Alternate & mix
Interleave pages from two files — handy for front and back scans.
- Zero-transmission processing
- No watermark
- Limited daily trial
- Unlimited on Pro
Drop your PDFs here
or pick them from your device
Your files are never transmitted. Nothing is uploaded.
Before you start
- Add the fronts first and the backs second — use the arrows to swap them if needed.
- Most duplex scans give the backs last page first: choose Reverse order for the second file.
Good to know
- Accepts
- Files at once
- Up to 2
- Transmission
- None — nothing is uploaded.
Chain it
Next, run Rotate PDF → OCR PDF on the result back to back — nothing to download in between.
How to do it
Add your file
Add two PDFs, the fronts and the backs — or one PDF with all the fronts followed by all the backs. This is the other half of rescuing a double-sided scan made on a single-sided scanner.
Set it up the way you want
Choose whether to reverse the second file. You almost always need to: flipping a paper stack reverses it, so the backs were scanned from the last page forward.
Download the result
Download the interleaved document. Front, back, front, back — the original order, rebuilt.
Questions about Alternate & mix
- How do I know whether to reverse?
- Look at the last page of your second file. If it is the back of page one, reverse it. That is what happens when you flip a stack over and feed it again, which is what nearly everyone does.
- The files have different page counts.
- It still works — the longer file simply continues after the shorter one runs out. That usually means one page failed to feed, so it is worth checking which side is short before relying on the result.
- Is there an easier way to do double-sided scanning?
- A duplex scanner, which does both sides in one pass. This tool exists because most people do not have one, and the two-pass method plus interleaving gets the same result from the scanner you already own.