Convert FLV files to MKV free in your browser — no signup, no install, and the file is never uploaded to a server.
Add your FLV file
Drag the FLV 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.
The web video format of the Adobe Flash era. With Flash fully discontinued, playback options have disappeared, making conversion essentially mandatory.
An open-source video container able to hold unlimited subtitles, audio tracks, and chapters. It is favored for archiving high-quality video.
Yes. FLV 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 FLV file never leaves your device. That is also why it works without an internet connection once the page has loaded.
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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