Convert mkv 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 MKV files as you like.
Real OPUS output
Encoded by ffmpeg, the same library the command-line tools use — not a renamed extension.
About MKV
Matroska Video
An open container first released in 2002 that can hold almost any video and audio codec, plus several audio tracks, subtitle tracks and chapters in one file. Use it to keep multiple languages and subtitles together; convert to MP4 for devices that do not read MKV.
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.