Convert MP3 to AU Online — Free
Fast, free MP3 to AU converter. No registration required.
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How to Convert
Upload your .mp3 file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .au file when it's ready.
What is MP3?
MP3 is the most popular audio format worldwide. It uses lossy compression to reduce file size while maintaining acceptable audio quality for most listeners.
Format Details
- Full Name
- MPEG Audio Layer III
- Extension
- .mp3
Key Features
- Universal compatibility
- Small file sizes
- Streaming support
- ID3 tag support
What is AU?
AU is an audio format created by Sun Microsystems. It's one of the oldest digital audio formats, commonly used on Unix and Java platforms.
Format Details
- Full Name
- Sun Microsystems Audio
- Extension
- .au
Key Features
- Unix standard
- Java audio
- Simple format
- Legacy support
MP3 vs AU
| Feature | MP3 | AU |
|---|---|---|
| Full Name | MPEG Audio Layer III | Sun Microsystems Audio |
| Extension | .mp3 | .au |
| Best For | Universal compatibility | Unix standard |