HotConvertDrop your files here
or click to select
Why convert AU to M4A?
Fast
Your file is converted in under 30 seconds in our cloud.
Secure
Files are automatically deleted after 1 hour.
Quality preserved
Maximum quality preserved during conversion.
About the AU format
AU — Sun Microsystems Audio Format
AU is a simple audio format developed by Sun Microsystems and used in Unix/Linux environments. It supports multiple audio encodings and was commonly used in Java applications and Unix systems.
Common uses
- Legacy Unix/Linux audio files
- Java audio applications
- System sounds
- Old internet audio clips
About the M4A format
M4A — MPEG-4 Audio
M4A is Apple's audio-only MPEG-4 container format, used by iTunes and Apple Music. It typically contains AAC audio and is functionally superior to MP3 at the same file size. It is the default export format from iTunes.
Common uses
- iTunes and Apple Music downloads
- iPhone voice memos
- Apple ecosystem audio files
- High-quality music purchases
Related conversions
Other conversions available for AU and M4A files
Frequently asked questions
Is the conversion free?
Yes, basic conversion is completely free. For large volumes, check out our paid plans.
What is the maximum file size?
Free accounts can convert files up to 25 MB. Pro accounts up to 100 MB.
How long are my files kept?
Files are automatically deleted after 1 hour on the free plan, 24 hours on Pro.
What formats are supported?
We support over 200 source and target formats. See our complete formats page.