Alternate & Mix PDFs
Interleave the pages of two PDFs — perfect for combining separately scanned front and back sides.
Add the fronts PDF first and the backs PDF second. Most feeders scan backs in reverse, so that option is on by default.
Add documents
PDF, DOCX, images, spreadsheets or text files.
Choose a tool
Interleave the pages of two PDFs — perfect for combining separately scanned front and back sides.
Fine-tune
Optional — sensible defaults are already set.
About Alternate & Mix PDFs
Alternate & Mix PDFs interleaves the pages of two PDFs: page 1 from the first file, page 1 from the second, then page 2 from each, and so on. It's made for double-sided paper on a scanner that only scans one side. Scan all the fronts, flip the stack, scan the backs, and this tool rebuilds the correct order.
When it helps
- Reassembling double-sided contracts or forms scanned with a single-sided document feeder
- Combining odd and even pages that were exported or printed separately
- Alternating question and answer pages from two matching files
Tips
- Add the fronts PDF first and the backs PDF second. Order matters.
- When you flip a stack to scan the backs, the feeder reads them last page first. That's why 'Second PDF is in reverse order' is on by default. Turn it off if your backs PDF is already in normal order.
- If the files have different page counts, the extra pages are added at the end and the summary tells you. That often means a page was double-fed or skipped.
Good to know
Quick answers about alternate & mix pdfs in your browser.
Add the front-side PDF first and the back-side PDF second, keep the reverse option on if you flipped the stack, and run the tool. The result alternates front, back, front, back.
No. It takes exactly two files. For other combinations, use Merge PDF and then Organize PDF.
Yes. There is no sign-up, no watermark and no limit on how many files you process.
No. Files are read and processed locally in your browser, so they never leave your device.
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Part of the More PDF Tools collection.