Free Online MP4 to MKV Converter
Instantly convert your MP4 videos to MKV format. 100% free, secure, and works on any device.
Upload MP4 File
Select a single file
Max size: 200MB
How to convert MP4 to MKV online
Follow these three simple steps to convert your files.
Upload MP4
Select the MP4 videos you wish to convert from your computer or phone.
Convert to MKV
Hit the convert button and let our advanced engine transform it to MKV.
Download File
Save the resulting MKV file. Your original file is safely deleted from our servers.
Why convert MP4 to MKV?
If you need to open a MP4 file but your device only supports MKV, you're in the right place. Converting MP4 to MKV solves format incompatibility issues instantly. Plus, our cloud-based system means you don't need to install any heavy software.
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Secure Conversions
"Honestly the fastest converter I've ever used. No ads, no BS, it just works perfectly every single time."
Sarah Jenkins
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"I use this daily to convert massive 4K video files for my podcast. The fact that it's free and handles 200MB+ files is insane."
Marcus Chen
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