1
Choose Your Audio File
Choose the .opus file. Voice notes saved from WhatsApp on Android usually end in .opus.
Opus to MP3 Converter
Turn WhatsApp and Telegram voice notes and other Opus files into MP3. They are converted in your browser and never uploaded, which matters for private messages.
Files stay on your device
Drop your .opus file here, or choose a file
Converts Opus audio, including WhatsApp and Telegram voice notes, to MP3. It stays on your device.
Choose a fileYour browser converts the file. Nothing is sent to a server.
- No signup, no watermark
- No upload size limit
- About 2 sec for a 47 sec clip
- Works offline once loaded
How to Convert Opus to MP3
2
Pick Quality and Trim
Keep 128 kbps for voice notes; it is clear and keeps the MP3 small.
3
Convert and Download
Press Convert to MP3, play the preview, and download.
What Is an Opus File?
Opus is an open audio codec standardised by the IETF in 2012. It sounds clear at very low bitrates, which is why WhatsApp and Telegram use it for voice messages and many calling apps use it for speech.
An .opus file is Opus audio in an Ogg container. Phones play it inside the messaging app, but many players, editors and upload forms do not open it.
| Opus | MP3 | |
|---|---|---|
| Typical bitrate for voice | 16 to 32 kbps | 128 kbps |
| Size for 1 minute of voice | About 0.1 to 0.25 MB | About 1 MB |
| Made for | Calls and voice messages | Music and general audio |
| Plays on | Messaging apps, browsers | Every device and app |
Why Convert Opus to MP3
Keep Voice Notes
Save an important voice message as an MP3 you can play outside WhatsApp or Telegram, on any phone or computer.
Transcribe or Share
Transcription services, email and most apps accept MP3 where they refuse .opus.
Private by Design
Voice notes are personal. Here they are converted on your device and never sent to a server.
Why the MP3 Is Bigger Than the Voice Note
Opus is far more efficient than MP3 for speech. A voice note at about 24 kbps becomes a 128 kbps MP3, so the MP3 is several times larger, but it still sounds the same.
Choosing a higher bitrate will not improve the voice, because the detail was never in the original. 128 kbps is the right choice for voice notes.
Opus to MP3: Frequently Asked Questions
How do I convert a WhatsApp voice note to MP3?
Save or export the voice note so you have the .opus file, open this page, choose the file and press Convert to MP3.
Why is the MP3 larger than the Opus file?
Opus compresses speech much more than MP3 does. The MP3 needs a higher bitrate for the same sound, so it is several times bigger.
Is my voice note uploaded to a server?
No. Your browser reads the voice note and writes the MP3 on your own device. Nothing is sent to MP4toMP3.io or anyone else, and the page keeps working with Wi-Fi off once it has loaded.
Does Opus to MP3 work on iPhone?
It depends on the Safari version. If a file does not open, convert it on a computer or an Android phone in Chrome, Edge or Firefox.
Can I convert Telegram voice messages?
Yes. Telegram voice messages are Opus audio. Files ending in .ogg or .oga convert the same way.
Ready to Convert Opus to MP3?
Choose a file at the top. It is free, private and done in your browser in a few seconds.
Convert now