Convert MP4 to MKV Online Free
Runs 100% in your browser — your files never leave your device.
MKV is the collector's container: flexible, metadata-friendly, and loved by media servers like Plex and Jellyfin. Convert an MP4 into MKV without uploading for typical sizes — bigger files process on our servers and are auto-deleted within an hour.
How it works
- 1
Add your file
Drop your file in or click to browse. Small files never leave your device.
- 2
Convert
Large files automatically finish on our servers instead and are deleted within an hour.
- 3
Download
Save the result instantly — original quality preserved as much as the format allows.
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