Opus to MP3 converter

WhatsApp voice notes and Opus recordings become universally playable as MP3. Your files stay on this device.

Drop Opus files here Files, a whole folder or a ZIP. Nothing leaves your device.

How to convert Opus to MP3

  1. Add your files. Drop Opus files anywhere on the page, or use Choose files. Folders and ZIP archives work too; every Opus inside is picked up.
  2. Check that MP3 is selected. MP3 is already chosen on this page. Other formats in the same row are one tap away if you change your mind.
  3. Adjust options if you need to. Choose a bitrate for lossy formats; WAV and FLAC need no settings.
  4. Convert and download. Press Convert. Each file shows its progress, then a Download button. With several files, “Download all” gives you a single ZIP.

What happens to your Opus

The audio is decoded and encoded again as MP3 at the bitrate you choose. Where your browser has no built-in encoder for MP3, a small open-source encoder compiled to WebAssembly is loaded instead.

Re-encoding one lossy format to another loses a little more detail each time, so pick a bitrate at least as high as the original’s.

About Opus and MP3

Opus: Opus is a modern open codec that sounds very good at low bitrates. WhatsApp voice notes and many calls use it.

MP3: MP3 is the universal lossy audio format. Every phone, car stereo and music app plays it.

Questions

Is my Opus file uploaded anywhere?

No. The conversion runs inside this browser tab using code served by this site, and the MP3 is created on your device. You can even disconnect from the internet once the page and its converter have loaded.

Will converting Opus to MP3 change the sound?

Lossless conversions sound identical. Converting to a lossy format such as MP3 discards detail you will rarely notice at 192 kbps or above. No conversion can add back quality that an earlier lossy encode removed.

Can I convert several Opus files at once?

Yes. Drop as many Opus files as you like, a whole folder or a ZIP. They convert one after another, and “Download all” saves every MP3 in one ZIP that keeps your folder structure.

Is there a file size limit?

There is no fixed limit, because nothing is uploaded. The practical limit is your device’s memory: a phone may struggle with very large files that a laptop converts easily.