Audio conversion
Convert WMA to M4B
WMA is Windows Media Audio, a format built for Windows that most Apple devices don't handle natively. M4B is the audiobook format iPhone and Mac expect, and it remembers your playback position. To convert, open the WMA file in a converter and export it as M4B, done on your own computer without uploading a long recording anywhere.
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
- .wma
- Type
- Audio
- Typically
- Windows audio
- Compression
- Lossy
- Extension
- .m4b
- Type
- Audio
- Typically
- Audiobooks, podcasts
- Compression
- Lossy
Convert WMA to M4B on your own computer. Nothing uploads.
One-time purchase, no subscription. 14 days to change your mind.
How to convert WMA to M4B
- Open Morphjet and drag in the WMA file, or a whole folder if you're converting an audiobook or sermon series in several parts.
- Choose M4B as the output format.
- Convert. The M4B file is written to your computer, and nothing leaves your machine.
WMA vs M4B: what actually changes
| WMA | M4B | |
|---|---|---|
| Works on iPhone and Mac | No, not natively supported on Apple devices | Yes, M4B is the audiobook format Apple devices expect |
| Remembers your place | No, playback position isn't tracked by the format | Yes, audiobook apps bookmark your position automatically |
| Chapters | Not supported | Supported by the format, so long recordings can be split into chapters |
| File size | Moderate, based on an older codec | Similar or a little smaller at the same quality |
| Quality | Lossy, quality already baked in | Lossy again, so there's a small generational loss |
When to convert, and when not to
Convert WMA to M4B when you want an old audiobook, sermon, or long recording to play on an iPhone or Mac and behave like a real audiobook, remembering where you paused.
Keep the WMA if you only ever play it on a Windows machine already, since converting means re-encoding lossy audio into another lossy format for no real benefit.
Why not just use an online converter?
Audiobooks and personal recordings can run for hours, and some are private, a sermon, a lecture, a family recording. Uploading a file like that to an online converter means a stranger's server holds a copy while it processes, and possibly after. Converting on your own computer keeps the recording where it already lives, and it works even with no internet connection.
Questions
Does converting WMA to M4B lose quality?
A little. WMA is already lossy, and M4B uses lossy compression too, so you're re-encoding audio that's already been compressed once. For spoken word audio at a reasonable bitrate, the difference is usually not noticeable.
Will the M4B remember where I stopped listening?
Yes, that's the main reason people use M4B. Audiobook players on iPhone and Mac treat M4B files as audiobooks and bookmark your position automatically, unlike a plain WMA or MP3 file.
Does converting add chapters to my audiobook?
Not by itself. WMA files usually don't store chapter markers, so a single converted file stays one continuous track. What changes is the format supports chapters and bookmarking, so if you start with separate WMA files per chapter, you can convert them into a set of chapters.
Will my title and author tags carry over?
Yes, basic tags like title and artist carry over from WMA to M4B. It's worth checking them after conversion, since audiobook apps use that information to sort your library.
Can I convert WMA to M4B without uploading it anywhere?
Yes. Morphjet converts the file on your own computer, so it never travels over the internet. You can do it with your wifi off.
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.