Impose a PDF for saddle stitching
Feed in a PDF in reading order and get back the sheets in the order a stapled-and-folded booklet needs. Sixteen pages become eight printed sides; thirty-two become sixteen.
Load a file to start.
No upload — everything runs in your browser
Three steps
Pick the PDF, choose the finished page size (A5, B5, Japanese bunko) and which edge the book is bound on, then build. Page counts that are not multiples of four get blanks appended: a fourteen-page document becomes sixteen and produces eight sides. Print duplex, stack the sheets, staple through the centre fold and fold.
Do not send imposed files to a commercial printer
Japanese doujinshi printers — and most Western short-run printers — want single pages in reading order and impose the file themselves. Sending a pre-imposed PDF gets it imposed twice. Use this output for home printing, for convenience-store copiers, or when the printer explicitly says pre-imposed files are accepted. Bleed, trim marks and paper thickness differ from printer to printer — always check the spec sheet of the shop you are submitting to.
When the backs come out upside down
A spread sheet is landscape, so a duplex unit that flips on the short edge turns every back side over. If the reverse of sheet one prints upside down, tick "rotate backs 180°" and rebuild. Test one sheet before committing a whole print run.
Vocabulary: gutter, fore edge, creep
The gutter is the bound edge, the fore edge is the open one. In a thick saddle-stitched booklet the inner pages push outwards as paper stacks up — this is creep — so the fore edge is trimmed after folding. Leave about 3mm of slack there if your booklet runs past forty pages.
Frequently asked questions
What happens if my page count is not a multiple of four?
Blanks are appended until it is. Eighteen pages become twenty, which imposes as five sheets. If you want the blanks somewhere other than the end, add them in the source PDF first.
Right-bound or left-bound?
Japanese novels and manga read right to left and are right-bound; English books are left-bound. Get it wrong and page one lands on the opposite side of the sheet, so check where page one sits in the output before printing everything.
Why does the output have half as many pages?
Each output page is one printed side carrying two book pages. Sixteen book pages make eight sides, which is four sheets printed on both faces.
Is my file uploaded anywhere?
No. Reading, reordering and writing the PDF all happen in your browser, so unreleased artwork never leaves your machine.