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AU to AMR - Online Audio Converter
Convert AU to AMR online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert AU to AMR
Drop AU audio here or click to select
AU
AMR (AMR-NB)
About AU to AMR
Convert AU to AMR. AU is Sun's simple container, usually holding 8 kHz telephony audio. AMR encodes narrowband speech for GSM calls at 12.2 kbps and below. Tuned for voice calls, so music loses detail by design..
Why convert AU to AMR?
- Smaller files with AMR lossy compression.
- Keep quality where supported.
- Private, no upload - runs in your browser.
AU vs AMR
| Codec | PCM 16-bit | AMR-NB |
|---|---|---|
| Compression | uncompressed | lossy |
| Sample behavior | Full quality kept | Quality set by bitrate |
| Typical use | AU is Sun's simple container, usually holding 8 kHz telephony audio. | AMR encodes narrowband speech for GSM calls at 12.2 kbps and below. |
When not to convert AU to AMR
- Skip AMR for archival masters: lossy compression discards detail, so keep the AU original.
- Keep a master copy: repeated exports stack small losses, so archive AU before batch AMR shares.
Limits
Starting point: AU - AU is Sun's simple container, usually holding 8 kHz telephony audio. Headers are minimal; verify sample rate after conversion. Tuned for voice calls, so music loses detail by design. Encode AMR (AMR-NB) from AU at 256k for music or 128k for speech, starting from the master.
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 AU to AMR?
Drop your AU file onto this page, choose quality and codec settings, then click Convert. The result downloads as AMR instantly. All processing runs in your browser.
What codec is used for AMR?
The default codec for AMR is AMR-NB. 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.