Variation lets you hear what MP3 and Opus settings do to a track, live.

• Load a WAV. Pick MP3 or Opus. Change any setting while it plays and hear the result right away.
• Space plays and pauses. Hold C during playback to hear the original for an A/B check.
• The estimated output size updates as you change settings, before you export.
• Opus mode can simulate packet loss and show how PLC and in-band FEC recover from it.
• Runs in the browser. Files stay on your machine.

Drop a WAV anywhere on this page, or press Choose files at the bottom left.