Bulk M4B to WMA Converter Online — Free HD Quality
Drag and drop your multiple M4B files into this 100% free online M4B to WMA converter (.m4b to .wma), and click the Convert button to bulk convert them to WMA format in HD quality. Use the quality slider to fine-tune your WMA output, then download your converted files one by one or as a single ZIP — no signup and no downloads needed, and your original M4B files are removed from our servers right after. Also see:Convert multiple AIF to WAV at once.
Drop your M4B files here to convert to WMA, or click to browse
Converts .m4b to WMA (.wma) in HD quality — bulk, free, no signup
Choose FilesM4B vs WMA — File Format Comparison
See how M4B and WMA compare across file extension, MIME type, compression, and feature support. Related:Convert multiple M4B to iPod Audio at once.
| Feature | M4B | WMA |
|---|---|---|
| File Extension | .m4b | .wma |
| MIME Type | audio/mp4 | audio/x-ms-wma |
| Compression Type | Lossy | Lossy |
| Metadata Support | Yes | Yes |
What Is M4B Format?
MPEG-4 Audiobook — AAC audio in an MP4 container with bookmarking support, the standard format for audiobooks on Apple Books, Audible exports, and iPhone podcasts.
- Compression: Lossy
- Tags & Metadata: Supported
What Is WMA Format?
Windows Media Audio — Microsoft's proprietary lossy audio codec bundled with Windows Media Player, commonly found in legacy Windows media libraries and early-2000s digital music stores.
- Compression: Lossy
- Tags & Metadata: Supported