Convert M4A to AAC
This free M4A to AAC converter changes your MPEG-4 Audio (.m4a) file into a Advanced Audio Coding (.aac) file, right in your browser. There is nothing to install, no account to create, and no limit on how many files you convert.
100% private. Your file is processed locally in your browser with WebAssembly — it is never uploaded to a server, stored, or seen by anyone.
The conversion runs on your own device using ffmpeg compiled to WebAssembly (ffmpeg.wasm), so your file is never uploaded to a server. AAC is best for streaming and mobile devices, which is the usual reason to convert from M4A.
Why convert M4A to AAC?
- M4A and AAC are similarly compatible, so you are mainly changing the container.
- At a sensible bitrate, AAC stays close in size to M4A while changing the codec.
- Pick AAC when you need a file made for streaming and mobile devices.
M4A vs AAC
| Property | M4A | AAC |
|---|---|---|
| Full name | MPEG-4 Audio | Advanced Audio Coding |
| Container | MPEG-4 | ADTS |
| Typical codec | AAC | AAC |
| Compatibility | Wide | Wide |
| Lossless | No | No |
| Best for | Apple Music and efficient playback | Streaming and mobile devices |
How to convert M4A to AAC
Add your M4A file
Drag and drop your .m4a file onto the upload area, or click to browse and pick it from your device.
Start the conversion
Click "Convert to AAC". Everything runs locally with ffmpeg compiled to WebAssembly (ffmpeg.wasm) - your file stays on your device.
Wait a few seconds
A progress bar shows the conversion. The first run is slightly slower while the engine loads, then it is cached.
Download your AAC file
When it finishes, download the .aac file straight to your device.
Frequently asked questions
Is this M4A to AAC converter free?
Are my files uploaded to a server?
Will I lose quality converting M4A to AAC?
Will the file get smaller or larger?
What is the difference between M4A and AAC?
How long does the conversion take?
Related conversions
Need more formats or options? Use the full Audio Converter.