Splitting every page into its own file is easy. Splitting a 240-page document into its seven actual chapters is the job people usually have — a scanned book, a merged bundle of separate documents, a report where each section goes to a different person.
Split PDF has three modes, and custom page ranges is the one you want here. Type the ranges — 1-24, 25-71, 72-118 — and each becomes its own PDF. Every page is copied across exactly as it is, so nothing is re-rendered or downgraded, and several output files come back together as a ZIP. There’s no automatic chapter detection, and that’s a feature as much as a limitation: bookmarks in a scanned or merged document are usually absent or wrong, so you’d be checking them anyway, and reading the page numbers off once is faster and always correct.
Finding the boundaries is quick either way. If the document has a table of contents, it lists your ranges for you — with one caution: printed page numbers rarely match PDF page numbers, since front matter (cover, title, copyright, contents) is unnumbered or numbered in roman numerals, so find the offset once by looking up the PDF page of printed page 1 and adding that difference to every number in the contents. If it doesn’t, open it in any reader and use the thumbnail sidebar — chapter openings and document boundaries are visually obvious at thumbnail size, a mostly blank page with a big heading, or a change of paper colour where one scanned document ends and the next begins, and you just note the page numbers as you scroll. Overlaps and gaps are allowed, too — ranges don’t have to be contiguous or exclusive, so 1-10, 8-15 gives you two files that share pages 8–10, handy when a section boundary is genuinely ambiguous, and pages you don’t list simply aren’t output.
The other two modes beat ranges in specific cases. Extract every page — one PDF per page — is right when every page is a standalone item: forms that must be submitted individually, certificates, a batch of scanned receipts. Fixed chunks of N pages is right when the structure is regular: a double-sided scan of two-page invoices splits perfectly into chunks of 2, and a 200-page file that needs to go out as manageable email attachments splits into chunks of 20. Ranges are for everything with real structure.
A common case worth naming: feed a stack of paper through a document feeder and you get one PDF containing six unrelated things. Ranges separate them back out in a single pass — worth doing, because a file called scan0031.pdf containing your lease, your insurance, and two invoices is a file you’ll never find anything in again. While you’re there, set a sensible title on each piece so they’re searchable later.
A few things to check before and after: a password-protected file can’t be split, since an encrypted PDF can’t be read, so remove the password with Unlock PDF first. Pages out of order? Reorder them before splitting, so your ranges are contiguous. Only removing a few pages? Delete pages gives you back one trimmed file instead of several. Wrong pieces? Merge selected outputs back together in a different combination. And splitting because it’s too big to email? Compress it first — often that alone is enough.
Related reading: How to Split a PDF into Multiple Files and How to Split a PDF Into Files That Each Fit a Size Limit.
Split it with the free Split PDF tool — no sign-up required, no watermark, and the file is wiped the moment the download finishes.