Audio conversion
Convert FLAC to M4B
FLAC is a lossless format that stores every bit of a recording, while M4B is the audiobook format that phones and audiobook apps use for chapters, bookmarks, and remembered playback position. To convert, open the FLAC file in a converter and export it as M4B. Doing this on your own computer keeps the recording off other people's servers.
All 2,748 conversions verified on macOS, Windows, and Linux against the shipping release, this one included. Every conversion runs entirely on your own computer.
- Extension
- .flac
- Type
- Audio
- Typically
- Lossless music
- Extension
- .m4b
- Type
- Audio
- Typically
- Audiobooks, podcasts
- Compression
- Lossy
Convert FLAC to M4B on your own computer. Nothing uploads.
One-time purchase, no subscription. 14 days to change your mind.
How to convert FLAC to M4B
- Open Morphjet and drag in the FLAC file, or a whole folder of chapter files, that you want to convert.
- Choose M4B as the output format.
- Convert. The M4B is written next to your original, and nothing leaves your machine.
FLAC vs M4B: what actually changes
| FLAC | M4B | |
|---|---|---|
| File size | Larger, stores the full uncompressed detail | Much smaller, compressed for spoken-word listening |
| Quality | Lossless, identical to the source recording | Lossy, compressed to save space |
| Chapters and bookmarks | No built-in support | Yes, apps can jump between chapters and remember your spot |
| Compatibility | Needs a player that supports lossless audio | Opens in phone and tablet audiobook apps by default |
| Best for | Music and recordings you want to preserve exactly | Audiobooks and podcasts you want to listen through |
| Metadata | Tags for title, artist, album | Tags plus chapter markers and cover art |
When to convert, and when not to
Convert FLAC to M4B when you have a spoken-word recording, like an audiobook or a long podcast, and want to listen to it with chapter navigation and a remembered playback position on your phone.
Keep the FLAC original if it's music or anything you care about hearing at full fidelity, since M4B compresses the audio and that lost detail doesn't come back.
Why not just use an online converter?
Audiobooks and personal recordings aren't the kind of thing you want sitting on a stranger's server just to change formats. Converting FLAC to M4B through an online tool means uploading the whole file and waiting for it to come back down. Doing it on your own computer means the recording never leaves your machine.
Questions
Does converting FLAC to M4B lose quality?
Yes. FLAC is lossless and M4B is a compressed, lossy format, so there's a real quality drop. For spoken-word audio like audiobooks it's generally not noticeable, but for music it can be.
Will the M4B have chapters?
Only if they're set during conversion or already present as separate chapter files. A converter can combine multiple FLAC tracks into a single M4B and mark each one as a chapter.
Can I convert a whole folder of FLAC chapter files at once?
Yes. Most converters, including Morphjet, let you drag in a folder of FLAC files and combine or convert them together instead of one at a time.
Is M4B the same as MP3?
No. M4B is built specifically for audiobooks and podcasts, with support for chapters and remembered playback position that MP3 doesn't have.
Can I do this without uploading my file?
Yes. A desktop app like Morphjet converts on your own computer, so the file never travels over the internet. Your wifi doesn't even need to be on.
Morphjet runs this conversion and 2,747 others, all on your machine. Available now.
One-time purchase, no subscription. 14 days to change your mind.