Free online AT3 to AAC converter

Source format: AT3

AT3 usually refers to ATRAC3 audio, a compressed Sony audio format used in some PlayStation Portable (PSP) games, Sony devices, and older media archives. It is commonly found in game sound files, cutscenes, and bundled audio assets where smaller file size mattered more than universal compatibility. AT3 is not widely supported by everyday players, so it is often converted for easier playback and editing.

Target format: AAC

AAC (Advanced Audio Coding) is a modern, efficient lossy audio format supported by most phones, computers, media players, and streaming platforms. It generally offers better compatibility than AT3 and good sound quality at moderate bitrates. AAC is a practical choice for music libraries, portable playback, and sharing audio across devices.

How to perform the conversion

The most reliable way to convert AT3 to AAC is to use a desktop audio tool that can decode ATRAC3 and re-encode to AAC. A common option is FFmpeg, which works on Windows, macOS, and Linux.

1. Install FFmpeg if it is not already available on your system.
2. Open a terminal or command prompt in the folder containing the AT3 file.
3. Run a command such as ffmpeg -i input.at3 -c:a aac -b:a 192k output.m4a.
4. If you want an AAC stream in an .aac file instead of an .m4a container, use ffmpeg -i input.at3 -c:a aac -b:a 192k output.aac.
5. Play the result in a media player to confirm the audio sounds correct.

If you prefer a graphical workflow, you can also use audio editors or converters that support ATRAC3 input and AAC output, then choose File → Export or File → Save as and select AAC or M4A as the output format. On 101convert.com, you can convert the file online for free without installing any software.

Notes on quality and compatibility

AT3 is already compressed, so converting it to AAC will not restore lost audio detail. The best you can do is preserve the source quality by choosing a reasonable AAC bitrate, such as 128k to 192k for typical stereo audio. Avoid very low bitrates unless file size is the top priority.

For compatibility, .m4a is often the safest AAC container because it is widely recognized by players and devices. A raw .aac file can also work, but some apps prefer the .m4a wrapper. If the AT3 file comes from a game archive or is protected in a special container, you may need to extract the audio first before conversion.