Convert webm to opus
Converted on your device. Files never leave this tab. Output tops out around 2 GB.
Nothing is uploaded
The converter runs inside this page. Cut your network after it loads and it still works.
No account, no daily limit
No sign-up, no daily limit, no watermark, no queue behind other people's files. Batch as many WEBM files as you like.
Real OPUS output
Encoded by ffmpeg, the same library the command-line tools use — not a renamed extension.
About WEBM
WebM
An open container from Google, launched in 2010 and based on Matroska, holding VP8, VP9 or AV1 video with Vorbis or Opus audio. Convert from WebM to MP4 for editors, phones and apps that handle MP4 better.
About OPUS
Opus
An open, royalty-free lossy codec standardized by the IETF as RFC 6716 in 2012, built for speech and music at low bitrates. WebRTC calls and WhatsApp voice notes use it, usually inside an Ogg container. Use it for the smallest files at good quality for voice, podcasts or music, when the player supports it.