Audio Splitter

Audiobook Chapter Splitter

Turn one long audiobook file into a clean set of chapter tracks. Drop your MP3 or M4A, find the chapter boundaries, adjust the split points, and export every chapter at once - no install, no command line, nothing uploaded.

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How to split an audiobook into chapters

  1. 01

    Open your audiobook

    MP3, M4A, AAC or FLAC. The file stays in your browser and is never uploaded.

  2. 02

    Mark each chapter

    Play through the book and drop a start/end marker pair at the beginning and end of every chapter. If you have a chapter list with timestamps, seek to each time and place the marker there.

  3. 03

    Check and adjust the split points

    Play each boundary and nudge it a fraction of a second either way, so no word gets clipped.

  4. 04

    Export every chapter

    Download all the tracks at once, numbered in order, or export a single chapter.

Split an audiobook MP3 into chapters in your browser

The usual advice for this job is to install Audacity or run an ffmpeg script. Neither is needed here: the file is opened in the tab, the chapter boundaries are marked on the waveform, and every chapter is exported in one pass. A 20-hour audiobook never leaves your computer.

Working from a chapter list or your ear

There is no automatic scan for spoken headings, and embedded chapter metadata is not read for you. If you already have the timestamps - a chapter list, a cue sheet, or the track times on the publisher's page - seek to each one and drop a marker there. Otherwise play the book and mark each chapter start and end as you hear it. Either way, every boundary lands where you decide.

M4B, MP3 and other audiobook files

M4B, MP3, M4A and WAV all open in the same editor, and a multi-hour book is not decoded as a whole, so the waveform appears quickly. The markers you place are the chapter boundaries: each start/end pair exports as its own file, numbered in order, one per chapter.

No upload: a 20-hour audiobook never leaves your computer

Server-based audiobook splitters make you upload the whole book first, which takes as long as the file is large and leaves a copy on someone else's machine. Here the audio is read locally and cut locally. That is also why there is no size ceiling worth worrying about: nothing is decoded as a whole, and the exported chapters keep the original bitrate.

Splitting audiobooks you own

This is a tool for files you already have the right to use - your own recordings, read-aloud material, or DRM-free audiobooks you bought. It only cuts a file you provide; it does not download, decrypt or distribute anything.

Supported formats

MP3 / AAC
Cut on frame boundaries - no re-encode
WAV
Cut by byte range - no re-encode
M4A / M4B
Cut on sample boundaries - no re-encode
FLAC / OGG
Decoded first; roughly 2 hours max in a browser tab

Questions

How do I split an audiobook into chapters?
Open the file, play it and place a start/end marker pair at every chapter boundary, adjust any that landed badly, then export every chapter in one pass.
Is there a free way to split an audiobook into chapters?
Yes. Splitting, unlimited clips and unlimited exports in the original format are free - no account, no watermark, no ads. Pro is a one-time $19.90 purchase that adds batch ZIP export, CUE / chapters export and re-encoding to MP3, AAC or Opus.
Can I split an M4B file with chapter markers?
Yes. An M4B splits like any other file here: place a marker pair at each chapter boundary and export. Embedded chapter metadata is not read automatically, so you mark the boundaries on the waveform.
How do I find the chapter boundaries?
Play through the book and drop a start/end marker pair wherever each chapter begins and ends. There is no automatic chapter detection, so you place every boundary yourself - which is also why a marker only ever lands where you chose.
Do I need Audacity or ffmpeg?
No. Nothing is installed and there is no command line: the whole job happens in the browser tab.
Will a 20-hour audiobook work?
Yes. Nothing is uploaded and nothing is decoded as a whole, so the file opens quickly and the chapters export without a size ceiling.
Can I split an audiobook on a Mac or a phone?
The same page runs on macOS, Windows, Linux, Android and iOS. For placing dozens of chapter markers, a larger screen is easier.
Can I export the chapter list as well?
Yes - as a CUE sheet or a Podcasting 2.0 chapters file, so your player shows the chapter list too. That export is part of Pro; splitting the audio stays free.

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