Bulk AIFF to M4B Converter Online — Free HD Quality
Drag and drop your multiple AIFF files into this 100% free online AIFF to M4B converter (.aiff 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 AIFF files are removed from our servers right after. Also see:Bulk WAV to OPUS tool.
Drop your AIFF files here to convert to M4B, or click to browse
Converts .aiff to M4B (.m4b) in HD quality — bulk, free, no signup
Choose FilesAIFF vs M4B — File Format Comparison
See how AIFF and M4B compare across file extension, MIME type, compression, and feature support. Related:Make AIFF files into MP2.
| Feature | AIFF | M4B |
|---|---|---|
| File Extension | .aiff | .m4b |
| MIME Type | audio/aiff | audio/mp4 |
| Compression Type | Lossless | Lossy |
| Metadata Support | Yes | Yes |
What Is AIFF Format?
Audio Interchange File Format — Apple's uncompressed audio standard functionally equivalent to WAV but preferred in professional Apple audio workflows and GarageBand projects.
- Compression: Lossless
- 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