A quick guide to the most common video container formats - what they are, what they're used for, and how they compare.
The universal standard. MP4 is supported on every device, browser, and platform. It's the right choice for sharing, uploading, or distributing video almost anywhere. If you're not sure which format to use, use MP4.
Apple's QuickTime format, and the default recording format on iPhones and many digital cameras. MOV files are high quality and work great within Apple's ecosystem, but can cause compatibility issues on Windows or Android. Converting MOV to MP4 is one of the most common video conversions.
An open-source format popular for high-definition video archives and home media servers. MKV can hold multiple audio tracks, subtitle tracks, and chapters in a single file - more flexible than MP4, but with narrower device support. Common in Plex and Jellyfin libraries.
Microsoft's older video format from 1992, still encountered when working with footage from early digital cameras or archived content from the 2000s. AVI files are often large and less compatible with modern platforms. Converting to MP4 is usually the right move.
An open-source format built for the web, developed by Google. WebM is royalty-free and plays natively in all major browsers, making it a good choice for embedding video on websites. Outside the browser, compatibility is limited - MP4 is more practical for general use.
You can convert MOV to MP4 - or convert between any of the formats above - directly in your browser. No software to install, no upload required.