Split by Bookmarks
Split at any bookmark level — parts, chapters or sections — and name files after them.
Split by Bookmarks divides a PDF at its own outline — chapters, sections, any level you choose — so each part is named after its bookmark and starts where the author intended. It reads the outline on your device and enables Split once the outline is loaded.
Split by Bookmarks reads the outline built into your PDF and splits the file at each bookmark, naming every output after its section. If the PDF has no bookmarks you can enter page ranges by hand instead. It reads the whole outline tree, so you can split a book by Part, by Chapter or by Section — each level shows how many files it will produce. Split by Bookmarks is one of UnboundPDF's 53 free browser-based PDF and image tools: it runs on your own device with no upload, no account and no watermark, and reports what it measured on the output.
How to split by bookmarks — steps & common uses
What people use Split by Bookmarks for
Readers of long, bookmarked PDFs who want each section — chapter, tab or heading — saved as its own file.
- Split a manual into chapters
- Separate a report by section
- Break a book at its bookmarks
- Export each tabbed section
How to split by bookmarks
- Add a PDF; it is parsed in your browser and never leaves your device.
- The tool reads the whole outline and lists each section with its page range; pick a level, then untick any section you do not want.
- If the PDF has no bookmarks, type page ranges manually instead, one range per line.
- Click Split PDF and download a ZIP with one file per section.
Good to know: Reads the whole outline tree — pick a level, or check and uncheck individual bookmarks.
Questions about Split by Bookmarks 7
Are my files uploaded to a server?
No. UnboundPDF processes PDFs locally in the browser — documents are not uploaded to a server. We have no backend that receives, stores, or scans your files.
Which bookmarks are used to split?
Whichever outline level you pick defines the section breaks — level 1, level 2, level 3, or every level at once — and each section runs from its bookmark's page up to the page before the next one. Individual bookmarks can be checked or unchecked to override the level.
What happens if my PDF has no bookmarks?
The tool detects that and switches to a manual mode where you type the page ranges yourself, one range per line.
Which bookmarks does it split on?
It uses the outline to mark where each section begins, at whichever level you choose, then splits the pages between them. Nested bookmarks inside a section travel with it as that file's own outline.
What if my PDF has no bookmarks?
Then there is nothing to split on. Use Split PDF to choose page ranges instead.
Are the section files kept together?
Yes. Each part is grouped by its bookmark range and delivered together, so you can rename or file them afterwards.
Can I split a book into one file per chapter?
Yes — pick the chapter level in the level selector; each option shows the real number of files it will produce, and pages before the first bookmark come out as a named “Front matter” file rather than disappearing.
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How your files are handled
The work runs on your own device, inside the browser tab — so there is no server to send your document to.
- Nothing is uploaded. We have no backend that receives or stores documents, so we cannot see your files during processing or after.
- Your device does the work. Large documents are handled in stages, pages are rendered as you reach them, and each job is checked against your device before it starts — so a long run takes longer on a phone than on a laptop, nothing is queued behind other people's jobs, and you can stop a run at any point without touching your original file.
- No account and no watermark. The output is a clean file you can use anywhere, with no sign-up and no hourly cap.
More organize tools
Other free PDF utilities that work the same way — in your browser, no sign-up.