AU to AIF Converter
Processing entirely on your device — large files may take a moment.
Convert AIF exactly as you would AIFF: to WAV for Windows tools, or to MP3/FLAC for sharing. If your files are still in AU format, this page is the shortcut: AU is the µ-law audio format of old Unix systems and Java applets — tiny mono files from another era.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How AU compares to AIF
| AU | AIF | |
|---|---|---|
| Compression | µ-law or PCM | Uncompressed PCM |
| Quality | Mono voice-grade (µ-law) | Bit-exact |
| Compatibility | Legacy Unix tools | Mac-first |
| Best for | Old system sounds and recordings | Mac recording and production |
How to convert AU to AIF
- 1
Select your files
Drag & drop your AU files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to AIF". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted AIF file individually, or grab everything at once as a ZIP archive.
About the AU format
AU is Sun Microsystems' audio format from the Unix workstation age: a small header followed by µ-law (or PCM) samples. Java's applet era shipped it everywhere, and old Unix sound tooling still emits it.
Modern players increasingly skip it. Converting AU to WAV preserves the samples bit-for-bit while moving the file into universal territory — the standard rescue path for system sounds and old recordings.
+ Strengths
- ✓Simple, lossless sample storage
- ✓Native to old Unix/Java tooling
! Limitations
- −µ-law flavor sounds dated and mono
- −Dropped by modern players
About the AIF format
AIFF is Apple's counterpart to WAV: uncompressed PCM in an IFF container, born with the classic Mac in 1988. It stores the same bit-perfect audio as WAV but carries metadata far better — iTunes-era tags, cover art and loop points all fit natively, which made it the default of Logic Pro and Mac-based audio production.
Functionally the WAV-versus-AIFF choice is platform history: same quality, same sizes, AIFF friendlier on Mac, WAV friendlier everywhere else. Converting between them is a lossless retagging exercise, nothing more.
+ Strengths
- ✓Bit-perfect uncompressed audio
- ✓Better metadata support than WAV
- ✓Native to macOS and Logic Pro
! Limitations
- −Same bulk as WAV (~10 MB/minute)
- −Windows tooling historically prefers WAV
Why convert AU to AIF?
There is a concrete reason this conversion exists: µ-law flavor sounds dated and mono AIF sidesteps that — Bit-perfect uncompressed audio If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this AU to AIF converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Is there a file size limit for AU to AIF?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.
Can I convert a whole folder of AU files?
You can select many files at once and they are processed in a single batch. Output files land in one ZIP download when there is more than one result.
Will converting AU to AIF reduce audio quality?
If AIF is lossless, the output contains everything the AU file contains — no further loss is added. If AIF is lossy, one recompression pass is unavoidable; the quality slider controls how much. Loss that already happened in the source file can never be undone by converting.