Tools / File Converter / AU to OPUS Converter

AU to OPUS Converter

Convert AU files to OPUS. Free, without uploading.

This tool converts AU files to OPUS. Sun/NeXT audio.

OPUS is a modern format that sounds great even at low bitrates. WhatsApp and Telegram voice messages use it. OPUS is lossy; you choose the quality from 96 to 320 kbps. 192–256 kbps is enough for music, 128 kbps for speech.

Conversion runs on your device; your file is never sent to a server. The components download once on first use, and later conversions start right away.

How to use

1. Choose the AU file, drag it in, or paste its link.
2. Choose the audio quality; optionally enter a start and end time.
3. Press "Convert" and download the OPUS file.

Frequently asked questions

Will audio quality drop when converting to OPUS?

OPUS is lossy, so there is a small loss you won’t hear at higher bitrates. If the source is already lossy, a higher bitrate won’t improve it.

Is there a file size limit?

No fixed limit; your device’s memory decides. Computers usually handle files up to 1–2 GB.

Is my file uploaded?

No. Your AU file is converted to OPUS inside your browser.