Free online W64 to OPUS converter

Source format

W64 is an audio container format used by Wave64, an extension of the classic WAV format designed by Sony. It was created to overcome the 4 GB size limit of standard WAV files and is commonly used in professional audio workflows, especially for long recordings, multitrack sessions, and high-resolution PCM audio. W64 files are typically found in audio production, archiving, and editing environments where very large uncompressed audio files need to be stored reliably.

Target format

OPUS is a modern, highly efficient lossy audio codec standardized by the IETF. It is widely used for voice, streaming, online communication, and general-purpose audio distribution because it delivers excellent quality at low bitrates and handles both speech and music well. Compared with uncompressed formats like W64, OPUS produces much smaller files, making it ideal when file size and bandwidth matter more than preserving the original PCM data exactly.

How to perform the conversion

The best approach is to use a desktop audio tool that can read W64 and encode to OPUS. FFmpeg is usually the most reliable choice because it supports both formats and gives precise control over quality.

1. Install FFmpeg if it is not already available on your system.
2. Open a terminal or command prompt in the folder containing your W64 file.
3. Run a command such as ffmpeg -i input.w64 -c:a libopus output.opus.
4. If you want to control quality, add a bitrate setting such as -b:a 96k or -b:a 128k, for example: ffmpeg -i input.w64 -c:a libopus -b:a 128k output.opus.
5. Check the resulting OPUS file in a player that supports the format.

If you prefer a graphical editor, Audacity can open many W64 files and export to OPUS when the required encoder support is available. Typical steps are File → Open, then File → Export → Export as Opus. Some installations may require additional codec support before OPUS export is available.

You can also convert the file on the 101convert.com website for free, without installing any software.

Notes on quality and compatibility

W64 to OPUS is a lossy conversion. The original uncompressed audio data in W64 is not preserved exactly, so repeated re-encoding should be avoided. For best results, convert from the highest-quality source available and choose a bitrate appropriate for the content: lower bitrates are often fine for speech, while music usually benefits from higher settings.

Compatibility is another important factor. OPUS is widely supported in modern players, browsers, and communication apps, but some older hardware players and legacy software may not recognize it. If broad compatibility is required, consider whether a more universally supported format is needed. Also note that W64 files may contain very high sample rates or multichannel audio; these usually convert correctly, but the final quality depends on the encoder settings and the source material.