Convert your MP4 files to MKV instantly online. Free, fast, and secure — no signup required.
Convert MP4 to MKV Free →No software to install. Works in your browser on any device.
Click "Choose File" or drag and drop your MP4 file onto the converter. Up to 50 MB free.
FlipFiles will detect your file type automatically. Click the .MKV format button to select it.
Hit Convert and download your MKV file in seconds. No watermarks, no registration needed.
Understanding your file formats helps you choose the right conversion.
The world's most compatible video format. Plays on every device, browser, and media player without plugins.
A flexible open container that can hold multiple audio tracks, subtitles, and video in one file.
Everything you need to know about converting MP4 to MKV.
Yes, completely free. You get 3 free conversions per session with no account required. Create a free account to save your history, or upgrade for unlimited conversions.
Most MP4 to MKV conversions complete in under 10 seconds. Larger files may take slightly longer depending on your internet connection and file size.
Yes. All uploaded files are processed on our secure servers and automatically deleted within 10 minutes of conversion. We never store or share your files.
Quality depends on the output settings. FlipFiles uses optimized defaults to preserve the best quality for MKV files.
Yes! FlipFiles works in any browser on mobile, tablet, or desktop. No app download required.
Join thousands of users who convert files with FlipFiles every day. No account needed to get started.
Start Converting →Need a different format? We've got you covered.