Rearrange the pages of a PDF into a different sequence. You can type an explicit page order, or apply one of the prepared arrangements: reverse the whole document, interleave the two halves of a duplex scan, or reorder pages for booklet printing. The duplex mode is the one to reach for when a sheet-fed scanner has given you all the odd pages followed by all the even ones.
Use the duplex sort. It interleaves the first half of the document with the second so the pages return to reading order, which is exactly the pattern a single-sided sheet feeder produces when you scan one side and then the other.
That happens when the second pass is fed without re-stacking. Reverse the document first, or scan the second side in the opposite order, then apply the duplex sort.
A custom order only includes the pages you list, so leaving a page out of the sequence removes it. If removal is the main goal, Delete PDF Pages states the intent more clearly.
Files are uploaded over an encrypted connection and processed on CoonTool's own server, not in your browser. The working copy is deleted automatically once the job is done, and in any case within 24 hours. Nothing is stored permanently and no account is required.