AMR
→
AU

Convert AMR to AU Online

Convert AMR to AU online. Start with free daily conversions, no install, no watermarks, and visible job status.

AMR to AU Converter

Upload your AMR file to convert it to AU format

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How to Convert AMR to AU

Follow these simple steps

1

Step 1: Upload Your File

Upload your AMR file by dragging and dropping or clicking to browse

2

Step 2: Select Output Format

AU is automatically selected as the output format

3

Step 3: Start Conversion

Click the Convert button to start the conversion

4

Step 4: Download Result

Download your converted AU file when ready

Convert AMR to AU - Complete Guide

Converting AMR to AU stays in the audio file family but changes the traits that decide size, quality, transparency, editability, or device support. AMR is a audio format. Adaptive Multi-Rate. AU is a audio format. Sun audio. Below is what actually changes in a AMR→AU conversion, what is preserved, and when AU is the better choice than keeping AMR.

What changes when you convert AMR to AU

  • The audio is re-encoded into the AU format. Because re-encoding is not free, start from the highest-quality source you have and keep quality settings high.
  • Expect a larger output file: AU stores AMR content with less aggressive compression.

About the AMR format

AMR (Adaptive Multi-Rate) is an audio format optimized for voice recordings. It is commonly used by mobile phones for voice memos and recordings.

  • Full name: Adaptive Multi-Rate
  • Developer: 3GPP
  • Compression: Lossy compression
  • Opens with: VLC, QuickTime, FFmpeg

Where AMR is strong: very small files optimized for speech; the standard codec for mobile voice recordings; low bitrate ideal for narrow bandwidth.

Typical AMR uses: phone voice recordings, voicemail and push-to-talk audio, MMS voice messages.

About the AU format

AU is a audio format. Sun audio.

  • Compression: mixed
  • Opens with: VLC, Audacity, FFmpeg

Where AU is strong: simple legacy format from Sun/NeXT systems; stores uncompressed PCM or companded mu-law/A-law audio; easy to read and parse.

Typical AU uses: legacy Unix and Java system sounds, older audio archives.

What AU keeps

  • AU adds: simple legacy format from Sun/NeXT systems.

Things to watch out for

  • One AU limitation to keep in mind: dated format rarely used today.

When to convert AMR to AU

  • Convert AMR to AU for legacy Unix and Java system sounds.
  • Convert AMR to AU for older audio archives.
  • Pick AU when you need stores uncompressed PCM or companded mu-law/A-law audio.

AMR vs AU — format comparison

A quick side-by-side of the structural differences between AMR and AU, so you can confirm this is the right conversion for your file:

AttributeAMRAU
TypeAudio fileAudio file
CompressionLossyFlexible (lossy or lossless)
Web-friendlyNoNo
Typical file sizeSmallMedium
Best forphone voice recordingslegacy Unix and Java system sounds

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Need the opposite conversion?

Convert AU to AMR

Other AMR Conversions

More formats you can convert AMR to

Convert AMR to MP3Convert AMR to WAVConvert AMR to AACConvert AMR to OGGConvert AMR to FLACConvert AMR to M4AConvert AMR to WMAConvert AMR to AIFFConvert AMR to OPUSConvert AMR to AC3Convert AMR to CAFConvert AMR to MKAConvert AMR to WVConvert AMR to SPXConvert AMR to OGAConvert AMR to DTSConvert AMR to MP2
View all AMR conversions →

Convert to AU

Other formats you can convert to AU

Convert MP3 to AUConvert WAV to AUConvert AAC to AUConvert OGG to AUConvert FLAC to AUConvert M4A to AUConvert WMA to AUConvert AIFF to AUConvert OPUS to AUConvert AC3 to AUConvert CAF to AUConvert MKA to AUConvert WV to AUConvert SPX to AUConvert OGA to AUConvert DTS to AUConvert MP2 to AU
View all AU conversions →

AMR to AU FAQ

Converting AMR to AU preserves the content faithfully; output also depends on the source file and any settings you choose.
Upload your AMR file, confirm AU as the output format, and click Convert. Job status is shown while the file is processed, then you can download the AU result.
Yes. You can start with free daily conversions, with no signup required for your first jobs and no watermarks on the output. Accounts and paid plans are available for higher-volume work.
No. The AMR to AU conversion runs in your browser on any device — Windows, Mac, Linux, iOS, or Android — with uploads and downloads over HTTPS.
AMR (Adaptive Multi-Rate) is an audio file format. AMR files can be played with various audio players and media applications.
Upload your AMR audio file to the converter, select your desired output format, and click Convert. The job status appears while the audio is processed.
You can start with free daily conversions. Accounts and paid plans are available for higher-volume work, and downloaded files are not watermarked.
You can convert AMR to proof-backed audio outputs such as MP3, WAV, AAC, OGG, FLAC, M4A, WMA, AIFF, OPUS, AC3, AMR, AU, CAF, MKA, WV, SPX, OGA, DTS, and MP2 when the source format is public-supported.
Yes! Our AMR converter works on any device including smartphones and tablets.
Choose the bitrate or output setting that fits your file-size and playback needs. Lossy formats can reduce detail compared with the source.

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