Convert MKV to MP4 Online
Free, private MKV to MP4 converter. Your files never leave your browser. All processing happens locally on your device.
Drag & drop files here
images, PDFs, documents, audio, video, and more
No Server Uploads
FormatShift converts files directly in your browser. Your files never leave your device, so there's nothing to intercept or leak.
Instant Export
Files convert on your machine, so downloads are ready right away, even on slow connections.
High Fidelity
Good encoding keeps your files looking and sounding right, even at smaller sizes.
Built for Privacy
Your files are processed entirely in your browser. They never leave your device.
How to convert MKV to MP4
Drop your MKV file
Drag your file onto the converter above, or click to browse your files. Your files stay on your device.
Automatic conversion
FormatShift converts your file right in your browser using WebAssembly. No server involved, so your data stays completely private.
Download your MP4 file
Once the conversion finishes, click the download button and you are done. The converted file is ready to use.
Why convert MKV to MP4?
MKV and MP4 serve different purposes. Converting between them lets you use whichever format works best for your situation.
What is a MKV file?
Matroska Video: MKV is a flexible, open-source video container popular for high-definition movies and TV shows. It can hold multiple audio tracks, subtitles, and chapters in a single file, which is why movie rips often use it.
Created by: Matroska team, first released in 2002
Used for: HD movie files, TV show collections, videos with multiple audio/subtitle tracks
Technical details: Open container format supporting virtually any video and audio codec. Supports multiple audio tracks, subtitle streams, chapter markers, and metadata.
Compatibility: Supported by VLC, most desktop media players, and some smart TVs. Not natively supported by web browsers or many mobile players.
What is a MP4 file?
MPEG-4 Part 14: MP4 is the most widely used video format. Phone recordings, YouTube downloads, streaming services, social media, almost everything uses MP4. It supports video, audio, and subtitles in a single file.
Created by: Moving Picture Experts Group (ISO/IEC), standardized in 2001
Used for: Video streaming, social media, phone recordings, web video, TV shows and movies
Technical details: Container format supporting H.264/H.265 video, AAC audio, and subtitle tracks. Lossy compression provides good quality at manageable file sizes.
Compatibility: Plays on virtually every device, browser, and operating system without extra software.
MKV vs MP4
| Feature | MKV | MP4 |
|---|---|---|
| Type | Matroska Video | MPEG-4 Part 14 |
| Best for | HD movie files, TV show collections, videos with multiple audio/subtitle tracks | Video streaming, social media, phone recordings, web video, TV shows and movies |
| Compatibility | Supported by VLC, most desktop media players, and some smart TVs. Not natively supported by web browsers or many mobile players. | Plays on virtually every device, browser, and operating system without extra software. |
| Pros | Extremely flexible, supports multiple streams, open format | Universal compatibility, good compression, supports multiple streams |
| Cons | Not supported by browsers, less compatible than MP4 for sharing | Lossy compression means some quality loss, editing requires re-encoding |