combined in your browser and never leave your device.

Why would the backs be in reverse order?

When you turn the whole stack over to scan the back sides, the last page is scanned first. The reverse option corrects this.

What if the files have different numbers of pages?

Pages are alternated as far as possible, and the remaining pages are added at the end.

Can I mix more than two files?

Not yet. Mix two first, then merge or mix the result with another file.

Will quality change?

No. Pages are copied exactly as they were scanned.