AU
→
OPUS

Convert AU to OPUS Online

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

AU to OPUS Converter

Upload your AU file to convert it to OPUS format

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How to Convert AU to OPUS

Follow these simple steps

1

Step 1: Upload Your File

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

2

Step 2: Select Output Format

OPUS 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 OPUS file when ready

Convert AU to OPUS - Complete Guide

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

What changes when you convert AU to OPUS

  • The audio is re-encoded into the OPUS format. Because re-encoding is not free, start from the highest-quality source you have and keep quality settings high.
  • OPUS is widely supported for streaming, browsers, and uploads, so the result plays on more devices and platforms than AU.
  • Expect a smaller output file: OPUS is typically more space-efficient than AU for the same content.

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.

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.

What OPUS keeps

  • OPUS adds: best-in-class quality at low bitrates.

Things to watch out for

  • One OPUS limitation to keep in mind: limited support in older hardware and apps.

When to convert AU to OPUS

  • Convert AU to OPUS for voice chat and calls.
  • Convert AU to OPUS for low-bandwidth streaming.
  • Convert AU to OPUS for podcasts.
  • Choose OPUS when a website, browser, or upload form rejects your AU file.

AU vs OPUS — format comparison

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

AttributeAUOPUS
TypeAudio fileAudio file
CompressionFlexible (lossy or lossless)Lossy
Web-friendlyNoYes
Typical file sizeMediumSmall
Best forlegacy Unix and Java system soundsvoice chat and calls

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Need the opposite conversion?

Convert OPUS to AU

Other AU Conversions

More formats you can convert AU to

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

Convert to OPUS

Other formats you can convert to OPUS

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

AU to OPUS FAQ

Converting AU to OPUS preserves the content faithfully; output also depends on the source file and any settings you choose.
Upload your AU file, confirm OPUS as the output format, and click Convert. Job status is shown while the file is processed, then you can download the OPUS 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 AU to OPUS 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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