AU to OGG Converter

Convert AU to OGG Online

Move a legacy Sun .au (or .snd) recording into OGG, the open Xiph.Org container that game engines, open-source tooling and the modern web all understand. The output is encoded with Vorbis by default — the royalty-free codec .ogg is best known for — turning a Unix-workstation relic with no metadata and patchy player support into a small, taggable, widely decoded file. What the conversion cannot do is add fidelity, and with AU that matters more than usual: the classic Sun payload is telephone-grade 8-bit µ-law, and no encoder brings back what companding threw away.

How to Convert AU to OGG

1. Upload Your AU File: Drag and drop your .au or .snd file onto the page, or click "+ Add Files" to browse. Sun/SPARCstation system sounds, early Java applet audio and old Unix speech archives all work, and several files can be queued and converted with the same settings.
2. Choose How the Audio Is Sized: Under File Compression pick Quality Preset and choose from the dropdown (Highest through Lowest, with "Very High (Recommended)" as the labelled sweet spot), or switch to Custom Bitrate (starts at 128 Kbps), Constant Bitrate (a fixed list of rates, where Vorbis works reliably between roughly 32 and 320 kbps) or Specific file size, which searches for the highest bitrate that still fits under the size you type in.
3. Set Audio Sample Rate, Audio Channel or Trim (Optional): Audio Channel can downmix to mono — worth doing for speech, since it roughly halves the data the encoder has to spend bits on. Audio Sample Rate offers ORIGINAL plus fixed rates; see the note below about what Vorbis accepts. Trim takes a Start time and Duration in seconds or HH:MM:SS.sss.
4. Convert and Download: Click Convert and save the .ogg file individually or as a ZIP. Files upload over an encrypted connection, are converted on our servers and are deleted automatically a few hours later. No sign-up, no watermark.

Which Codec Goes Inside the .ogg

Ogg is a container, not a codec — the Audio Codec control decides what actually gets written into it. Vorbis is the default and the right answer for most people.

What Vorbis Can and Cannot Do With Your AU Source

AU files come in two very different flavours and the outcome depends entirely on which one you hold. Vorbis is lossy: it stores audio efficiently, never adds detail the original capture lacked.

One pipeline detail worth knowing before you convert: we restrict Vorbis encoding to 22,050, 32,000, 44,100 and 48,000 Hz, because libvorbis becomes unreliable at very low sample rates paired with higher bitrates. A classic 8 kHz µ-law AU is therefore resampled up to 22,050 Hz on the way in, whether you leave Audio Sample Rate on ORIGINAL or pick 8000 HZ yourself. That resampling costs nothing in quality — it simply cannot add any either.

Frequently Asked Questions

Will converting my AU file to OGG improve the sound quality?

No, and no format can. If the AU holds the classic 8-bit µ-law or A-law payload (Sun's companded default at 8 kHz mono), Vorbis reproduces that intelligibility efficiently but cannot restore the highs and dynamic range the compander discarded when the recording was first made. If it holds linear PCM, you get a clean first-generation encode of an effectively lossless master — that is the case where OGG shines. What you gain either way is size, tagging and software support, not fidelity.

Why does my 8 kHz AU come out at 22,050 Hz in the OGG?

Because that is the lowest rate we let libvorbis encode at. Vorbis is technically capable of 8 kHz, but the encoder behaves unpredictably at very low sample rates when a higher bitrate is requested, so our pipeline snaps any requested or detected rate to the nearest of 22,050, 32,000, 44,100 or 48,000 Hz — and 8,000 lands on 22,050. The audio is resampled, not re-synthesised: it still contains only what the 8 kHz original captured, and it sounds the same. If keeping the literal 8 kHz rate matters to you, AU to Opus accepts 8, 12, 16, 24 and 48 kHz, and AU to FLAC preserves the source rate exactly.

Should I encode the OGG with Vorbis or Opus?

For anything that expects a .ogg, keep Vorbis. It is what game engines such as Unity, Unreal and Godot consume, what a great deal of open-source software assumes when it sees the extension, and what the widest range of existing .ogg tooling reads without complaint. Opus is the better codec on the numbers — more efficient at every bitrate and dramatically better for speech below 64 kbps — so pick it when the destination is new voice or streaming work rather than an existing Ogg pipeline. For a plain .opus file, use AU to Opus instead.

What bitrate should I pick for the OGG?

Less than instinct suggests, because the source usually cannot justify much. A µ-law AU is a 64 kbps stream to begin with and holds nothing above roughly 4 kHz, so 48–64 kbps mono captures all of it and higher settings only inflate the file. A 16-bit/44.1 kHz linear-PCM AU is a genuine master, and 96–128 kbps stereo Vorbis is transparent for most listeners on most material. When in doubt, leave Quality Preset alone and let the encoder scale to the source rather than forcing a number.

What plays an .ogg file?

VLC, foobar2000, Audacity, Winamp, Clementine and most Linux desktop players open Ogg Vorbis natively, and Firefox, Chrome and Edge play it in the <audio> element. Android has supported Vorbis since its early releases. The notable holdout is Apple: Safari and the stock iOS/macOS players do not play Ogg Vorbis, so if the file is destined for an iPhone or Apple Music, convert to AU to M4A or AU to MP3 instead.

Is converting an old Unix AU to OGG actually worth it?

More than most legacy conversions, yes — this is a genuine modernisation rather than swapping one dated wrapper for another. A Sun/NeXT workstation relic carrying audio/basic, with no tag fields and support limited to VLC-class tools, becomes an open, royalty-free file that current software actively reads and that can carry title, artist and album metadata. You trade a small amount of fidelity (nothing at all, on a µ-law source) for a file the modern ecosystem understands.

I want a lossless archive — is OGG the right target?

No. Vorbis discards data by design, which makes it the wrong choice for preservation. If your .au holds linear PCM and you care about the master, keep the original file, or convert with AU to FLAC for lossless compression with tagging, or AU to WAV for a plain uncompressed working copy — both preserve every sample exactly. For a µ-law AU there is little to preserve beyond the speech itself, so a low-bitrate OGG is usually all anyone needs.

Can I convert the OGG back to AU later?

Yes, OGG to AU reverses the direction, but it is not a round trip to the original quality. Once audio has been through Vorbis, rebuilding an .au around it wraps already-lossy audio in an older container — and our AU output defaults to 8-bit G.711 µ-law unless you choose a PCM encoding, which would compand it again on top. Keep the source .au if you may need its fidelity later.

How are my files handled, and how long do you keep them?

Your file is uploaded over an encrypted connection, converted on our servers, and deleted automatically a few hours after the job finishes — never shared, never made public, with no sign-up and no watermark. The practical limit on long recordings is upload size and time rather than the encode: a 60-second 8 kHz mono µ-law AU is only about 480 KB, while a 60-second 16-bit/44.1 kHz stereo PCM AU is about 10.6 MB before Vorbis compresses it.