pdftk – Merge two PDF files containing even and odd pages of a book – Super User

A simple solution would be to use only pdftk in the following way:

pdftk A=even.pdf B=odd.pdf shuffle A Bend-1 output merged.pdf

PDFtk has a special feature that we added specifically to solve this problem of arranging scanned pages: shuffle. Say you have two PDFs: even.pdf and odd.pdf. Then you can collate them into a single document like this:

pdftk A=odd.pdf B=even.pdf shuffle A B output collated_pages.pdf

If your even pages are in reverse order, you can reverse its page range:

pdftk A=odd.pdf B=even.pdf shuffle A Bend-1 output collated_pages.pdf

The shuffle feature works by taking one page at a time from each of the input page ranges and assembling them into a new PDF. You specify these ranges after the shuffle keyword, and you can have more than two ranges.