Split Two-Page Book Scan is a free browser tool that turns a PDF of book spreads into a PDF of single pages. When a book, manual, magazine or bound archive is scanned open on a flatbed or photographed with a phone, each image holds two facing pages side by side. The file reads awkwardly on a phone or e-reader, page numbers in the PDF do not match the page numbers printed in the book, and OCR software often reads straight across both columns. This tool fixes that in one pass. Upload the file and the first spread appears with a vertical cut line over it. Drag the line onto the spine, or fine-tune it with the slider or the arrow keys, and every spread in the document is cut at that position, so a 120 page scan becomes a 240 page PDF. Because scans are rarely perfectly aligned, the line can also be moved for a single page without changing the rest. The reading order setting decides which half comes first: left page first for English and other left-to-right languages, right page first for manga and books in Arabic, Hebrew, Persian or Japanese. Portrait pages, such as a front cover scanned on its own, are recognised and left whole, and the first and last page can be kept whole explicitly. The split is lossless. Instead of re-rendering images, the tool sets the visible area of each new page to one half of the original, so the scan keeps its full resolution, any text layer from OCR stays selectable, and the scanned image is stored once rather than twice. Everything runs locally with pdf.js and pdf-lib, so private archives and unpublished material never leave the device. This is different from PDF Splitter, which separates a document into several files by page range. To trim the dark scanner borders afterwards use PDF Crop & Resize, to straighten pages scanned upside down use PDF Rotate, and to make text searchable or copyable use PDF to Text.
Scanning a book two pages at a time is the fastest way to digitise it, which is why so many archive scans, library copies and phone-camera captures end up as spreads. The cost appears later. A spread is too wide to read comfortably on a phone or e-reader, so every page has to be zoomed and panned. PDF page numbers drift away from the printed page numbers, which makes citing and bookmarking confusing. OCR and text-to-speech tools often read a line straight across both pages instead of finishing the left page first. Printing a spread shrinks two pages onto one sheet. Cutting each spread at the spine solves all of these at once. A few practical notes help get a clean result. Place the line in the gutter, the shadow or white strip where the pages meet, rather than on the text; a small amount of the opposite page at the edge is harmless and can be trimmed later. If the book was scanned in two sessions, the spine is often in a different place in each half of the file, and moving the line for individual pages handles that without starting over. Scans saved upright with the spread turned sideways should be rotated first with PDF Rotate, so the spine runs from top to bottom before you split. After splitting, PDF Crop & Resize removes dark scanner edges, Make All PDF Pages Same Size evens out pages that came out at slightly different widths, and PDF Page Count Checker confirms the final page count matches the book.