# Convert AU to AMR

> Convert AU to AMR online for free in seconds. Files are processed in a secure, isolated sandbox and deleted automatically. No sign-up, no watermarks.

URL: https://www.converterrr.com/au-to-amr

- Runs in an isolated cloud sandbox with FFmpeg: files are deleted automatically, and the job uses cloud credits.
- Engines: FFmpeg (cloud).
- API: available. `POST /api/v1/jobs` with `"output_format": "amr"` (paid plans).
- More: [Audio converter](https://www.converterrr.com/audio-converter), [AU converter](https://www.converterrr.com/au-converter).

## How to convert AU to AMR

1. **Add your AU files.** Drag and drop AU files onto the converter, paste them, or click to browse. You can add several at once.
2. **Choose AMR.** AMR is already selected. Open Options if you want to change quality, size or metadata.
3. **Convert.** Click Convert. Files are processed in a secure cloud sandbox and are usually ready in seconds.
4. **Download your AMR.** Download each AMR file, or everything at once as a ZIP.

## Good to know

- We encode at a high-quality bitrate by default. Pick a specific bitrate or sample rate under Options.
- AU files are typically used for legacy Unix and Java applications, while AMR is best for voice recordings from older phones.
- This conversion runs on FFmpeg in an isolated cloud sandbox. Files are encrypted in transit and deleted automatically.

## AU vs AMR

|  | AU | AMR |
| --- | --- | --- |
| Full name | Sun Audio | Adaptive Multi-Rate |
| Type | Audio | Audio |
| Extensions | .au | .amr |
| MIME type | audio/basic | audio/amr |
| Best for | legacy Unix and Java applications | voice recordings from older phones |
| Properties | legacy format | lossy compression, legacy format |

**AU:** AU is a simple audio format introduced by Sun Microsystems, common on early Unix systems and Java.

**AMR:** AMR is a speech codec used by mobile phones for voice recordings and calls.

The other way around: [convert AMR to AU](https://www.converterrr.com/amr-to-au).

## Related conversions

- [AMR to AU](https://www.converterrr.com/amr-to-au) (in the browser)
- [AU to MP3](https://www.converterrr.com/au-to-mp3) (in the browser)
- [MP3 to AMR](https://www.converterrr.com/mp3-to-amr) (cloud)
- [AU to WAV](https://www.converterrr.com/au-to-wav) (in the browser)
- [MP4 to AMR](https://www.converterrr.com/mp4-to-amr) (cloud)
- [AU to M4A](https://www.converterrr.com/au-to-m4a) (in the browser)
- [WAV to AMR](https://www.converterrr.com/wav-to-amr) (cloud)
- [AU to FLAC](https://www.converterrr.com/au-to-flac) (in the browser)
- [MOV to AMR](https://www.converterrr.com/mov-to-amr) (cloud)
- [AU to AAC](https://www.converterrr.com/au-to-aac) (in the browser)
- [M4A to AMR](https://www.converterrr.com/m4a-to-amr) (cloud)
- [AU to OGG](https://www.converterrr.com/au-to-ogg) (in the browser)

## Convert AU to other formats

[AU to MP3](https://www.converterrr.com/au-to-mp3), [AU to WAV](https://www.converterrr.com/au-to-wav), [AU to M4A](https://www.converterrr.com/au-to-m4a), [AU to FLAC](https://www.converterrr.com/au-to-flac), [AU to AAC](https://www.converterrr.com/au-to-aac), [AU to OGG](https://www.converterrr.com/au-to-ogg), [AU to Opus](https://www.converterrr.com/au-to-opus), [AU to WMA](https://www.converterrr.com/au-to-wma), [AU to AIFF](https://www.converterrr.com/au-to-aiff), [AU to M4B](https://www.converterrr.com/au-to-m4b), [AU to AC3](https://www.converterrr.com/au-to-ac3), [AU to MP2](https://www.converterrr.com/au-to-mp2), [AU to WEBA](https://www.converterrr.com/au-to-weba), [AU to OGA](https://www.converterrr.com/au-to-oga), [AU to MKA](https://www.converterrr.com/au-to-mka), [AU to WV](https://www.converterrr.com/au-to-wv), [AU to TTA](https://www.converterrr.com/au-to-tta)

## Convert other formats to AMR

[MP3 to AMR](https://www.converterrr.com/mp3-to-amr), [MP4 to AMR](https://www.converterrr.com/mp4-to-amr), [WAV to AMR](https://www.converterrr.com/wav-to-amr), [MOV to AMR](https://www.converterrr.com/mov-to-amr), [M4A to AMR](https://www.converterrr.com/m4a-to-amr), [WebM to AMR](https://www.converterrr.com/webm-to-amr), [FLAC to AMR](https://www.converterrr.com/flac-to-amr), [MKV to AMR](https://www.converterrr.com/mkv-to-amr), [AAC to AMR](https://www.converterrr.com/aac-to-amr), [AVI to AMR](https://www.converterrr.com/avi-to-amr), [OGG to AMR](https://www.converterrr.com/ogg-to-amr), [WMV to AMR](https://www.converterrr.com/wmv-to-amr), [Opus to AMR](https://www.converterrr.com/opus-to-amr), [WMA to AMR](https://www.converterrr.com/wma-to-amr), [FLV to AMR](https://www.converterrr.com/flv-to-amr), [M4V to AMR](https://www.converterrr.com/m4v-to-amr), [MPEG to AMR](https://www.converterrr.com/mpeg-to-amr), [3GP to AMR](https://www.converterrr.com/3gp-to-amr), [AIFF to AMR](https://www.converterrr.com/aiff-to-amr), [MPG to AMR](https://www.converterrr.com/mpg-to-amr), [TS to AMR](https://www.converterrr.com/ts-to-amr), [M4B to AMR](https://www.converterrr.com/m4b-to-amr), [MTS to AMR](https://www.converterrr.com/mts-to-amr), [VOB to AMR](https://www.converterrr.com/vob-to-amr)

## AU to AMR: frequently asked questions

### How do I convert AU to AMR?

Drop your AU file onto the converter above, make sure AMR is selected, and click Convert. When it's done, download the AMR file — it usually takes a few seconds.

### Is it safe to convert AU to AMR here?

Yes. Your file is sent over an encrypted connection to an isolated sandbox that's created for your job only, then both the original and the result are deleted automatically.

### Is the AU to AMR converter free?

Yes. Cloud conversions like this one use credits, and you get free credits every day (3 without an account, 10 with a free account).

### Will converting AU to AMR reduce quality?

AMR is a lossy format, but our defaults are tuned to be visually indistinguishable for most files. You can raise the quality under Options.

### Can I convert multiple AU files at once?

Yes. Add up to 5 files at a time without an account, 10 with a free account and up to 500 on paid plans, then download them individually or as a single ZIP.

### Can I convert AMR back to AU?

Yes — use our AMR to AU converter. Note that converting back and forth between formats can't recover detail lost to lossy compression.