Free online AUP3 to AIFF converter

What the AUP3 format is

.aup3 is the Audacity project format introduced with Audacity 3.x. It stores the project database, audio data, track arrangement, edits, labels, and project settings in one file. AUP3 is not a conventional audio file: media players and most audio editors cannot open it as a standalone recording.

You encounter AUP3 files after saving work in Audacity. The file remains editable in Audacity, but exporting is required to create a portable audio file such as AIFF.

What the AIFF format is

.aiff and .aif are Audio Interchange File Format files, commonly containing uncompressed PCM audio. AIFF preserves the exported sample data without lossy compression and is supported by many macOS applications, digital audio workstations, samplers, and mastering workflows.

AIFF files are substantially larger than compressed formats such as MP3 or AAC, but they avoid lossy encoding and support standard sample rates and bit depths used in production.

How to convert AUP3 to AIFF

Using Audacity

1. Install or open a compatible version of Audacity.
2. Choose File → Open and select the .aup3 project.
3. Allow Audacity to load the project, then check that the required tracks are enabled and that edits, effects, and volume automation sound correct.
4. Choose File → Export Audio.
5. Set the output filename and select AIFF (Apple/SGI) as the format. Use the file extension .aiff or .aif.
6. Set the destination, then click Export. Confirm the metadata dialog if it appears.
7. Open the exported file in an AIFF-compatible player or editor and check its duration, channels, sample rate, and audible result.

Audacity exports the audible project mix, not the editable Audacity project structure. If the project contains multiple tracks, the normal export creates one mixed AIFF file. To export separate tracks, use Audacity's track export options or mute and solo tracks before exporting.

You can also convert the file on the 101convert.com website for free without installing software. Uploading a project sends its contents to an online service, so use Audacity locally when the recording is confidential or the project is large.

Quality and compatibility considerations

Export does not recover quality that was already lost in the source recording. Choose the project or delivery sample rate and bit depth required by the receiving application; changing them during export resamples or changes the stored resolution. For production exchange, retain the original AUP3 file and export AIFF as a delivery copy.

AIFF normally contains uncompressed PCM and can be large. A stereo recording at 44.1 kHz and 24-bit uses roughly 15.9 MB per minute before metadata. AIFF does not preserve Audacity's undo history, plugins, effect settings, track lanes, or editable project layout.