How to scan double-sided documents with a single-sided scanner
Many office scanners and multifunction printers only scan one side. You do not need to feed each sheet twice: two passes and two minutes of work give you the complete document in order.
Step 1: two passes through the scanner
Put the stack in the feeder and scan it as a PDF: those are the fronts. Take the stack out, turn it over without shuffling it and scan it again: those are the backs, which come out from the last page to the first.
Step 2: interleave the pages
Open Interleave pages, put the fronts PDF on the left and the backs PDF on the right, and keep “The back sides are in reverse order” ticked. The result alternates front 1, back 1, front 2, back 2…
Step 3: remove the empty backs
Single-sided sheets leave blank backs. Remove blank pages finds them automatically — ignoring scanner specks and gray paper — and removes them after you check.
Step 4: make it light and searchable
Scans are heavy: compress the PDF to email it, and run OCR PDF so you can search its text.