AU to W64 — Format Comparison & Online Converter
Fast, instant AU to W64 conversion. No signup required. Just drop your .au file and get .w64 in seconds.
Batch Settings
About AU to W64 Conversion
AU and W64 are both audio formats, but they differ in important ways. AU is a widely used file format. W64 is a widely used file format.
When you convert AU to W64, the goal is to convert between formats quickly. Converting AU to W64 maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your AU file is decoded and re-encoded as W64. The conversion involves 4 steps: (1) your au file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in w64 format, (4) the converted file is ready for download.
CocoConvert's converter handles the entire pipeline server-side using FFmpeg, Sharp, and qpdf — battle-tested libraries used by streaming platforms and enterprise tools. Files are encrypted in transit and deleted within 24 hours.
This conversion is ideal when you When you need a W64 file. For the opposite direction, CocoConvert also supports W64 to AU conversion.
How to Convert AU to W64
- 1
Upload .au file
Select your AU file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .w64
Set W64 as the output format. The converter uses optimal settings based on the AU→W64 conversion profile.
- 3
Convert
The server-side engine decodes your AU file and re-encodes it as W64. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .w64 file. Multiple output files can be downloaded together.
What Happens When You Convert AU to W64
Your AU file is decoded and re-encoded as W64.
Your AU file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in W64 format
The converted file is ready for download
Format Comparison
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
W64
.w64 file
| Extension | .w64 |
| MIME Type | audio/x-w64 |
| Category | Audio |
Should You Convert AU to W64?
When to Convert
- ✓When you need a W64 file
Frequently Asked Questions
What is the difference between AU and W64?
AU is a widely used file format. W64 is a widely used file format.
Does AU to W64 conversion affect quality?
Converting AU to W64 maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, AU or W64?
AU is a common audio format. W64 is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does AU to W64 conversion take?
Most conversions finish in seconds. Larger files or complex audio content may take 10–30 seconds. CocoConvert processes files in parallel for batch jobs.
Is AU or W64 better for long-term storage?
Both formats use lossy compression, so consider keeping your original source file for long-term storage.
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