PRIVATE BROWSER PROCESSING
Convert MKV to MP4 for easier playback and sharing
MKV is excellent at holding different streams, but it is not always the easiest file to hand to a phone, browser, editor, or social platform. Convert the main video and audio to MP4 here.
MKV to MP4
MKV is flexible; MP4 is usually easier to hand off
An MKV can contain several audio tracks, subtitles and attachments. This tool converts the main video stream and first audio stream into MP4 rather than preserving every MKV track.
Privacy and limitations
Processing uses FFmpeg WebAssembly locally. The video is not uploaded by this tool. Closing or refreshing the page clears the working file. Speed depends on the browser, device memory, source codec, duration, and resolution, and tools that re-encode are not lossless.
Common questions
Can I just rename the file extension?
Usually not. Renaming does not change the container or codecs inside; this page performs a real conversion.
Is my video uploaded to DJAI?
No. The source file is read and processed in your browser on your device.
Why can the first run take longer?
The browser downloads an FFmpeg WebAssembly core of roughly 31 MB the first time processing is needed; caching can help later runs.
BUILD WITH DJAI
Want to build a tool like this one?
This tool runs entirely in the browser. Explore DJAI Academy’s practical building courses.