Merge Alternate PDF Pages
Interleave two PDFs page by page to rebuild a double-sided scan from separate front and back files, with an optional reverse. Free and fully private.
1. Front sides (odd pages)
2. Back sides (even pages)
What is the Merge Alternate PDF Pages?
The ByteTools Alternate Page Merger fixes the classic single-sided scanner problem. Scan all the fronts, flip the stack, scan all the backs, then drop both files in here — the tool interleaves them so the finished PDF reads 1, 2, 3, 4 in the right order.
- Interleaves two PDFs one page at a time
- Optional reverse of the second file for flipped stacks
- Handles files with different page counts gracefully
- Lossless — pages are copied without re-compression
- Page-count summary before you merge
- 100% local processing, nothing is uploaded
How to use the Merge Alternate PDF Pages
- 1
Drop the PDF containing the front sides (odd pages) into the first box.
- 2
Drop the PDF containing the back sides (even pages) into the second box.
- 3
Leave "reverse order" ticked if the back sides were scanned from a flipped stack.
- 4
Check the page counts, then click Merge Alternate Pages and download the result.
About the Merge Alternate PDF Pages
The ByteTools Alternate Page Merger fixes the classic single-sided scanner problem. Scan all the fronts, flip the stack, scan all the backs, then drop both files in here — the tool interleaves them so the finished PDF reads 1, 2, 3, 4 in the right order.
Because a flipped stack is scanned back to front, the second file is usually in reverse. That option is switched on by default, so the last page of the back-sides file lines up with the first front page exactly as it does on paper.
Both documents are merged locally in your browser and neither one is uploaded. Contracts, land records, ID documents and archive material can be reassembled without ever exposing them to a server, and the pages are copied without re-compression so your scans keep their original resolution.
Frequently asked questions
How do I combine front and back scans into one PDF?
Scan every front side into one file and every back side into another, drop both into this tool, and click Merge Alternate Pages. The pages are woven together so the finished document reads in the correct 1, 2, 3, 4 order.
Why is the reverse-order option switched on by default?
When you flip a stack of paper to scan the reverse sides, the last sheet ends up on top — so the back-sides file comes out backwards. Reversing it puts each back page next to its own front page. Untick it if your scanner already handled that.
What happens if the two files have different page counts?
The tool interleaves as far as it can, then appends whatever is left over at the end in its original order. It also warns you about the mismatch, which usually means a sheet was missed or double-fed during scanning.
Does interleaving pages reduce quality?
No. Pages are copied from both source documents at the object level with no re-compression, so scans keep their exact resolution and any text layers stay selectable.
Can I use this to merge two documents alternately for another reason?
Yes. Nothing about it is scanner-specific — any two PDFs can be woven together page by page. It is handy for pairing translations with originals, or interleaving a slide deck with its speaker notes.
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