Bulk M4R to M4B Converter Online — Free HD Quality
Drag and drop your multiple M4R files into this 100% free online M4R to M4B converter (.m4r to .m4b), and click the Convert button to bulk convert them to M4B format in HD quality. Use the quality slider to fine-tune your M4B output, then download your converted files one by one or as a single ZIP — no signup and no downloads needed, and your original M4R files are removed from our servers right after. Also see:Online MP3 to OGA converter tool.
Drop your M4R files here to convert to M4B, or click to browse
Converts .m4r to M4B (.m4b) in HD quality — bulk, free, no signup
Choose FilesM4R vs M4B — File Format Comparison
See how M4R and M4B compare across file extension, MIME type, compression, and feature support. Related:Bulk M4R to MP2 tool.
| Feature | M4R | M4B |
|---|---|---|
| File Extension | .m4r | .m4b |
| MIME Type | audio/mp4 | audio/mp4 |
| Compression Type | Lossy | Lossy |
| Metadata Support | Yes | Yes |
What Is M4R Format?
iPhone Ringtone — AAC audio in an MP4 container under 40 seconds, the format iTunes and iPhone use for custom ringtones; identical to M4A in encoding but recognised by iOS as a ringtone file.
- Compression: Lossy
- Tags & Metadata: Supported
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