PDF Booklet Maker rearranges the pages of a normal PDF so it can be printed on both sides of A4 or Letter paper, folded in half and stapled into a small book. You answer three questions, what paper you print on, how your printer handles two-sided printing and how you will bind the result, and the tool returns a print-ready imposed PDF with two pages on each side of every sheet. An A4 sheet folds into an A5 booklet (148 x 210 mm) and a US Letter sheet folds into a half letter booklet (5.5 x 8.5 in). The page order is the part that confuses people. In an 8-page booklet the first sheet carries pages 8 and 1 on the front and pages 2 and 7 on the back, and the second sheet carries 6 and 3, then 4 and 5. Printing the PDF in its normal order and folding it does not give a book. This tool works the order out for any page count and shows a sheet by sheet map before you print, so you can check where every page lands. Every sheet holds four pages, so the page count of a booklet is always a multiple of four. A 13-page PDF needs 16 page spaces on 4 sheets, and the tool adds the 3 blank pages at the end, or before the last page when that page is a back cover. Most print dialogs, including the Booklet option in Adobe Acrobat Reader, also expect you to know printer terms such as signatures, creep and binding edge. Here the choices are written in plain words, and the file is built in your browser, so a church program, school handout or zine never leaves your computer. To fix mixed page sizes before printing, use Make All PDF Pages Same Size first, and to join several files into one booklet, combine them with PDF Merger.
Printers call this job imposition: placing the pages of a document on large sheets so they read in order once the sheets are folded and bound. The simplest kind, used for almost every small booklet, is saddle stitch. All sheets are stacked, folded once down the middle and stapled through the fold, the way most magazines, wedding programs, church bulletins and zines are made. Because each sheet is folded once, it carries two pages on the front and two on the back, and the total is always a multiple of four: 4, 8, 12, 16 and so on. The page order follows a simple rule. With P pages, sheet 1 holds the last page and page 1 on the front, and page 2 and page P minus 1 on the back. Each next sheet moves one step toward the middle, so the innermost sheet carries the two center spreads. The tool calculates this for any length and draws the map, so you can compare it with your printout before printing the whole run. A few printer settings decide whether the result works. Set the scale to Actual size or 100 percent, because Fit to page shrinks the sheet again and shifts the fold away from the center. Two-sided printing must flip on the short edge for a landscape sheet, otherwise every back comes out upside down, which is why the tool can turn the backs in advance for printers that only flip on the long edge. Paper size in the print dialog must match the paper you chose in the tool. Thick booklets have one more problem called creep. The inner sheets of a folded stack stick out further than the outer ones, so text near the outside edge of the middle pages can be trimmed or end up closer to the edge. Keeping a single stapled booklet under about 15 sheets avoids most of it. Longer documents are better printed as several small booklets, called signatures, that are folded separately and then sewn or glued along the spine, which is how bound books are made. If the source pages are scans with two pages per image, split them first with Split Two-Page Book Scan, and if some pages are sideways, fix them with PDF Rotate.