WAV to M4B

Convert uncompressed WAV recordings into a chaptered M4B audiobook — right in your browser. Perfect for home narrators and self-published authors. Your files never leave your device.

New here? M4B is the audiobook format Apple Books, Plex, and most modern players recognise — chapters, cover art, and resume position in one tagged file. Drop your audio in and you'll get back a single M4B with chapters at every file boundary.

  • One chapter per file, titled from the filename
  • Optional cover art, embedded at 1200×1200
  • More detail on the FAQ page
Your files never leave your browser

Audiobook details

Title is required.

Author is required.

Verify metadata (optional)

Cover image (optional)

Square images work best. Non-square covers are padded to 1200×1200 with a white background and embedded as JPEG.

Output bitrate

96 kbps, 128 kbps, 192 kbps, 256 kbps

To enable: add at least one audio file, enter a title, enter an author.

How it works

  1. Step 1

    Drop your files

    Drag MP3, M4A, WAV, FLAC, OGG, or Opus files into the browser. They stay on your device.

  2. Step 2

    Add metadata

    Reorder chapters, set the title, author, narrator and cover. Embedded tags auto-fill what they can.

  3. Step 3

    Download M4B

    A single tagged, chaptered audiobook — ready for Apple Books, Plex, or any M4B-aware player.

WAV to M4B — common questions

Why are my WAV files so much larger than the output M4B?
WAV stores uncompressed PCM audio, which is very large. The M4B output uses AAC at 64 kbps — the standard for spoken-word audiobooks — which is roughly 15–20× smaller with no audible difference for speech. A 1 GB WAV audiobook typically becomes a 60–80 MB M4B.
I recorded my narration as WAV. Can I convert it directly to M4B?
Yes — this is a common use case for self-published authors and home narrators. Drop your WAV chapter files, fill in the title and author fields, optionally add a cover image, and click Convert. The tool will encode each chapter to AAC and join them into a single chaptered M4B.
Can I mix WAV with other formats like MP3?
Yes. Every input file is re-encoded to AAC before being joined, so you can mix WAV, MP3, FLAC, and other supported formats in the same audiobook without any extra steps.
Are my WAV files uploaded anywhere?
No. Conversion runs entirely inside your browser using a WebAssembly build of FFmpeg. Your audio files never leave your device. Open your browser's Network tab while converting to verify there are no upload requests.

Convert other formats to M4B