Free online M4B to AIFF converter

M4B is an audiobook-oriented audio format based on the MPEG-4 container, usually carrying AAC audio and often supporting chapter markers, bookmarks, and metadata. AIFF is an uncompressed audio format developed by Apple, widely used for high-quality editing, archiving, and professional audio workflows.

Why convert m4b to aiff

Converting M4B to AIFF is useful when you need an uncompressed file for audio editing, mastering, restoration, or compatibility with software that works best with PCM audio. Since AIFF stores audio without lossy compression, it is a better choice for production tasks than audiobook-focused M4B files.

Best software for conversion

The best all-around choice is FFmpeg, because it is fast, reliable, free, and supports both formats. For a graphical option, Audacity is a good choice if you want to inspect or edit the audio before exporting. If you prefer a simple desktop converter, VLC and several dedicated audio converters can also handle this task.

How to convert with ffmpeg

Use FFmpeg when you want the most direct and accurate conversion. A typical command is:

ffmpeg -i input.m4b output.aiff

This converts the audiobook audio stream into AIFF. If the source contains chapters or metadata, note that AIFF support for audiobook-style chapter structure is limited compared with M4B.

How to convert with audacity

Audacity is useful if you want to edit the audio before saving it as AIFF. Open the M4B file, make any changes you need, then choose File → Export → Export as AIFF. This is a practical option for trimming, cleaning, or splitting audio before export.

Important things to know

• AIFF is uncompressed, so the output file will usually be much larger than the M4B source.
• Audio quality will not improve beyond the original M4B source; conversion only changes the container and compression type.
• Chapter markers and audiobook metadata may not carry over fully into AIFF.
• FFmpeg is best for batch conversion and automation.
• Audacity is best when editing is needed before export.

Recommended workflow

If you only need a clean conversion, use FFmpeg. If you need to edit the audiobook first, use Audacity. For most users, the simplest path is to open the M4B file in a converter, choose AIFF as the output format, and export with default PCM settings.

Summary

M4B to AIFF conversion is ideal when you need an uncompressed audio file for editing or professional use. FFmpeg is the best converter for speed and reliability, while Audacity is the best choice for hands-on editing before export.