Convert MP3 to OPUS

Tested on Windows 11, 24 October 2026

Convert MP3 audio to OPUS in your browser or in the Filoshi app for Windows. OPUS is lossy: Filoshi uses a high-quality setting, and you can choose the bitrate. Nothing is uploaded.

Get Filoshi · $29Many files at once, no size limit, on Windows.

How to convert MP3 to OPUS in your browser

  1. 1
    Drop your MP3 file
    Drag it onto Filoshi above, or press Choose your MP3 file to pick it on your computer.
  2. 2
    Filoshi converts it
    OPUS is chosen already. FFmpeg, compiled to WebAssembly, converts it inside this browser tab.
  3. 3
    Save your OPUS file
    Download it when it is ready. Nothing was sent to a server.
Source format

What is MP3?

MPEG Audio Layer III (.mp3). MP3 is the most widely supported audio format. It uses lossy compression: sound the ear is unlikely to notice is thrown away, so a song takes a few megabytes. Every phone, car stereo and music app plays it.

Common use: Music, podcasts, audiobooks and general audio sharing

Output format

What is OPUS?

Opus Audio (.opus). Opus is an open, royalty-free codec standardised by the IETF in 2012. It sounds very good at low bitrates for both speech and music, and it is the codec of WebRTC video calls and many voice-message apps.

Common use: Voice messages, calls, streaming, podcasts

Questions about MP3 to OPUS

Is converting MP3 to OPUS free?
Yes, one file at a time: the converter on this page runs in your browser, files up to 100 MB, no sign-up. The Filoshi desktop app ($29 once, for Windows) converts many files at once and has no size limit.
Does converting MP3 to OPUS lose quality?
Yes, a little. OPUS is a lossy format, so some detail is thrown away when the file is saved. Filoshi uses a high-quality setting by default, and you can choose the bitrate in the file viewer. MP3 is lossy too, so this is a second round of compression; convert from the original, not from earlier conversions.
Is my MP3 file uploaded anywhere?
No. The converter on this page runs in your browser with FFmpeg compiled to WebAssembly; your MP3 file is read and converted on your device and never sent to a server. The desktop app works the same way, offline.
Has MP3 to OPUS been tested?
Yes. MP3 to OPUS is one of the 1,841 conversions that passed Filoshi's automated test matrix on Windows 11.
Can I convert many MP3 files at once?
Yes, in the desktop app. Drop as many MP3 files as you like on the window, pick OPUS once for all of them, and each file shows its own progress. The new files appear next to the originals, which are never changed.

Related conversions

Other MP3 conversions

MP3 to AACMP3 to OGGMP3 to FLACMP3 to M4AMP3 to AIFFMP3 to AC3MP3 to AUMP3 to CAF

Convert to OPUS

WAV to OPUSAAC to OPUSOGG to OPUSFLAC to OPUSM4A to OPUSWMA to OPUSAIFF to OPUSALAC to OPUS

Need MP3 to OPUS for many files?

The browser converter handles one file at a time. The Filoshi app for Windows converts as many as you drop, runs offline, and has 1,841 tested conversions.

Get Filoshi · $29