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AUDIO

AU to M4A Converter — Free, Online, No Signup

Convert AU files to M4A online with no signup required.

Reverse conversion

AU at a glance

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M4A at a glance

M4A

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Format comparison

Feature	AU	M4A
File type	Audio	Audio
Status	active	active
Primary use cases	capture ingest editing and mastering streaming or playback delivery	capture ingest editing and mastering streaming or playback delivery
Multitrack support	Not supported	Not supported
HDR support	Not supported	Not supported
Streaming ready	Not supported	Supported

When to use each format

When to use AU

Your source file is already in AU.
Preserve source expectations before exporting to M4A.
AU is commonly used in audio workflows.

When to use M4A

Your target workflow expects M4A.
Improve delivery compatibility with M4A.
M4A is commonly used in audio workflows.

FAQs

Why convert AU to M4A?

This conversion is usually chosen when M4A fits downstream audio delivery better.

What changes when converting AU to M4A?

This conversion changes how the format behaves in downstream tools and delivery environments.

Moving to M4A adds streaming delivery.

What should I review after converting AU to M4A?

Validate output quality on representative files and confirm the target format behaves correctly in the destination workflow.

Format resources

AU M4A