AU Won't Open? Convert to ADTS Instantly
Fast, instant AU to ADTS conversion. No signup required. Just drop your .au file and get .adts in seconds.
Batch Settings
About AU to ADTS Conversion
Dealing with a AU file that won't open on your device? You're not alone — AU compatibility issues are one of the most common reasons people search for a file converter. AU is a widely used file format.
The fix is simple: convert your AU to ADTS. ADTS is a widely used file format. This conversion lets you convert between formats quickly, solving the problem in seconds rather than hours of troubleshooting.
Converting AU to ADTS maintains high quality with CocoConvert's optimised encoder settings.
CocoConvert processes your AU file on secure servers in Germany — upload, convert, download. Your files are encrypted via TLS and automatically deleted within 24 hours. No account needed, no software to install, and it works on any device with a browser.
This conversion is ideal when you When you need a ADTS file.
The conversion engine behind CocoConvert uses FFmpeg, Sharp, and qpdf — the same open-source libraries trusted by Netflix, YouTube, and enterprise platforms. Pro users can batch convert up to 100 files at once.
How to Convert AU to ADTS
- 1
Add your AU file
Drag and drop your .au file into the converter, or tap "Browse" to pick it from your device. Multiple files are supported for batch processing.
- 2
Pick ADTS output
Select .adts as the target format. CocoConvert automatically applies the best quality settings for this conversion.
- 3
Start conversion
Hit the Convert button. The audio engine processes your file server-side — no CPU drain on your device.
- 4
Save your file
Once done, download your .adts file. For batch jobs, download all at once as a zip.
What Happens When You Convert AU to ADTS
Your AU file is decoded and re-encoded as ADTS.
Your AU file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in ADTS format
The converted file is ready for download
Format Comparison
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
ADTS
.adts file
| Extension | .adts |
| MIME Type | audio/aac |
| Category | Audio |
Should You Convert AU to ADTS?
When to Convert
- ✓When you need a ADTS file
Frequently Asked Questions
Why won't my AU file open?
AU files may not open if your device lacks the right codec or application. Converting to ADTS — a more widely supported format — usually resolves this. ADTS is a widely used file format.
Is it safe to convert AU to ADTS online?
Yes. CocoConvert encrypts your file via TLS, processes it on isolated servers in Germany, and permanently deletes it within 24 hours. Your files are never shared or analysed.
Will I lose quality converting AU to ADTS?
Converting AU to ADTS maintains high quality with CocoConvert's optimised encoder settings. CocoConvert uses high-quality encoder defaults to preserve as much fidelity as possible.
How large can my AU file be?
Free users can convert files up to 250 MB each. Pro users get a 5 GB limit per file, and Business API users have custom limits.
Can I convert AU to ADTS on my phone?
Absolutely. CocoConvert works in any modern browser — iOS Safari, Android Chrome, and all desktop browsers. No app required.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.