Oh, Poop!
You're probably looking at a preview of this file. This app can't run here. You need to figure out how to load this into a web browser. If you have the internet - You can use this copy.
1 page becomes 2 pages for front and back printing of graph papers.
Keep a selection of pages.
Smush several files into 1 file.
ummm... rotate.
Takes a long PDF, scales and rotates the pages then reorders them so you can print out a duplexed stack. Fold them and get a booklet out of it!
Assembling the PDFs you make elsewhere on this site - calendars, graph paper, mazes. It reads ordinary PDFs happily. It will not open fancy PDF files.
Pages are laid out two to a sheet in the order that makes a folded stack read correctly: the first and last pages share the outermost sheet, and the middle spread ends up in the center. Print double sided, flip on the short edge, fold, staple.
NO! Honestly, PDF is a terrible file format. That text you see? It probably isn't text. Fonts are a disaster. It doesn't really do unicode, but you can stick a 3d model in them for some reason. Plus the multi-layer password scheme. I'm not touching that. No one should.
Download your own copy of this utility. Works with no server required.
Keep a run of pages and throw the rest away.
Stack several PDFs into one, in the order you add them.
Turn every page a quarter, a half, or three quarters.
Page one, twice, so one double sided print comes out the same on both sides.
Two up and folded, in the order that makes a stapled booklet read correctly.