Batch Images to PDF

This is the only tool in the family that takes images rather than PDFs, and the distinction worth understanding is one-to-one versus many-to-one. Here each image becomes its own separate single-page PDF, which is what you want when the images are unrelated — a folder of receipts, each needing to be filed as its own document. If instead you want one PDF containing all the images as sequential pages, that is the ordinary JPG to PDF tool. Mechanically, each image is embedded once as an XObject and drawn onto a page with a placement matrix; the pixels are carried across without re-compression, so a JPEG keeps its original encoding and loses nothing. The page size choice decides what the result is for. Fitting the page to the image gives a borderless document with no white margin, ideal for screenshots and photographs. Fitting to A4 or Letter with margins gives a document that prints properly on a real sheet, which is what a receipt intended for filing needs.