Quick definition
MKV is a flexible video container that can hold video, audio, subtitle, and chapter tracks in one file.
Best use cases
Archival videos, subtitle-heavy media, high-quality source files, and multi-track playback.
What to watch out for
Some smart TVs, phones, browsers, and upload portals prefer MP4 and may reject MKV files.
Related converters
Conversion tip
Keep the original file, create a converted copy, then compare file size, quality, and compatibility before deleting or uploading the result.