Convert MKV to OPUS
Extract the audio from your MKV video files and save it as OPUS, directly in your browser.
How to convert video to audio in 3 steps
Choose a MKV video file.
Click convert to OPUS.
Download your OPUS audio.
Format descriptions
MKV — MKV (Matroska) is a flexible open-source video container that supports multiple video, audio and subtitle tracks in a single file.
OPUS — OPUS is a modern, open and royalty-free audio codec. It delivers excellent quality even at low bitrates, making it ideal for streaming, voice and podcasts.
Technical comparison: MKV vs OPUS
Technical breakdown of the MKV and OPUS specifications: compression, colour, transparency and animation support.
| Property | MKV | Opus |
|---|---|---|
| Specification | MKV (Matroska Multimedia Container) | Opus (Opus Interactive Audio Codec) |
| Media type | Video | Audio |
| Compression | Hybrid (lossy or lossless) · H.264 / HEVC / VP9 / AV1 | Lossy · Opus (RFC 6716) |
| Color space / bit depth | 8/10/12-bit HDR | 16-bit, 8-48 kHz |
| Transparency | Not applicable | Not applicable |
| Animation | Yes (animated) | No (static) |
| Best for | MKV (Matroska) is a flexible open-source video container that supports multiple video, audio and subtitle tracks in a single file. | OPUS is a modern, open and royalty-free audio codec. It delivers excellent quality even at low bitrates, making it ideal for streaming, voice and podcasts. |
What happens when converting MKV to OPUS?
The MKV data is decoded inside your browser with WebAssembly and re-encoded to the OPUS specification, so no file is ever uploaded to a server. OPUS uses lossy compression: the file gets far lighter, but a small amount of fine detail is discarded in the process. MKV supports animation while OPUS does not, so only the first frame is kept. Audio is re-encoded with the OPUS codec while keeping the original duration, so audio and video stay in sync.
Frequently Asked Questions
What is video to audio conversion?
Video to audio conversion extracts the sound track from a video file, for example from MKV to OPUS, keeping only the audio content.
Are my video files uploaded?
No. This tool processes video files directly in your browser. Your video files are never sent to a server.
Which video formats are supported?
This tool converts the audio of MKV video files to OPUS, all in your browser.
Is it really free and unlimited?
Yes, the tool is completely free and you can convert as many videos as you want, with no limits.
Does it work on mobile too?
Yes, it works on any modern device, including smartphones, tablets and desktop computers.
Which format will the result be in?
The converted file will always be in OPUS format, ready to download and use.
About the video to audio converter
Extract and convert the audio from your MKV videos to OPUS for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
See also:
- Video to Audio Converters
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- Convert MKV to MP3Extract and convert the audio from your MKV videos to MP3 for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
- Convert MKV to WAVExtract and convert the audio from your MKV videos to WAV for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.
- Convert MKV to OGGExtract and convert the audio from your MKV videos to OGG for free. Everything happens in your browser: your files are never uploaded to a server, and you need no downloads or sign-up to get started.