Convert MP4 to MKV
Free and instant — your MP4 files are processed securely on our servers and deleted right after conversion. Nothing is stored.
How to convert MP4 to MKV
- Step 01
Add your MP4 files
Drop them into the box above or click to browse. You can add several files at once.
- Step 02
Conversion starts instantly
Your file is sent to our servers, converted and deleted right away — no sign-up, no queue, no waiting.
- Step 03
Download your MKV files
Save each file individually or grab them all at once. Done.
Why convert MP4 to MKV?
Building a media library for Plex, Jellyfin or another home server? Converting to MKV gives you a flexible open container that can hold multiple audio tracks and subtitles alongside your video.
MP4 vs MKV at a glance
MP4 is the universal video format — plays on every device, browser and platform without extra codecs. MKV is the flexible open container — can hold almost any codec, multiple audio tracks and embedded subtitles, but browser support is limited.
| Property | MP4 | MKV |
|---|---|---|
| Extension | .mp4 | .mkv |
| Full name | MPEG-4 Part 14 | Matroska Video |
| First released | 2001 | 2002 |
| Developed by | ISO/IEC JTC 1 | Matroska project |
| Compression | Lossy | Lossy |
| Transparency | No | No |
| Animation | No | No |
| Best for | video sharing, streaming and playback on any device | high-quality video with multiple audio tracks and subtitles |
MP4 to MKV — frequently asked questions
Is this MP4 to MKV converter really free?
Yes — completely free, with no sign-up, no watermarks and no daily limits.
Will I lose quality converting to MKV?
MKV uses lossy compression, so the image is re-encoded at high quality (92%). For photos the difference is practically invisible; for text-heavy graphics or logos, a lossless format like PNG preserves sharp edges better.
Is the conversion private?
Video conversion runs on our servers with ffmpeg — your file is deleted immediately and never stored.
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