.AUP File Extension
What is a AUP file?
An AUP file is an audio project file created by Audacity, a free audio-recording and editing program. It is saved in an XML format and contains references to audio files as well as any applied sound edits. AUP files are used for saving audio-editing work.
AUP files are saved with a corresponding folder named myproject_data, where myproject.aup is the project filename. This folder saves small chunks of audio data in an optimized, proprietary format that can be opened only by Audacity (these files use the .AU extension). When finished with sound editing, you can export an audio project to many different formats, including .WAV, .AIFF, .MP3, .M4A, and .WMA.
NOTE: With the release of Audacity 3.0, .AUP3 files replaced AUP files. You can open AUP files in Audacity 3.0 and later versions, but when you save your project, Audacity 3.0 will save the project as an AUP3 file.
How to open a AUP file
You can open an AUP file in Audacity (cross-platform). To do so, select File → Open... from the program's menu bar, and then navigate to and select your AUP file. The project your AUP file represents will then appear in Audacity.