OPUS to Text: Convert WhatsApp Voice Notes

You exported a WhatsApp chat and found a folder full of .opus files. What are they, why does WhatsApp use this format, and how do you turn them into readable text?

What is an .opus file

Opus is an audio codec designed for interactive speech and music. It was developed by the Internet Engineering Task Force (IETF) and is an open, royalty-free format.

WhatsApp uses Opus for voice messages because it:

• Compresses audio efficiently (small file sizes)
• Maintains good speech quality at low bitrates
• Is optimized for real-time voice communication
• Works across all platforms (iOS, Android, Web)

When you record a voice note in WhatsApp, it is saved as an .opus file.

What .opus files look like in a WhatsApp export

When you export a WhatsApp chat with media included, the .zip contains:

```

WhatsApp Chat - Group Name/

├── _chat.txt

├── 00000001-AUDIO-2024-03-15-09-30-22.opus

├── 00000002-AUDIO-2024-03-15-10-45-11.opus

├── 00000003-PHOTO-2024-03-15-11-00-33.jpg

└── ...

```

Each .opus file corresponds to a voice message in the chat. The filename contains a sequence number and timestamp.

In the _chat.txt file, voice messages appear as:

```

[15/03/2024, 09:30:22] Alice: <attached: 00000001-AUDIO-2024-03-15-09-30-22.opus>

```

Why you cannot just play .opus files

Most computers and phones can play .opus files with the right app. VLC, for example, handles Opus natively. But playing each voice note one by one and taking notes is impractical when you have 20 or 50 voice messages.