Free online OMA to AAC converter

Source format: OMA

OMA is a Sony audio container format most commonly associated with ATRAC audio used on some Sony devices and software. It was often used for protected music transfers and playback on older Sony hardware, including certain Walkman players and Sony media applications. In practice, OMA files may contain audio that is not directly playable in many modern apps without conversion.

Target format: AAC

AAC (Advanced Audio Coding) is a widely supported compressed audio format used by smartphones, media players, streaming services, and editing software. It offers good sound quality at relatively small file sizes, broad compatibility, and efficient compression, making it a common choice for music libraries and portable playback.

How to perform the conversion

The most reliable way to convert OMA to AAC is to use desktop audio software that can decode the OMA/ATRAC stream and then re-encode it to AAC. A practical option is FFmpeg, provided your OMA file is not protected by DRM and is supported by your build of FFmpeg.

1. Install FFmpeg on your computer.
2. Open a terminal or command prompt in the folder containing the OMA file.
3. Run a command such as ffmpeg -i input.oma -c:a aac -b:a 192k output.m4a.
4. If you specifically need an AAC audio file, you can also use output.aac as the filename, but .m4a is often preferred because it is a common container for AAC audio.
5. Play the result in a media player to confirm that the conversion succeeded.

If you prefer a graphical workflow, some audio editors and converters that support ATRAC/OMA decoding can import the file and export to AAC through File → Export or File → Save as. On 101convert.com, you can convert the file online for free without installing any software.

Notes on quality and limitations

OMA files may be protected, and DRM-protected files usually cannot be converted unless the protection is removed by authorized means. Also, because AAC is a lossy format, the conversion will not improve audio quality; it will only preserve as much quality as possible during re-encoding. For best results, choose a higher AAC bitrate such as 192 kbps or 256 kbps if file size is not the main concern. If the source OMA file is already low quality, the output will reflect those limitations.