Add your AU file
Drop one or more .au 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.
AU to OGG
Re-encoding .au audio as .ogg changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
100% private for supported formats
Runs on your deviceConvert supported files
Drop AU 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 Sun audio to Ogg audio
Re-encoding .au audio as .ogg changes how the sound is compressed and which players will accept it. 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.
An .ogg file almost always means Vorbis-compressed audio in the Ogg container, the free-software world's answer to MP3. The .ogg extension originally covered any Xiph media; audio kept the name when video moved to .ogv, and game developers and Wikipedia still lean on it heavily. For this route the practical draw is patent-free from its first release and strong quality at mid-range bitrates — balanced against apple's Music app and iOS offer no native playback, which is worth knowing before you commit a large batch.
Why convert AU to OGG?
The practical trigger for this conversion is usually a mismatch: with .au, essentially obsolete outside legacy systems. Switching to .ogg buys you patent-free from its first release, which is why it is the better fit for shipping game audio assets without codec royalties. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
AU vs OGG at a glance
| Aspect | Sun audio (.au) | Ogg audio (.ogg) |
|---|---|---|
| Format type | Lossless — every pixel or sample is preserved exactly | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | a 24-byte header carries a '.snd' magic number, data offset, encoding type, sample rate, and channel count | vorbis is an MDCT-based lossy codec tuned through a quality scale (-q) rather than fixed bitrates |
| Strongest at | maintaining sound assets in vintage Unix and Java software | shipping game audio assets without codec royalties |
| Weak spot | essentially obsolete outside legacy systems | apple's Music app and iOS offer no native playback |
| Metadata | an optional annotation field in the header can hold a short text string; no formal tag structure exists | vorbis comments, the flexible key=value system shared with FLAC and Opus, plus METADATA_BLOCK_PICTURE for embedded cover art |
Pick OGG as the output
Select .ogg in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if OGG 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 OGG file. Outputs keep the original filename with the .ogg extension.
AU to OGG questions, answered
Will converting AU to OGG lose quality?
Some. Since au is lossless-oriented and ogg is lossy-oriented, the encoder will discard detail it judges least visible; the quality slider controls how aggressive that is. Keep the original .au if you may need a pristine master later.
Is it private to convert AU files here?
Yes — the .au 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 OGG file work?
Chrome, Firefox, and Edge have decoded Ogg Vorbis for many years, and Android plays it natively, while Safari and iOS remained the notable holdouts until only recently. Dedicated players such as VLC and foobar2000 cover the desktop everywhere.
Will the OGG file be bigger or smaller than my AU?
Smaller, usually dramatically so — that is the main reason this route exists. The quality slider trades size against fidelity; the default sits at the point where most people cannot spot the difference.
What happens to the metadata in my AU 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, an optional annotation field in the header can hold a short text string; no formal tag structure exists; none of it is transmitted anywhere because the file never leaves your browser.