FLAC to AU — Format Comparison & Online Converter
Fast, instant FLAC to AU conversion. No signup required. Just drop your .flac file and get .au in seconds.
Batch Settings
您手中的FLAC无损音乐，音质卓越，细节丰富，但在某些场合下，比如想在微信上分享给朋友，或者在一些老旧设备、特定游戏应用中播放，可能会遇到兼容性问题。AU格式，作为一种历史悠久的音频标准，以其广泛的兼容性和简洁的特性，在特定场景下依然扮演着重要角色。将FLAC转换为AU，并非意味着音质的妥协，而更多是为您的音乐寻找一条更顺畅的流通渠道。尤其是在考虑到移动端快速分享、旧系统支持或特定软件工作流时，AU格式的便捷性便凸显出来。我们提供高效、稳定的转换服务，确保您的音乐文件在格式转换后，依然保持良好的可用性，轻松应对各种播放环境。
- 微信分享老歌
- 旧版播放器兼容
- 游戏背景音乐
在大陆、台湾和新加坡地区，AU格式虽然不常见于日常消费级音乐，但在一些专业音频工具或旧有系统集成中仍有应用，转换后可确保更广泛的兼容性，尤其对于一些年代较久的设备或软件环境更为友好。
About FLAC to AU Conversion
FLAC (introduced 2001) and AU are both audio formats, but they differ in important ways. FLAC is lossless audio compression — bit-for-bit identical to the original at roughly 50-70% of WAV size. AU is a widely used file format.
When you convert FLAC to AU, the goal is to convert between formats quickly. Converting FLAC to AU maintains high quality with CocoConvert's optimised encoder settings. Understanding these technical differences helps you choose the right format for your workflow.
Your FLAC file is decoded and re-encoded as AU. The conversion involves 4 steps: (1) your flac file is uploaded and validated, (2) the file is decoded (parsed into its raw data), (3) the data is re-encoded in au 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 AU file. For the opposite direction, CocoConvert also supports AU to FLAC conversion.
How to Convert FLAC to AU
- 1
Upload .flac file
Select your FLAC file by dragging it to the upload zone or using the file picker. Batch upload is available for multiple files.
- 2
Choose .au
Set AU as the output format. The converter uses optimal settings based on the FLAC→AU conversion profile.
- 3
Convert
The server-side engine decodes your FLAC file and re-encodes it as AU. Processing time depends on file size and complexity.
- 4
Download result
Grab your converted .au file. Multiple output files can be downloaded together.
What Happens When You Convert FLAC to AU
Your FLAC file is decoded and re-encoded as AU.
Your FLAC file is uploaded and validated
The file is decoded (parsed into its raw data)
The data is re-encoded in AU format
The converted file is ready for download
Format Comparison
FLAC
.flac file
| Extension | .flac |
| MIME Type | audio/flac |
| Category | Audio |
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
Should You Convert FLAC to AU?
When to Convert
- ✓When you need a AU file
Frequently Asked Questions
What is the difference between FLAC and AU?
FLAC is lossless audio compression — bit-for-bit identical to the original at roughly 50-70% of WAV size. AU is a widely used file format.
Does FLAC to AU conversion affect quality?
Converting FLAC to AU maintains high quality with CocoConvert's optimised encoder settings.
Which format has better compression, FLAC or AU?
FLAC uses lossless compression. AU is widely supported. The better choice depends on whether you prioritize file size or quality.
How long does FLAC to AU 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 FLAC or AU better for long-term storage?
FLAC is better for archival since it's lossless.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.