Foldproof — PDF Booklet Maker

Good pages. In good order.

Foldproof turns an existing PDF into sheets for a small folded booklet. Choose A4 or US Letter, select the binding side, check the numbered page map, and download a PDF for duplex printing.

Desktop early release · version 0.1.0 · $9 one-time download. This purchase includes the current application, instructions and licenses. No subscription or promise of future updates.

Inside the download

• A local browser tool with a built-in eight-page sample.
• A4 or US Letter landscape output, with two source pages per printed side.
• Left- or right-side binding, adjustable safe margins and a scale summary.
• Automatic blank-page padding to complete a multiple of four.
• A labelled placement map and a separate duplex-calibration PDF.

The map is a schematic, not a preview of your PDF artwork. There is no integrated PDF-content viewer: download the result and open it separately in your PDF viewer.

Check your file before buying

This version accepts one static PDF, 1–128 pages, up to 25 MiB. Pages must be equally sized, portrait and unrotated. Encrypted PDFs, interactive forms, mixed page sizes and rotated pages are not supported. Comments, links and attachments are not carried into the print file.

Pages are fitted within each half-sheet: oversized artwork is reduced, small pages are not enlarged, and text does not reflow. Foldproof does not edit PDF content, prepare separate signatures, compensate for paper creep or certify print-shop requirements.

Designed for desktop use. Mobile use is not verified. Opening the downloaded HTML and downloading a PDF have been checked by the owner, but this is not a compatibility guarantee for every browser or PDF.

Make a test print first

Start with matching paper, landscape, actual size / 100%, double-sided printing and short-edge flip. Print one exported PDF page per side and turn off any extra booklet or multiple-pages mode. Use the calibration PDF, then inspect a folded test copy before printing more. Printer behavior varies; physical print compatibility is not guaranteed. The page limit does not mean every printer or stapler can handle 32 folded sheets.

Your file stays local

Foldproof processes the selected PDF in your browser and does not upload it to a server or AI service. Use author-owned PDFs and keep the original. You may use the application for your own personal or commercial work under the included license.

AI disclosure: AI tools assisted development of the code, written material and code-generated vector graphics. The booklet arrangement uses deterministic rules; no AI model processes your PDF.

Questions about the purchased files? Contact marekkourimsky@gmail.com. Please describe the issue and settings first rather than sending a confidential document.