OPUS
→
AU

Convert OPUS to AU Online

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

OPUS to AU Converter

Upload your OPUS file to convert it to AU format

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How to Convert OPUS to AU

Follow these simple steps

1

Step 1: Upload Your File

Upload your OPUS 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 OPUS to AU - Complete Guide

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

What changes when you convert OPUS 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 OPUS content with less aggressive compression.

About the OPUS format

Opus is a modern audio codec excellent for both voice and music. It offers superior quality at low bitrates and is widely used for VoIP and streaming.

  • Full name: Opus Audio Codec
  • Developer: IETF/Xiph.Org
  • Compression: Lossy compression
  • Opens with: browsers, VLC, messaging apps

Where OPUS is strong: best-in-class quality at low bitrates; open and royalty-free; ideal for voice and streaming.

Typical OPUS uses: voice chat and calls, low-bandwidth streaming, podcasts.

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

  • AU is less universally supported than OPUS — make sure your target player or platform accepts AU before converting.
  • One AU limitation to keep in mind: dated format rarely used today.

When to convert OPUS to AU

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

OPUS vs AU — format comparison

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

AttributeOPUSAU
TypeAudio fileAudio file
CompressionLossyFlexible (lossy or lossless)
Web-friendlyYesNo
Typical file sizeSmallMedium
Best forvoice chat and callslegacy Unix and Java system sounds

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Need the opposite conversion?

Convert AU to OPUS

Other OPUS Conversions

More formats you can convert OPUS to

Convert OPUS to MP3Convert OPUS to WAVConvert OPUS to AACConvert OPUS to OGGConvert OPUS to FLACConvert OPUS to M4AConvert OPUS to WMAConvert OPUS to AIFFConvert OPUS to AC3Convert OPUS to AMRConvert OPUS to CAFConvert OPUS to MKAConvert OPUS to WVConvert OPUS to SPXConvert OPUS to OGAConvert OPUS to DTSConvert OPUS to MP2
View all OPUS 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 AC3 to AUConvert AMR 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 →

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OPUS to AU FAQ

Converting OPUS to AU preserves the content faithfully; output also depends on the source file and any settings you choose.
Upload your OPUS 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 OPUS to AU conversion runs in your browser on any device — Windows, Mac, Linux, iOS, or Android — with uploads and downloads over HTTPS.
OPUS (Opus Audio Codec) is an audio file format. OPUS files can be played with various audio players and media applications.
Upload your OPUS 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 OPUS 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 OPUS 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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