Convert AVI files to MKV free in your browser — no signup, no install, and the file is never uploaded to a server. MKV compresses further, so the file gets noticeably smaller.
Add your AVI file
Drag the AVI file onto the drop area above, or click it to pick a file from your device. You can add several files at once.
Confirm MKV as the output
MKV is already selected as the output format on this page. You can pick the resolution. Encoding is the slowest part, so smaller resolutions finish sooner.
Run the conversion
Press the convert button. Video is re-encoded frame by frame on your own machine, so a long clip can take several minutes. The tab has to stay open.
Download the MKV file
When it finishes, download the MKV file. Converting multiple files gives you the option to download them together as a ZIP.
An old video container created by Microsoft in 1992. Compatibility is broad, but support for modern codecs and subtitles is limited.
An open-source video container able to hold unlimited subtitles, audio tracks, and chapters. It is favored for archiving high-quality video.
Yes. AVI to MKV conversion is completely free with no signup, no watermark, and no daily limit on the free plan for ordinary use.
No. The conversion runs entirely inside your browser using WebAssembly, so the AVI file never leaves your device. That is also why it works without an internet connection once the page has loaded.
MKV uses lossy compression, so some detail is discarded. At high quality settings the difference is usually invisible, and the file becomes far smaller.
The free plan handles files up to 200MB. Because processing happens on your own device, very large files depend on your computer's memory rather than a server quota.
Video converter
What each file format is, what it is used for, and which formats it can be converted to.
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