Booklet maker

The output is in saddle-stitch imposition order, not reading order, and that is exactly what makes the finished booklet work. When a stack of sheets is folded in half, the two halves of each sheet end up far apart in the final page sequence: the outermost sheet carries the last page and the first page on its front, and page 2 with the second-to-last page on its back. A 16-page document therefore comes out as 16, 1, 2, 15, 14, 3, 4, 13, 12, 5, 6, 11, 10, 7, 8, 9 across four physical sheets. The Imposition order preview lists this sheet by sheet, front and back, before you build anything. Open the result in a reader and it will look wrong; print, fold and staple it and it reads correctly.

Saddle stitching folds sheets in half and each sheet holds four booklet pages, so the total has to be a multiple of four, and the tool pads the count up for you. A 17-page document is padded to 20 by adding three blank pages at the end, and the Padding info panel reports the exact number of blanks along with the resulting sheet count. Those blanks land in imposition positions near the back of the booklet, so they read as end matter rather than interrupting your content. If you would rather control where the blanks fall — a blank inside back cover, for instance — add your own empty pages to the source PDF first and drop that in; the tool will then find a multiple of four already and pad nothing.

No, creep is not compensated, so for a thick booklet you need to allow for it yourself. Creep, also called push-out or binder's creep, is the effect where inner sheets in a folded stack push slightly further out at the fore edge than the outer ones, so after the stack is trimmed the inner pages lose a sliver of margin that the outer pages keep. Every page here is placed at the same offset on its sheet regardless of which sheet it is, which is fine for a thin booklet on ordinary office paper and increasingly visible as the page count and the paper thickness grow. The usual remedies are generous outer margins in the source document, splitting a long document into several thinner booklets, or trimming the fore edge after folding.

For the landscape side-fold sheets, start with double-sided printing set to flip on short edge, then fold the stack in half and staple along the spine. Printer drivers do not use duplex terminology consistently, so print one sheet and check that its back is upright before committing to the full run. Disable auto-rotate, fit-to-page and shrink-oversized-page options, which can move the fold line off centre.

Each booklet page ends up at roughly half a sheet: an A4 source on an A4 sheet gives A5 booklet pages, and a Letter source on Letter gives half-letter. The output sheet is your chosen size turned landscape and split into two cells, with the gutter running between and around them, and each source page is scaled proportionally to fit its own cell. Because the fit is worked out per page, a document that mixes portrait and landscape pages keeps every page's proportions instead of having one shape forced on all of them. Text that was already small in the source will be about half as tall in the booklet, so print one sheet as a test before committing to a long run. The gutter field, 0 to 50 mm, is the one control that trades margin for page size.

Booklet maker is available without sign-up and does not add a logo or credit line to the imposed sheets. It re-places source pages and adds blank padding cells when the page count requires them. The component builds the file with pdf-lib in the browser without posting the selected PDF to a processing endpoint; practical size is constrained by browser memory.