About MP4 to MKV
MP4 to MKV is a free online converter that turns MP4 files (most-compatible video) into MKV files (Matroska container). Upload your file, click convert, and download the result — no signup, no software install, nothing to learn.
Whether you need to share a MKV with a teammate, embed it in a website, or open it in a different app, our converter handles the format change cleanly while preserving as much of the original quality as the target format allows.
All processing happens on our secure servers using industry-standard tools (ffmpeg, ImageMagick, Ghostscript). Files are encrypted in transit with TLS and auto-deleted within 1 hour, so your data stays yours.
Privacy first: Your files are processed using client-side JavaScript when possible. Files sent to our servers are encrypted with TLS and automatically deleted within 1 hour.
How to use MP4 to MKV
Get the result you need in just three simple steps:
Upload your MP4 file
Drag and drop your MP4 file into the upload zone, or click to browse from your device. Files up to 512 MB are supported.
Click "Run MP4 to MKV"
Our converter runs the format change server-side. Small files complete in seconds; larger files run in the background and notify you when ready.
Download your MKV
Once the conversion finishes, your MKV file downloads automatically. The file is then removed from our servers within 1 hour.
Key Features
Fast MP4 → MKV conversion
Tuned codec settings and modern compression deliver quick conversions even on multi-megabyte files, without sacrificing the quality you'd expect from a paid app.
No watermarks, no signup
The output is yours, clean. No watermarks added, no account required, no daily limits beyond a generous 512 MB per file.
Privacy-first pipeline
Uploads use TLS, files are isolated per session, and everything is deleted automatically within 60 minutes of upload.
Cross-platform
Because the conversion runs on our servers, it works the same on Windows, macOS, Linux, iOS, and Android — no app to install.
Common Use Cases
- Convert MP4 files for sharing with people whose software doesn't open the original format
- Re-encode MP4 into MKV for embedding in a website, slide deck, or app that only accepts MKV
- Archive content in MKV format for long-term compatibility
- Prepare files for a platform that requires MKV uploads
- Reduce file size or change compatibility by switching from MP4 to MKV
Security & Privacy
We take your data security seriously. Here's how we protect your files:
- TLS encryption: All file transfers are encrypted using industry-standard TLS 1.3 protocol.
- Auto-deletion: Uploaded files are automatically and permanently deleted from our servers within 1 hour.
- No access: We never read, analyze, or store the contents of your files.
- Browser processing: When possible, files are processed directly in your browser without being uploaded.