| Opus | MP3 | |
|---|---|---|
| Compression | Lossy | Lossy |
| Metadata | - | ✓ |
| Open / royalty-free | ✓ | ✓ |
| Defined by | - | - |
| Since | 2012 | 1993 |
| Best for | voice, podcasts, low-bandwidth streaming | music and podcasts for any device |
Opus
The best quality per kilobyte, especially for speech. What WhatsApp and Discord use.
MP3
The universal lossy audio format.
Questions
Opus or MP3: which is smaller?
It depends on the content; see our measured benchmarks on the conversion pages.
Can I convert Opus to MP3?
Yes, in your browser, nothing uploaded.
And MP3 to Opus?
Yes, as well.