Convert anything, at global scale.
200+ formats and automation APIs that feels instant.
CONVERT
From
To
Drop files or choose a source
Upload multiple files at once, mix formats, and fine-tune every conversion with format-aware settings.
Max 2GB per file · Drag & drop ready · Mixed file types welcome
AU at a glance
AU
AU belongs to an earlier multimedia era where workstation and Unix vendors often had their own practical audio defaults.
CAF at a glance
CAF
CAF reflects Apple's effort to modernize audio packaging for pro and system workflows inside its own platform stack.
Format comparison
| Feature | AU | CAF |
|---|---|---|
| File type | Audio | Audio |
| Extensions |
|
|
| MIME type |
|
|
| Compression / quality | depends | depends |
| File size characteristics | medium | medium |
| Compatibility | broad | broad |
| Editability | limited | limited |
| Created year | 1987 | 2005 |
| Inventor | Sun Microsystems | Apple |
| Status | active | active |
| Primary use cases |
|
|
| Common software |
|
|
| Archival suitability | moderate | moderate |
| Metadata handling | moderate | moderate |
| Delivery profile | strong | strong |
| Workflow fit | delivery | delivery |
| Multitrack support | Not supported | Not supported |
| HDR support | Not supported | Not supported |
| Streaming ready | Not supported | Not supported |
When to use each format
When to use AU
- capture ingest
- editing and mastering
- streaming or playback delivery
- Historically important in Unix/workstation audio.
When to use CAF
- capture ingest
- editing and mastering
- streaming or playback delivery
- Flexible container for Apple audio workflows.
FAQs
Why convert AU to CAF?
Choose CAF as target when working inside Apple audio pipelines, especially for long recordings, app assets, sound libraries, or technical workflows that benefit from Core Audio compatibility.
What changes when converting AU to CAF?
Convert to CAF when working inside Apple audio pipelines, especially for long recordings, app assets, sound libraries, or technical workflows that benefit from Core Audio compatibility. It is a good target when AIFF or WAV limitations are inconvenient but Apple tooling is the primary consumer. For general exchange, WAV, AIFF, or M4A are usually easier handoff formats.
What should I review after converting AU to CAF?
After conversion, review these destination checks: Open converted output in Core Audio tools and verify behavior on real samples; Compare output against the expected depends quality profile; More niche outside Apple ecosystems.
How can I keep quality stable in AU to CAF conversion?
Run representative samples, keep settings deterministic, and monitor these risks: Often normalized into WAV or other common interchange formats; More niche outside Apple ecosystems; Validate destination compatibility before large-batch conversion.