How to split a book PDF into chapters
If the book PDF has a bookmark outline (most e-books, manuals and scanned textbooks with a table of contents do), open it in UnboundPDF’s Split by Bookmarks, choose the chapter level, and download the ZIP: one file per chapter, named after the heading, with the cover and contents kept as a “Front matter” file. It runs in your browser; the book is not uploaded.
Updated 19 August 2026
UnboundPDF is a free suite of 43 PDF and image tools that run entirely in your browser — merge, split, compress, edit text, OCR in 126 languages, redact, sign, convert and archive to PDF/A. Your document is read and written by the page on your own device; there is no document-upload endpoint in the core tools, no account, no watermark and no daily cap. Every result can be checked — with the Network tab, or with the Document Passport the Workspace writes for a chain of steps.
Steps
- Open the book in your reader and check the bookmark panel. If chapters are listed there, the tool can use them.
- Open Split by Bookmarks and drop in the PDF. The outline tree appears.
- Choose the chapter level — usually Level 1 or 2 — not the deepest sub-heading level. The count beside it is the number of files.
- Leave “Front matter” ticked to keep cover, title page and contents as their own file; untick chapters you do not need.
- Split and download the ZIP.
Check the bookmarks first
The tool reads the PDF’s outline — the bookmark panel — not the printed table of contents. Open the book in any reader and look at the panel on the left. If the chapters are there, you are done checking. If the panel is empty, the book has no outline; skip to the last section.
Split by Bookmarks is the tool for this — it runs in your browser.
Pick the chapter level, not the deepest one
A textbook outline often goes Part → Chapter → Section → Sub-section. Cutting at Section level gives you dozens of small files; cutting at Chapter gives you one file per chapter with its sections kept inside as bookmarks. The level selector shows the real file count for each choice, after grouping headings that share a page.
Front matter
Cover, half-title, copyright, dedication, contents — the pages before the first bookmark. They are kept as a named “Front matter” file by default so nothing disappears; untick it if you only want the chapters. Every page of the book ends up in exactly one file unless you chose to drop some.
The download
A ZIP with one PDF per chapter, each named from its heading (numbered so they sort in order) and each carrying its own sub-outline, so “Chapter 7” still has its sections in the bookmark panel.
If the book has no bookmarks
Use Split PDF with page ranges taken from the printed contents — “1-18, 19-44, 45-80” — or split every page and regroup. To add an outline to a book that lacks one, that is a different job; the editor does not build outlines today.
Related
The fuller guide: split a PDF by its bookmarks or chapters. Reorder or drop pages first: Organize PDF. Put chapters back together: Merge PDF.
Frequently asked questions
How do I split an e-book PDF into chapters?
If it has bookmarks, open it in Split by Bookmarks, choose the chapter level, download the ZIP — one file per chapter, front matter kept. If it has none, split by page ranges with Split PDF.
Will each chapter file keep its own bookmarks?
Yes. The part of the outline that belongs to each chapter is carried into its file with page references rebuilt.
What happens to the cover and contents pages?
They are collected into a “Front matter” file by default. Untick it if you do not want them.
Is the book uploaded?
No. The split runs in your browser; the file never leaves your device.