How to remove blank pages from a scanned PDF automatically

Duplex scanners often capture the empty back of every sheet. Deleting those pages by hand is slow. Delete blank pages checks each page and removes the empty ones for you.

Steps

Add your PDF.
Choose What counts as blank? There are three options: Only perfectly empty pages (strict), Empty pages, ignore faint specks (normal, recommended) and Also near-empty pages (loose).
Download the cleaned PDF. A message tells you how many pages were removed.

Picking the right setting

A scanned “blank” page is rarely pure white: there is paper texture, shadow near the edge and the odd speck. The setting decides how much of that noise still counts as blank.

Start with normal.
If blank pages remain, switch to the loose option, which also removes pages holding only tiny footers or scanner noise.
If a page with a faint pencil note or a light stamp was removed, switch to strict, which only removes perfectly empty pages.

Tips

Run it, then glance through the result in Organize PDF to make sure nothing important disappeared.
Pages that look blank but contain a tiny page number or header can be treated either way; check those.
To delete pages you pick yourself, use Remove pages from PDF.

When it will not work

Very faint writing, light-grey watermarks or pages with only a small logo can be judged as blank. Keep your original file and compare the page counts before sending the cleaned one.