Split a PDF by Its Bookmarks
A report, a manual or a book already knows where its chapters start — that is what the outline in the sidebar is. Splitting it by typing page ranges means looking every one of them up first, and getting a part that starts on the last page of the previous chapter if you are one out. This reads the bookmarks and cuts there, naming each file after the bookmark it came from.
Drop a PDF here or click to select
The outline is read as soon as the file lands
How it works
- Drop the PDF. Its outline is read immediately and the plan appears above the options: every part, its title and its page range, before anything is written.
- Pick the level. Only the depths this document actually has are offered, each with a count — level 1 — 12 bookmarks, level 2 — 74 bookmarks. Level 1 gives you chapters; level 2 gives you sections.
- Choose how the files are named and what happens to the front matter.
- Split. Every part lands in one ZIP.
Where each part ends
A chapter runs from its own bookmark to the page before the next bookmark at the same level or higher — not to the next bookmark of any depth. That distinction is the whole tool: if a chapter ends at its first sub-heading, every part is one section long and the rest of the chapter is missing. The last part runs to the end of the document.
Two things get reported rather than guessed at. A bookmark whose destination does not resolve to a page — which happens in documents assembled from other documents — is ignored and counted, because a chapter with no start page cannot be cut. Two bookmarks pointing at the same page are folded into one part, because the alternative is an empty PDF.
The options that matter
- Pages before the first bookmark. A title page, a copyright page and a table
of contents usually sit before chapter one. They can become their own
front matterfile, ride along on the first chapter, or be dropped — the plan line tells you how many pages that is before you choose. - Keep the sub-bookmarks. On, each part gets its own outline containing the headings that fell inside it, with their page numbers shifted to the part. A 40-page chapter with eight sections is still navigable on its own. Off, the parts have no outline at all.
- File names. Numbered titles keep the reading order in any file manager,
which plain titles do not. Characters a filesystem will not accept are replaced, and if two
chapters share a title the second gets a
(2)rather than overwriting the first.
FAQ
My PDF has no bookmarks. What now?
Then there is nothing to split on, and the status line says so. Add an outline with the bookmark editor — it takes a list of Title :: page lines — and then split. Or cut by page in Split PDF, which shows thumbnails and lets you click where each new document starts.
Do the parts keep their form fields, links and images?
Pages are copied whole, so their content, images, annotations and links come across. Links that pointed at a page in a different part now point at nothing — that is unavoidable when a document becomes several. Document-level metadata is not copied; set it with Edit metadata if it matters.
Can I split several PDFs at once?
Not here — the level and the naming depend on the outline of the file in front of you, and applying one document's choices to another is how you end up with twelve files called part-3. Do them one at a time; each produces its own ZIP.
Is the file uploaded?
No. The outline is read and the parts are written in your browser; nothing leaves the machine. See the privacy policy.
What about an encrypted PDF?
A file that opens without a password will split. One that needs a password to open must be unlocked first — Unlock PDF does that when you know the password.
Related PDF tools
- PDF Booklet Maker — Saddle-stitch imposition for printing.
- Interleave Two PDFs — Interleave front and back scan passes.
- Remove Blank PDF Pages — Delete blank pages by ink coverage.
- Merge PDF — Stitch multiple PDFs into one document, bookmarks intact.
- Split PDF — Chop a PDF into single pages or ranges.
- Extract PDF Pages — Grab a subset of pages into a new file.