M4B to AIFF converter
A free M4B to AIFF converter for MPEG-4 Audiobook files. Browser-based pairs here usually run in this tab, with no file upload.
Drop your M4B files here
or browse your device · paste with Ctrl+V
Accepts .m4b files. You can queue several files; each is processed one after another on your own device.
Your files never leave this device — there is no upload and no server to delete them from.
- 01
Add your M4B files
Drop them onto the box above or click to browse. They are read straight from disk — nothing is sent anywhere.
- 02
Check the settings
AIFF is already selected. Open the gear icon on any row if you want to change quality, dimensions or codec before converting.
- 03
Download your AIFF
Press convert and wait for the row to finish. Convert several files and you can take them all as a single ZIP.
M4B
MPEG-4 AudiobookAn M4A that flags itself as an audiobook, so players remember your position and honour chapter markers. Audible titles land here once stripped of DRM.
- Developed by
- Apple
- Released
- 2003
- Extension
- .m4b
- MIME type
- audio/mp4
- Compression
- Lossy
AIFF
Audio Interchange File FormatApple's uncompressed PCM format, the Mac equivalent of WAV. Identical audio quality; the difference is byte order and metadata conventions.
- Developed by
- Apple
- Released
- 1988
- Extension
- .aiff, .aif, .aifc
- MIME type
- audio/aiff
- Compression
- Uncompressed
- M4B is lossy and AIFF is lossless. Re-saving cannot recover details removed by the lossy source. The output is usually larger with similar visible quality, not a repaired original.
Questions about converting M4B to AIFF
Is this M4B to AIFF converter free?
Yes. Converting M4B to AIFF here is free, with no account, no watermark and no daily quota. The work runs on your own device, so there is no server cost to pass on to you.
Is my M4B file uploaded anywhere?
For browser-based pairs, your file is read locally and converted by ffmpeg in this tab. No file payload is uploaded; you may still see analytics and engine downloads in network logs.
Is there a file-size limit for M4B to AIFF?
There is no imposed upload cap when it runs in-browser, but each conversion still depends on your device and browser memory. Large videos are the first practical limit, then memory-heavy documents or images.
Does converting M4B to AIFF lose quality?
Nothing is intentionally discarded in this step, because AIFF is lossless. A M4B file encoded with lossy settings stays lossy, so missing detail is not recovered.
Can I convert several M4B files to AIFF at once?
Yes. Drop in several files and each gets its own row; they are processed one after another on your device. You can download them one by one or as one ZIP.
Does M4B to AIFF work on a phone, Mac or Chromebook?
Most modern browsers on Windows, macOS, Linux, ChromeOS, Android and iOS work. Very large videos are often more reliable on desktop or a browser with more memory.
Why do some conversions take longer on first run?
The conversion engine has to download first. Small codec bundles are fast, while ffmpeg is commonly 12–30 MB; later conversions of similar type use the cached engine.
I converted a file and the output is blank or unusable. What should I check?
Start over with default settings, then change one option at a time (quality, bitrate, page size, or codec) to isolate what changed behavior. If it keeps failing, retry with a smaller file and confirm the source format matches the pair.
Convert other formats to AIFF
41 formats can become AIFF here.
Convert M4B to other formats
A M4B file can become any of these.
AIFF to M4B
The reverse conversion
MP4 to AIFF
MP3 to AIFF
WAV to AIFF
Extract Audio from Video
Pull the soundtrack out of a video as an MP3.…
Compress Audio
Lower the bitrate of audio files to save space.…
Trim Audio
Cut a section out of an audio file.…
Normalise Audio
Even out loudness across files so nothing is jarring…