Reviewed 2026-10-20 by the Spool editorial team · How we test
What an M4A file is
M4A is the audio-only version of the MP4 container. Inside is almost always AAC, a lossy codec that sounds better than MP3 at the same bitrate, or occasionally ALAC (Apple Lossless). You'll find M4A files in iTunes and Apple Music purchases, iPhone Voice Memos, GarageBand exports, WhatsApp voice notes forwarded from iPhone, and audio downloaded from YouTube in its original format.
M4A plays fine on iPhone, Mac, Android and Windows 10/11. Converting to MP3 is worth it when something only takes MP3: older car stereos and MP3 players, some DJ software, voice-over sites, podcast tools and upload forms.
Converting lossy to lossy: choose the bitrate carefully
Turning AAC into MP3 means decoding and re-encoding with a different lossy codec, so a little quality is always lost. To keep that loss inaudible, use an MP3 bitrate at or above the source's:
| Source | Typical M4A bitrate | Suggested MP3 |
|---|---|---|
| iTunes Store purchase (iTunes Plus) | 256 kbps AAC | 256–320 kbps |
| YouTube original audio | ≈ 128 kbps AAC | 192 kbps |
| GarageBand / Logic export | Your export setting | Match or exceed it |
| iPhone Voice Memos (Compressed) | Low-bitrate AAC, often mono | 96–128 kbps, Mono |
| Apple Lossless (ALAC) | Lossless | 320 kbps, or convert to FLAC to stay lossless |
The default is 192 kbps, encoded with LAME at a constant bitrate for maximum compatibility.
What carries over
- Text tags: title, artist, album, track number and similar tags are copied into ID3v2.3 tags, the version that older players read most reliably.
- Album artwork: embedded cover images are not carried over to the MP3. Re-add artwork in your music app (Get Info → Artwork) if you need it.
- Length and sample rate stay the same unless you change them.
Protected files can't be converted
Songs downloaded for offline listening in Apple Music, and Audible audiobooks, are encrypted with DRM and are tied to their apps. They often show an .m4p or .aax extension, or are simply unreadable outside the app. We don't remove DRM. iTunes Store purchases made since 2009 are DRM-free and convert normally.
Voice Memos from iPhone
In the Voice Memos app, tap a recording, tap ••• and choose Share → Save to Files. Then pick the M4A here from Files. Choose Mono and 96 kbps for speech: the MP3 is smaller than the original and works with any transcription service, email or podcast tool. Recordings set to Lossless (Settings → Voice Memos → Audio Quality) are larger ALAC files and benefit even more from conversion.
On a computer instead?
Apple Music on Mac and iTunes on Windows can also create MP3 versions: set the import encoder to MP3 in the app's file-import settings, then use File → Convert → Create MP3 Version. That's handy for whole libraries; this page is quicker for a handful of files, and works on any phone.
Troubleshooting
| Problem | Fix |
|---|---|
| "We couldn't read this file" | It's probably DRM-protected (Apple Music, Audible), or not really an M4A. |
| Cover art missing | Artwork isn't copied; add it again in your music app. |
| MP3 sounds worse than the M4A | Raise the bitrate to 256–320 kbps, or keep M4A if your device supports it. |
| Need it as a ringtone | Use the ringtone maker directly; it accepts M4A. |