Automatically split a PDF at each bookmark/chapter
WhiskFile Split PDF by Bookmarks is a free online tool to automatically split a PDF at each bookmark/chapter. Files are processed entirely in your browser — nothing is uploaded to any server.
Quick Answer
Automatically split a PDF at each bookmark/chapter. WhiskFile's Split PDF by Bookmarks is free, works in your browser, and requires no account. Your files never leave your device — all processing happens locally.
Upload your PDF
Upload a PDF that contains bookmarks or a document outline. Your file stays in your browser — nothing is uploaded to any server.
Select chapters
Use the level dropdown to split at Level 1, 2, or all levels. Or switch to Custom mode and use the interactive checkbox tree to hand-pick individual bookmarks.
Preview & download
Review the live output preview showing planned files with page ranges. Download individual chapters or all files as a single ZIP archive.
Max file size: 50 MB (free) · 500 MB (paid). Processing time: ~8s on average. Upload one file at a time.
Split PDF by Bookmarks runs entirely in your browser — no software to install. Works on any device with a modern browser.
Windows & Mac
Chrome, Firefox, Edge, Safari
iPhone & Android
Safari, Chrome mobile
iPad & Tablets
Full touch support
Unlike server-based tools that upload your documents, WhiskFile processes everything locally in your browser. Your files never leave your device — not even temporarily.
No upload required
Files are processed in your browser — nothing is sent to any server
100% private
No server storage, no data collection, no third-party access
Works offline
Once loaded, works without an internet connection
“I merge dozens of reports weekly. WhiskFile handles it instantly — no software to install, no sign-up hassle.”
Sarah Chen
Project Manager
“Splitting contracts by section used to take ages. Now I drag, drop, and it's done in seconds.”
David Kim
Legal Assistant
Help us improve by sharing your experience with Split PDF by Bookmarks.
Client-side processing
This tool now runs entirely in your browser — files never leave your device.
Result preview & sharing
Preview your processed file before downloading, and share results via a secure link.
The tool shows a clear message explaining that no bookmarks were found. PDF bookmarks are a navigation structure separate from a visible table-of-contents page — not all PDFs have them. Use our regular Split PDF tool to split by page ranges instead.
Each file is automatically named after its bookmark title (sanitized for safe filenames), with a numbered prefix for ordering (e.g. 01_Chapter_One.pdf, 02_Chapter_Two.pdf). Page ranges are included for clarity.
Yes. Use the level dropdown to split at Level 0 (top-level bookmarks only). You can also choose Level 1, 2, or All Levels for different depths. For fine-grained control, switch to Custom mode and hand-pick individual bookmarks.
Yes. Switch to Custom mode and use the interactive checkbox tree to select exactly which bookmarks you want to split on. Check Chapter 1, uncheck Chapter 2, check Chapter 3 — only selected bookmarks generate output files. This level of per-bookmark control is rare in free online tools.
Yes. The right panel shows all planned output files with their bookmark titles and page ranges before you click Split. Adjust your selection and watch the preview update in real time. The live preview updates as you adjust your selection.
When splitting into multiple files, click the ZIP button to download all chapter files in a single archive. Files are named by bookmark title. You can also download individual chapters one by one.
Yes, if the PDF has a proper bookmark/outline structure (not just a visual table-of-contents page). The tool reads the PDF's outline metadata to determine chapter boundaries. Most professionally created PDFs, ebooks, and reports have this structure.
No. The Split by Bookmarks tool runs entirely in your browser using pdfjs-dist and pdf-lib. Your files are never uploaded to any server — processing happens on your device. This is unlike Sejda, DeftPDF, and i2PDF which all upload files to their servers.
The dropdown lets you choose which depth of bookmarks to split on. Level 0 splits at top-level bookmarks only (e.g. Part I, Part II). Level 1 splits at the next level down (e.g. Chapter 1, Chapter 2). All Levels splits at every bookmark in the hierarchy. Custom mode lets you pick individual bookmarks.
No. Unlike Sejda (50 pages, 50MB, 3 tasks/hour) and DeftPDF (50MB), WhiskFile has no page count, file size, or task limits. Since processing happens in your browser, the only limit is your device's memory.
No. WhiskFile requires no account, no signup, and no registration. Just open the tool, upload your bookmarked PDF, select chapters, and download. No watermarks are added.
WhiskFile offers an interactive checkbox tree for per-bookmark selection and a live output preview — features rarely found in free online tools. Sejda only offers a level dropdown (no per-bookmark control) and limits free users to 50 pages/3 tasks per hour. PDFsam is desktop-only (no online version). WhiskFile processes files entirely in your browser with no limits.
Yes. WhiskFile is a free browser-based alternative to Adobe Acrobat for splitting PDFs by bookmarks. It offers an interactive bookmark tree, level dropdown, custom selection, live preview, and ZIP download — all without installing software or paying for a subscription.
Yes. Split PDF by Bookmarks on WhiskFile is completely free with no account required. Free users get 7 tasks per day with files up to 50 MB. There are no watermarks on any plan. Pro plans ($4.99/month) unlock unlimited tasks, 500 MB files, batch processing, and API access.
Yes. Split PDF by Bookmarks runs entirely in your browser using WebAssembly. Your files are never uploaded to any server — they stay on your device throughout the entire process. No data is transmitted, stored, or accessible to WhiskFile or any third party.
Yes. Split PDF by Bookmarks works on any device with a modern browser — iPhone, Android, iPad, tablets, Chromebooks, and desktop computers. No app download required. The interface adapts to your screen size automatically.
Split PDF by Bookmarks accepts PDF files as input and produces PDF output. The maximum file size is 50 MB on the free plan (500 MB for Pro users). There are no page count limits.
See how WhiskFile compares to other PDF tools on features, pricing, and privacy.
Chromebook & Linux
Any modern browser
