Free online WMA to M4B converter

WMA is Windows Media Audio, an audio format developed by Microsoft and commonly used for compressed music and voice recordings. M4B is an AAC-based audiobook format used by Apple and other players, often supporting chapters, bookmarks, and metadata for long-form listening.

Why convert wma to m4b

Converting WMA to M4B is useful when you want to turn a Windows audio file into an audiobook-friendly format. M4B is better suited for narrated content because it can store chapter markers and resume playback from the last position in compatible apps.

Best software for the conversion

The best all-around choice is FFmpeg because it is fast, reliable, and supports high-quality audio conversion. If you need a simpler interface, VLC media player and Audacity can also help, though they are less ideal for preserving audiobook features. For creating proper M4B files with chapters and metadata, dedicated audiobook tools such as Chapter and Verse or Audiobook Binder are excellent options on supported platforms.

How to convert wma to m4b

To convert with FFmpeg, you can re-encode the audio to AAC inside an M4B container. A typical command is:

ffmpeg -i input.wma -c:a aac -b:a 128k output.m4b

This creates an M4B file from the source WMA. If your audio is already compatible, you may also be able to copy the stream without re-encoding, but in most cases re-encoding to AAC is the safest choice for broad compatibility.

Conversion tips

• Use AAC audio for the best compatibility with M4B players.
• Add metadata such as title, author, and album for audiobook organization.
• Include chapters if the source contains multiple sections or tracks.
• Check playback support in your target app before finalizing the file.

Recommended settings

For spoken-word content, a bitrate of 96 kbps to 128 kbps is usually enough. If the source WMA file is low quality, converting it will not improve the original audio, so start with the best available source file.

Online converters

If you prefer a web-based solution, choose a trusted converter that supports WMA input and M4B output. However, online tools may not preserve chapters or detailed audiobook metadata, so desktop software is usually better for serious audiobook conversion.

Summary

WMA to M4B conversion is best handled with FFmpeg or a dedicated audiobook tool when you need chapters and metadata. For simple audio conversion, a standard converter is enough, but for audiobook use, choose software that supports AAC encoding and M4B tagging.