.AU File Extension

.AU File Extension

2 file types use the .au file extension.
File Type 1

Audacity Audio File

Developer Audacity
Popularity
3.7  |  24 Votes
Category Audio Files
Format Binary

What is a AU file?

An AU file is an audio file created by Audacity, a free, cross-platform audio editor. It is saved in a proprietary audio format used only by Audacity. AU files are part of Audacity projects, which are saved as .AUP files.

More Information

When you create or import an audio file into an Audacity project, Audacity automatically converts the file into an AU file. Each project's AU files are stored in that project's folder, which is named myproject_data.

The myproject_data folder also contains your project's AUP file, which is named myproject.aup. When you open your AUP file in Audacity, Audacity automatically searches for and loads the AU files your project includes. If you've moved an AU file that was previously stored in the myproject_data folder, Audacity will show an error message when you open your AUP file.

After you've finished editing your Audacity project, you can export the audio the project contains as an .MP3, .WAV, .M4A, or other common audio file. This is the easiest way to convert the audio saved in an AU file into an audio file that can be played in other audio players.

NOTE: As of version 3.0, Audacity no longer saves AU files that users can access. Instead, Audacity saves all of a project's files within a single .AUP3 file, instead of within a myproject_data folder.

How do I open a AU file?

AU files are not meant to be opened individually. Instead, you should open the Audacity (cross-platform) project that uses your AU file. To do so, select File → Open... from Audacity's menu bar. Then, open the AUP file that is stored alongside your AU file, in your project's myproject_data folder.

Open over 400 file formats with File Viewer Plus.Free Download

Programs that open AU files

Windows
Mac
Linux
Updated March 19, 2021
File Type 2

Audio File

Developer N/A
Popularity
2.9  |  11 Votes
Category Audio Files
Format Binary

What is a AU file?

Audio file introduced by Sun Microsystems; used primarily on Sun or other Unix-based machines and has been adopted by several audio programs, including Adobe Audition and QuickTime; stores the data in three parts: a header (24 bytes), a variable length annotation block, and the actual audio data.

Programs that open AU files

Updated December 31, 2014

Verified by FileInfo.com

The FileInfo.com team has independently researched all file formats and software programs listed on this page. Our goal is 100% accuracy and we only publish information about file types that we have verified.

If you would like to suggest any additions or updates to this page, please let us know.