Container Formats Explained: MP4, MKV, WebM, and MOV
Container formats wrap video, audio, and metadata into a single file. Understanding the difference between MP4, MKV, WebM, and MOV helps you choose the right wrapper for your video content.
Key Takeaways
- A common source of confusion is the difference between codecs and containers.
- MP4 is the most widely supported container format.
- Matroska (MKV) supports virtually every codec and feature: multiple audio tracks, subtitle tracks, chapters, attachments, and metadata.
- WebM is Google's container for VP8, VP9, and AV1 codecs.
- QuickTime MOV is Apple's container format.
Resolution Reference
Codec vs Container
A common source of confusion is the difference between codecs and containers. The codec determines how video is compressed; the container determines how the compressed data is packaged.
Think of it like a shipping box (container) holding various items (codec streams, subtitles, metadata). The same item can go in different boxes.
MP4 (.mp4): Universal Container
MP4 is the most widely supported container format. It supports H.264, H.265, AAC, and many other codecs. It's the default for web video, social media, and mobile devices.
Supports: H.264, H.265, AAC, subtitles (limited).
MKV (.mkv): The Kitchen Sink
Matroska (MKV) supports virtually every codec and feature: multiple audio tracks, subtitle tracks, chapters, attachments, and metadata. It's popular for media libraries.
Supports: Everything — H.264, H.265, AV1, VP9, FLAC, DTS, chapters.
WebM (.webm): Web-Optimized
WebM is Google's container for VP8, VP9, and AV1 codecs. It's designed for web delivery and is supported natively in all modern browsers.
Supports: VP8, VP9, AV1, Vorbis, Opus.
MOV (.mov): Apple's Container
QuickTime MOV is Apple's container format. It's functionally similar to MP4 but has better support for ProRes and Apple-specific codecs.
Supports: H.264, H.265, ProRes, AAC, PCM.
Choosing the Right Container
| Use Case | Recommended Container |
|---|---|
| Web delivery | MP4 or WebM |
| Media archive | MKV |
| Apple ecosystem | MOV |
| Social media upload | MP4 |
| Professional editing | MOV (ProRes) |
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