Audio Conversion
Convert M4A to AU Online — Free
Fast, free M4A to AU converter. No registration required.
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How to Convert
1
Upload your .m4a 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 .au file when it's ready.
What is M4A?
M4A is an audio-only MPEG-4 container, commonly using AAC encoding. It provides better quality than MP3 at similar file sizes.
Format Details
- Full Name
- MPEG-4 Audio
- Extension
- .m4a
Key Features
- Better than MP3
- Apple ecosystem
- AAC encoding
- Metadata 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
M4A vs AU
| Feature | M4A | AU |
|---|---|---|
| Full Name | MPEG-4 Audio | Sun Microsystems Audio |
| Extension | .m4a | .au |
| Best For | Better than MP3 | Unix standard |
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.