MKV to AU Converter
Processing entirely on your device — large files may take a moment.
MKV (Matroska) is the open container of choice for HD movies: it holds virtually any video/audio codec plus subtitles and chapters in one file. Converting AU to WAV preserves the samples in a format every modern tool reads.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How MKV compares to AU
| MKV | AU | |
|---|---|---|
| Compression | Any codec inside | µ-law or PCM |
| Quality | Preserved as-is | Mono voice-grade (µ-law) |
| Compatibility | Players excellent, devices mixed | Legacy Unix tools |
| Best for | Collections and multi-track video | Old system sounds and recordings |
How to convert MKV to AU
- 1
Select your files
Select your MKV video.
- 2
Convert instantly
The engine demuxes the container and encodes the audio track into your chosen format.
- 3
Download results
Download the AU audio — the video track is simply dropped.
About the MKV format
MKV (Matroska) is the open container that refuses to say no: virtually any video codec, multiple audio tracks, multiple subtitle streams, chapters, attachments and menu structure in one file. It became the de facto standard for movie rips, anime releases and personal archives precisely because nothing needs to be thrown away.
The same generosity is its compatibility risk: smart players (VLC, mpv) handle everything, but smart TVs, consoles and car systems choke on exotic codec combinations inside MKV. It is also not a streaming standard, so web delivery runs through its subset, WebM.
+ Strengths
- ✓Unlimited tracks: audio, subtitles, chapters, attachments
- ✓Open specification, no licensing
- ✓Ideal archival container — nothing is lost
! Limitations
- −Device playback is hit-or-miss outside smart players
- −Not web/streaming native
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
Why convert MKV to AU?
Converting makes sense where the strengths of AU meet what MKV cannot give you. Simple, lossless sample storage Meanwhile Device playback is hit-or-miss outside smart players One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this MKV to AU 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 MKV to AU?
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.
Will the audio track be kept?
Yes. The audio is carried over and re-encoded to the standard audio codec of AU, staying in sync with the video. If your MKV file has multiple audio tracks, the first one is used.
Why is video conversion slower than image conversion?
Every frame has to be decoded and re-encoded. This site runs that work on your own CPU via WebAssembly — nothing is uploaded, but a multi-minute video reasonably takes a few minutes. Images, by comparison, are single-frame jobs.