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WebM to AU - Online Audio Converter
Convert WebM to AU online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert WebM to AU
Drop WebM audio here or click to select
WebM
AU (PCM 16-bit)
About WebM to AU
Convert WebM to AU. WebM pairs VP9 video with Opus audio and supports an alpha channel. AU is Sun's simple container, usually holding 8 kHz telephony audio. Headers are minimal; verify sample rate after conversion..
Why convert WebM to AU?
- Larger files than lossy shares with AU uncompressed quality.
- Keep quality where supported.
- Private, no upload - runs in your browser.
WebM vs AU
| Animation | Yes | No |
|---|---|---|
| Transparency | Yes | No |
| Compression | lossy | uncompressed |
| Typical use | WebM pairs VP9 video with Opus audio and supports an alpha channel. | AU is Sun's simple container, usually holding 8 kHz telephony audio. |
When not to convert WebM to AU
- Skip AU for the smallest share: lossless output stays large, so prefer a lossy target when sending WebM files.
- Flatten transparency first: AU has no alpha channel, so composite WebM over a background color.
Limits
Starting point: WebM - VP9 video with Opus audio and alpha support. Apple editors accept it unevenly; keep MP4 for editing round-trips. Headers are minimal; verify sample rate after conversion. Encode AU (AU) from WebM at a bitrate near the source, and confirm the audio track before converting.
How conversion works
Conversion runs entirely in your browser with FFmpeg WASM. Files never leave your device.
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FAQ
How do I convert WebM to AU?
Drop your WebM file onto this page, choose quality and codec settings, then click Convert. The result downloads as AU instantly. All processing runs in your browser.
What codec is used for AU?
The default codec for AU is PCM 16-bit. You can change audio parameters in Advanced mode.
How do you store my files?
We do not store any processed audio. All conversion happens entirely in your browser using FFmpeg WASM.