WEBM to AU Converter
Processing entirely on your device — large files may take a moment.
WebM is Google’s royalty-free web video format (VP8/VP9 + Opus). It is small, streams beautifully, and every modern browser plays it natively. 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 WEBM compares to AU
| WEBM | AU | |
|---|---|---|
| Compression | VP9 / AV1 + Opus | µ-law or PCM |
| Quality | Efficient modern codecs | Mono voice-grade (µ-law) |
| Compatibility | All modern browsers | Legacy Unix tools |
| Best for | Web video and streaming | Old system sounds and recordings |
How to convert WEBM to AU
- 1
Select your files
Select your WEBM 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 WEBM format
WebM is Google's royalty-free video format for the web: a Matroska subset carrying VP8/VP9/AV1 video with Vorbis/Opus audio. YouTube serves most non-premium playback in VP9 WebM, and HTML5 `<video>` plays it natively in every modern browser — no licensing math required.
Efficiency is the selling point: VP9 and AV1 match or beat H.264/HEVC at the same quality for typical web content. Hardware decode is now widespread, though older Safari versions and some TVs remain the compatibility floor.
+ Strengths
- ✓Royalty-free codecs (VP9/AV1, Opus)
- ✓Native HTML5 video support
- ✓Efficient at web bitrates
! Limitations
- −Weaker support on older Safari/TVs
- −Not the default for camera or editor workflows
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 WEBM to AU?
Think of it as moving your file to the container that fits the job. Weaker support on older Safari/TVs AU works differently: Simple, lossless sample storage If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this WEBM 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 WEBM 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.
Does converting WEBM to AU re-encode my video?
Yes. The video is decoded and re-encoded with the settings chosen by the quality slider, which is what allows the format and size to change. For an archival copy, keep higher quality; for sharing, lower quality gives a much smaller file.
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 WEBM file has multiple audio tracks, the first one is used.