Merge front and back scans
A single-sided scanner produces two files for a double-sided stack: one with all the fronts, then one with all the backs, usually scanned by flipping the whole stack, so the backs run from the last page to the first. This preset interleaves the two files, taking a page from each in turn (front 1, back 1, front 2, back 2…), and reverses the second file first so the backs line up with their fronts. The result is the document in reading order.
Options
Each row has a Pages field: leave it empty for the whole file, or type the pages to take, like 1-3, 5.
Both files are read locally in your browser and never uploaded. Bookmarks, links and form fields of the sources are kept.
Tips
- Drop the fronts first, then the backs; the order of the two rows is the order of the interleave.
- If your scanner feeds the backs in the normal order, untick "Second file runs backwards".
- A missing back leaves the two stacks out of step: add a blank page to the backs file with Organize PDF first.
Why it is private
Everything you type or drop here is handled by your browser, on your device. Nothing is uploaded. To verify, open your browser's developer tools, go to the Network tab, and use the tool: you will see no request carrying your data.
Frequently asked questions
- What if the two files have different page counts?
- Pages alternate while both files have pages left; the longer file's remaining pages follow at the end.
- Can I interleave more than two files?
- Yes: the tool takes one page from each file in turn, file after file. Reversal applies to the second file only.