Free online AT3 to OMA converter

What the AT3 format is

AT3 is an audio file extension commonly used for Sony ATRAC3-compressed sound, including music, voice recordings, and game audio. Files may contain ATRAC3 data as a standalone stream, and some Sony applications use the extension for audio extracted from ATRAC-based media. You can encounter AT3 files from Sony devices, PlayStation-related software, older portable music players, and legacy audio libraries.

AT3 identifies the filename extension, not every property of the stream. The file may use different ATRAC3 settings, and some files may include headers or application-specific data that affect compatibility.

What the OMA format is

OMA is Sony’s OpenMG audio container, usually associated with ATRAC3 or ATRAC3plus audio. It can store codec parameters, track metadata, and, in older OpenMG libraries, digital-rights-management information. Sony SonicStage and compatible legacy hardware commonly use OMA files.

OMA is useful when a Sony application expects the OpenMG container instead of a bare ATRAC3 stream. It is not a broadly supported replacement for MP3, AAC, or WAV; many current media players cannot open it, especially when the file is encrypted.

How to convert AT3 to OMA

The simplest option is the built-in converter on 101convert.com, which can be used free without installing software:

1. Open the AT3-to-OMA conversion page on 101convert.com.
2. Select the source file with the .at3 extension.
3. Choose OMA as the output format and start the conversion.
4. Download the resulting .oma file and test it in the intended Sony application or device.

For a protected AT3 or an AT3 tied to an OpenMG library, use the Sony software that created or manages the library, such as SonicStage. Import the track through File → Import, then use the application’s device-transfer or conversion command to create an authorized ATRAC/OpenMG copy. Menu names vary by SonicStage version; a normal file converter cannot remove OpenMG encryption.

FFmpeg is useful as a diagnostic or intermediate conversion tool when the AT3 is an unprotected ATRAC3 stream:

ffmpeg -i input.at3 -c:a pcm_s16le intermediate.wav

Standard FFmpeg builds generally read ATRAC3 but do not provide a reliable OMA muxing workflow. The WAV output can be imported into Sony software that supports OpenMG/ATRAC encoding, but this creates a new lossy encode and does not restore DRM metadata.

Quality and compatibility limitations

ATRAC3 is already lossy. Converting AT3 to OMA without changing the codec can preserve the encoded audio, while decoding to WAV and re-encoding to ATRAC introduces another generation of lossy compression. Keep the original AT3 file as a backup.

OMA files can be encrypted or restricted to the OpenMG account and device that created them. A successfully produced .oma file may still fail on modern players, and changing its extension to .at3 or another audio suffix does not convert the data.