: Use a reliable antivirus to check the file. Double extensions are a classic trick to hide the true nature of a file (e.g., an executable .exe masked as a video).

: Another free utility where you can drag the file in and select an output profile like "HTML 5 MP4" for broad compatibility. 4. Background on Openload

: A user-friendly option for converting MKV to MP4 on Windows or Mac. Simply load the file, choose "MP4 H.264," and click Run.

: This is the most versatile option for playing MKV and MP4 files without needing extra codec packs.