Add your WAV file
Drop one or more .wav files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
WAV to AU
Re-encoding .wav audio as .au changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop WAV files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting WAV audio to Sun audio
Re-encoding .wav audio as .au changes how the sound is compressed and which players will accept it. A .wav file is Microsoft's Waveform Audio format, which in practice almost always stores uncompressed PCM samples. Because every bit of the original signal is preserved and no decoding is required, .wav remains the default working format in recording studios and audio editors.
An .au file is the Sun audio format, one of the earliest structured audio files, created for Unix workstations. A minimal header followed by sample data, classically 8 kHz mu-law telephony audio, makes .au about as simple as an audio format can get. For this route the practical draw is so simple that nearly any audio tool can parse it and pCM variants preserve the recording exactly — balanced against essentially obsolete outside legacy systems, which is worth knowing before you commit a large batch.
Why convert WAV to AU?
The practical trigger for this conversion is usually a mismatch: with .wav, enormous compared with FLAC, which halves the size losslessly. Switching to .au buys you so simple that nearly any audio tool can parse it, which is why it is the better fit for maintaining sound assets in vintage Unix and Java software. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
WAV vs AU at a glance
| Aspect | WAV audio (.wav) | Sun audio (.au) |
|---|---|---|
| Format type | Lossless — every pixel or sample is preserved exactly | Lossless — every pixel or sample is preserved exactly |
| How it stores data | a RIFF chunk container whose fmt chunk usually declares linear PCM, though compressed codecs are technically permitted | a 24-byte header carries a '.snd' magic number, data offset, encoding type, sample rate, and channel count |
| Strongest at | capturing and mixing sessions in a DAW | maintaining sound assets in vintage Unix and Java software |
| Weak spot | enormous compared with FLAC, which halves the size losslessly | essentially obsolete outside legacy systems |
| Metadata | rIFF INFO chunks hold basic tags, while the Broadcast Wave bext chunk and iXML add description, originator, and timecode for production workflows; some tools also embed ID3 chunks | an optional annotation field in the header can hold a short text string; no formal tag structure exists |
Pick AU as the output
Select .au in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if AU is selectable, the route is real and validated.
Convert on your device
Press Convert. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid AU file. Outputs keep the original filename with the .au extension.
WAV to AU questions, answered
Will converting WAV to AU lose quality?
Both sides are re-encoded, so expect a small generation loss controlled by the quality setting: wav is lossless-oriented and au is lossless-oriented. For visually or audibly transparent results keep quality high; for smaller files lower it and compare.
Is it private to convert WAV files here?
Yes — the .wav file is processed inside your browser tab and never uploaded. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device. Close the tab and the file is gone from memory.
Where will the AU file work?
Audio tools such as Audacity, sox, and ffmpeg open .au readily, and Java's sound APIs still accept it. Consumer players, phones, and browsers dropped meaningful support long ago, so conversion to WAV or MP3 is the practical route.
Will the AU file be bigger or smaller than my WAV?
It depends on the content: a 24-byte header carries a '.snd' magic number, data offset, encoding type, sample rate, and channel count. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my WAV file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, rIFF INFO chunks hold basic tags, while the Broadcast Wave bext chunk and iXML add description, originator, and timecode for production workflows; some tools also embed ID3 chunks; none of it is transmitted anywhere because the file never leaves your browser.
Can I convert AU back to WAV?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .wav → .au → .wav is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.