Audio Conversion
Convert AU to AAC Online — Free
Fast, free AU to AAC converter. No registration required.
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How to Convert
1
Upload your .au file by dragging it into the upload area or clicking to browse.
2
Choose your output settings. The default settings work great for most files.
3
Click Convert and download your .aac file when it's ready.
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
What is AAC?
AAC is an audio coding standard designed to be the successor of MP3. It provides better sound quality at similar bit rates.
Format Details
- Full Name
- Advanced Audio Coding
- Extension
- .aac
Key Features
- Superior to MP3
- Streaming optimized
- Wide support
- Efficient compression
AU vs AAC
| Feature | AU | AAC |
|---|---|---|
| Full Name | Sun Microsystems Audio | Advanced Audio Coding |
| Extension | .au | .aac |
| Best For | Unix standard | Superior to MP3 |
Frequently Asked Questions
Yes. You can convert up to 5 files per day completely free, with no watermark or registration required.
Most files convert in under 30 seconds. Larger files (over 500MB) may take 1-3 minutes.
No. Our converter uses optimized encoding settings by default to preserve the original quality.
Free users can convert files up to 100MB. Pro users can convert files up to 2GB.
Yes. Our converter works in any modern web browser on any device.