maratoolHow to convert Opus (WhatsApp voice messages) to MP3
Voice apps save recordings as .opus files that most players can't open. Convert them to MP3 in your browser — nothing gets uploaded.
Use the free Opus to MP3 converter on maratool. The conversion runs on your own device via FFmpeg compiled to WebAssembly — important when the file is a private voice message you'd rather not send to a random server.
How it works
- Export the voice message — in WhatsApp, share or save the audio; you'll get a .opus file (Telegram and Discord exports work the same way).
- Drop it into the tool — .opus and .ogg both work.
- Convert and download — 128 kbps is plenty for speech; the MP3 plays on anything.
What is an .opus file, anyway?
Opus is the codec behind nearly every modern voice app — WhatsApp, Discord, Telegram, Signal. It compresses speech remarkably well, which is why a minute of voice message is only a few hundred kilobytes. The catch: media players, car stereos, and editing software often don't recognize it, so archiving or sharing recordings usually means converting to MP3 first.
Does the conversion lose quality?
Marginally. Opus and MP3 are both lossy, so re-encoding discards a little detail — but for voice recordings the difference is inaudible at 128 kbps and above. If the recording is music or you want headroom, pick 192 kbps.