Alternate & Mix
Interleave the pages of two PDFs — odd pages from one, even from the other — for scanned duplex stacks. Free, no upload.
Select two PDF files
first file = odd pages, second file = even pages — files never leave your device
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Interleave two PDFs into one
Scanned the fronts into one file and the backs into another? Alternate-mix weaves them into reading order — with a reverse option for duplex-back stacks.
Private by design
Weaving duplex scans of receipts or patient charts back into order runs in your browser, keeping both source files on your device.
Frequently asked questions
When would I use this?
Scanning double-sided documents: scan the fronts into one PDF and the backs into another, then interleave them into the correct order.
What if the two PDFs have different page counts?
Pages alternate until one document runs out; remaining pages are appended in order.
More essential PDF tools — all free, no upload
Read the free PDF guides — step-by-step walkthroughs for this tool and more.