How to use the M4B to MP3 converter
- Choose your M4B file or drop it on the box.
- Pick an audio quality. 192 kbps is the usual choice; 320 kbps for music you care about.
- Click "Convert to MP3". A progress meter shows how far along it is.
- Download your MP3 and listen to it right on the page.
Why convert M4B to MP3?
Many car stereos, MP3 players and apps cannot play M4B audiobooks. MP3 can, everywhere.
- M4B: not supported by many car stereos and MP3 players.
- MP3: plays on every device.
- MP3: small files.
For speech, 64–96 kbps MP3 keeps very long audiobooks small. Use the MP3 Splitter afterwards if the file is too long for your player.
M4B vs MP3
| M4B | MP3 | |
|---|---|---|
| Full name | MPEG-4 Audiobook | MPEG-1 Audio Layer III |
| Type | Audio | Audio |
| Created by | Apple (2003) | the Fraunhofer Institute and MPEG (1993) |
| Compression | Lossy | Lossy |
| Codec | AAC | MP3 |
| Best for | Audiobooks and long spoken-word recordings | Music, podcasts, audiobooks and ringtones |
| Plays on | Apple Books, iTunes, VLC and audiobook apps on Android | Every phone, computer, car stereo, smart speaker and browser |
Does converting M4B to MP3 lose quality?
Both formats are lossy, so converting adds a small amount of loss. Use the same or a higher bitrate than your M4B (192 kbps covers most files) and the change is inaudible.
How long does it take?
A few seconds for a song, and under a minute for an hour-long recording on most computers.
What is an M4B file?
M4B is an M4A file marked as an audiobook. Apple Books and many audiobook apps remember your listening position in M4B files and can show chapters. Audiobooks bought from stores such as Audible are copy-protected and cannot be converted.
What is an MP3 file?
MP3 is the most widely used audio format in the world. It removes sounds people are unlikely to hear, shrinking a song to about a tenth of its CD size. At 192 kbps or higher most listeners cannot tell it from the original, and every device plays it. Its patents expired in 2017, so it is now free to use.
Frequently asked questions
Is the M4B to MP3 converter free?
Yes, completely free, with no sign-up and no watermark. Files up to 1 GB each can be converted, and there is no daily limit.
Is my file uploaded to a server?
No. The converter runs inside your browser using WebAssembly, so your file is processed on your own device and never sent to us or anyone else.
Will the MP3 sound as good as the M4B?
Both formats are lossy, so converting adds a small amount of loss. Use the same or a higher bitrate than your M4B (192 kbps covers most files) and the change is inaudible.
Can I convert MP3 back to M4B?
Yes, use the M4B Converter and choose M4B as the output.
An audiobook (M4B) will not play in the car. What should I do?
Convert M4B to MP3, then split it into parts if it is very long.
Does it work on iPhone and Android?
Yes, in Safari, Chrome and other modern mobile browsers. Short files work best on phones; for long or high-resolution videos a computer is faster.