Convert MKV to MP4 Online – Free and Fast
MKV to MP4 Converter – Free Online, No Quality Loss
MKV files don't play on every device or platform. This tool converts them to MP4 — the most widely supported video format — without re-encoding, so the quality stays the same. Upload your MKV, convert, and download the MP4. No software to install, works in your browser.
How it works
Upload the MKV
Choose the video you need as a more compatible MP4.
Convert the container
Video, audio, and supported tracks are prepared for MP4 playback.
Download and test
Check audio track, subtitles, and playback on the device you care about.
Frequently asked questions
About MKV to MP4
MKV to MP4 helps when a video plays in desktop players but fails on a phone, TV, browser, editor, or upload platform. MKV can hold many audio tracks, subtitles, and advanced features, while MP4 is more broadly accepted. If the video codec is already compatible, conversion may only need to change the container. If not, the video may be re-encoded. Subtitles and extra audio tracks can behave differently because MP4 does not support every MKV feature the same way. Check the output for the correct audio language, subtitle behavior, and playback on the target device.
Updated June 2026: Added guidance for MKV to MP4 conversion, container differences, subtitles, audio tracks, streaming devices, and compatibility.
Also try these tools
MP4 to MP3
MP4 to MP3 Converter – Extract Audio Free Online
MP4 to GIF
Convert MP4 files to GIF online
MOV to MP4
MOV to MP4 Converter – Free Online, Keep Quality
AVI to MP4
AVI to MP4 Converter – Free Online, No Quality Loss
WEBM to MP4
WebM to MP4 Converter — Free Online | f2file
MP4 to WEBM
Convert MP4 files to WEBM online