MP4 to MKV
Convert MP4 videos to MKV (Matroska) format for archiving and media server use. MKV supports multiple audio tracks, subtitle streams, chapter markers, and large file sizes — making it ideal for home media library management with Plex, Jellyfin, or Kodi. No signup.
Updated June 2026
- 1Upload your MP4 video
- 2Conversion runs instantly
- 3Download your MKV file
Drop your video anywhere, click to browse
MP4, MOV, AVI, MKV, WebM, FLV, WMV, VOB
How to Use MP4 to MKV
- 1
Upload your MP4 video
Drag and drop your MP4 file into the upload area, or click to browse and select it from your device. Nothing is sent to a server.
- 2
Conversion runs instantly
ToolBubble converts the video to MKV directly in your browser — no waiting in an upload queue.
- 3
Download your MKV file
Once processing finishes, the converted MKV file downloads automatically to your device.
Frequently Asked Questions
Why use MKV instead of MP4?▼
Is there any quality loss converting MP4 to MKV?▼
Does Plex or Jellyfin prefer MKV over MP4?▼
Can I add subtitles to the MKV output?▼
Is the conversion done in the browser?▼
How to use MP4 to MKV
- 1
Upload your MP4 video
Drag and drop your MP4 file into the upload area, or click to browse and select it from your device. Nothing is sent to a server.
- 2
Conversion runs instantly
ToolBubble converts the video to MKV directly in your browser — no waiting in an upload queue.
- 3
Download your MKV file
Once processing finishes, the converted MKV file downloads automatically to your device.
Frequently asked questions
Everything you need to know about mp4 to mkv.
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