AIFF vs AU — Comparison & Free Converter
Fast, instant AIFF to AU conversion. No signup required. Just drop your .aiff file and get .au in seconds.
Batch Settings
AIFF形式の音声ファイルをAU形式へ変換したいとお考えですか？ このページでは、高音質なAIFF音源を、より汎用性の高いAU形式へとスムーズに移行させるお手伝いをいたします。AIFFはApple製品でよく使われる非圧縮形式で、そのクリアな音質は音楽制作やプロフェッショナルなオーディオ編集で重宝されます。一方、AU形式はサン・マイクロシステムズが開発した形式で、特に古いUNIXシステムや一部のウェブブラウザで利用されることがあります。この二つの形式間の変換は、音源の互換性を広げ、様々な環境での再生を可能にする上で非常に有効です。大切な音源を、意図した場所で確実に再生できるよう、当社の変換ツールをぜひご活用ください。
- 古いPCゲームの音源を現代環境で再生
- UNIXベースのシステムでの音声ファイル利用
- ウェブサイトへの組み込み（特定ブラウザ向け）
日本のコンテンツ制作現場では、AIFFはその音質の高さからアニメやゲームのサウンドトラック制作で用いられることがありますが、AU形式への変換は、特定のレガシーシステム対応や、ごく一部のウェブ環境での配布時に検討されることがあります。
About AIFF to AU Conversion
AIFF or AU — which format should you use? The answer depends on your needs. Here's a quick breakdown.
AIFF is Apple's uncompressed audio format — equivalent to WAV in quality. It has mostly universal platform support. AU is a widely used file format. It has common platform support.
So when should you convert AIFF to AU? This conversion is ideal when you When you need a AU file. This conversion helps you convert between formats quickly.
Converting AIFF to AU maintains high quality with CocoConvert's optimised encoder settings.
If you've decided AU is the right choice, CocoConvert makes the conversion effortless. Upload your .aiff file, pick AU, and click Convert — done in seconds. The converter runs on secure servers in Germany, powered by FFmpeg, Sharp, and qpdf. Files are encrypted via TLS and erased within 24 hours.
Free tier: 5 files/hour, 250 MB each. Pro: 100 files/hour, 5 GB each. Works in every modern browser on desktop and mobile.
How to Convert AIFF to AU
- 1
Choose your AIFF file
Upload your .aiff file using drag-and-drop or the file browser. Batch mode lets you add multiple files.
- 2
Set format to AU
Select .au from the output options. The converter applies optimal quality settings automatically.
- 3
Run the conversion
Click Convert. Server-side processing means your device stays fast — even for large audio files.
- 4
Get your AU file
Download your converted file instantly. Batch downloads are available as a zip archive.
What Happens When You Convert AIFF to AU
Your AIFF file is decoded and re-encoded as AU.
Your AIFF 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
AIFF
.aiff file
| Extension | .aiff |
| MIME Type | audio/aiff |
| Category | Audio |
AU
.au file
| Extension | .au |
| MIME Type | audio/basic |
| Category | Audio |
Should You Convert AIFF to AU?
When to Convert
- ✓When you need a AU file
Frequently Asked Questions
Should I use AIFF or AU?
It depends on your goal. AIFF preserves full quality. AU preserves full quality. Choose based on whether file size or quality matters more for your use case.
Is AU higher quality than AIFF?
Not necessarily. Converting AIFF to AU maintains high quality with CocoConvert's optimised encoder settings. Quality depends on the compression type and settings, not just the format name.
Can I convert AIFF to AU on Mac and Windows?
Yes. CocoConvert is a web-based tool that works in all modern browsers — Chrome, Safari, Firefox, Edge — on any operating system including macOS, Windows, Linux, iOS, and Android.
Is CocoConvert free for AIFF to AU?
Yes. Free users get 5 conversions per hour (250 MB each). Pro subscribers unlock 100 files per hour, 5 GB per file, and priority processing.
What tools does CocoConvert use for AIFF to AU?
CocoConvert uses FFmpeg for audio/video, Sharp for images, and qpdf for documents — the same open-source libraries used by Netflix, YouTube, and major enterprise platforms.
Versions are pinned in our worker Dockerfile and re-built via CI on every change.