TL;DR: Upload a multi-page PDF and download a booklet-imposed copy ready for saddle-stitch printing (2-up, page-order corrected).
Rearrange PDF pages for booklet printing online for free. Automatically reorder pages so that when printed and folded, they create a correctly ordered booklet. No software needed.
Like the rest of the 179-tool PrivaTools suite, PDF Booklet is MIT-licensed and self-hostable. The public demo deletes your file as soon as the response leaves the server — verifiable in the open-source codebase on GitHub.
Saddle-stitch binding folds the sheets in half — the front cover of sheet 1 carries pages 8 and 1, the back carries pages 2 and 7. The math is fixed by binding geometry.
PrivaTools pads with blank pages at the end before computing the imposition order, so the booklet always works.
Saddle-stitch caps at about 80 pages (20 sheets) because the inner pages start to creep. For longer documents use perfect binding (no imposition needed).
See how PrivaTools compares to iLovePDF, Smallpdf, Adobe Acrobat, and other free PDF tools.