Tools / File Converter / OPUS to AU Converter

OPUS to AU Converter

Convert OPUS files to AU. Free, without uploading.

This tool converts OPUS files to AU. OPUS is a modern format that sounds great even at low bitrates. WhatsApp and Telegram voice messages use it.

Sun/NeXT audio. AU is lossless, so the audio keeps the quality it has in the OPUS file.

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 OPUS 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 AU file.

Frequently asked questions

Will audio quality drop when converting to AU?

No. AU is lossless.

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 OPUS file is converted to AU inside your browser.