File Converter

Opus to MP3 converter Free, private, no upload.

Convert Opus files to MP3 right in your browser. MP3 plays on every device, car stereo, media player and app, and keeps file sizes small. Your files are never uploaded.

or drop files anywhere · paste with Ctrl/⌘ + V

How to convert Opus to MP3

  1. 1 Drop your Opus files onto the page, or click “Choose files”. You can add many at once, or a whole folder.
  2. 2 MP3 is already selected as the output. Optionally open Options to adjust bitrate, sample rate, channels.
  3. 3 Click Convert, then Save. Converting several files? Save them all as one ZIP.

About the formats

Opus · Opus audio

Opus is a modern open audio codec with excellent quality at low bitrates. WhatsApp voice messages and many VoIP apps use it.

MP3 · MPEG Audio Layer III

MP3 is the most widely supported audio format, using lossy compression to keep music and podcasts small.

The conversion runs on your device using FFmpeg compiled to WebAssembly. You can adjust: bitrate, sample rate, channels, normalise loudness, start at, end at.

Frequently asked questions

How do I convert Opus to MP3?

Drop your Opus files onto the page, or click “Choose files”. You can add many at once, or a whole folder. MP3 is already selected as the output. Optionally open Options to adjust bitrate, sample rate, channels. Click Convert, then Save. Converting several files? Save them all as one ZIP.

Are my files uploaded to a server?

No. The conversion runs entirely in your browser using WebAssembly. Your files never leave your device, so it is safe for private photos, contracts and business data. Once the page has loaded it even works offline.

Will converting Opus to MP3 reduce quality?

MP3 uses lossy compression, so some detail is traded for a smaller file. At the default quality the difference is very hard to see or hear, and you can raise the quality setting if you need more.

Can I convert multiple Opus files to MP3 at once?

Yes. Add as many Opus files as you like; they are converted in parallel on your device and you can download them all as a single ZIP.

Is it free? Are there limits?

It is free, with no sign-up, no watermark and no daily limits. Because nothing is uploaded there is no upload size limit either; the only limit is your device’s memory, which matters mostly for very large videos.

See everything the Opus converter and the MP3 converter can do.