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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

  1. 1Upload your MP4 video
  2. 2Conversion runs instantly
  3. 3Download your MKV file

Drop your video anywhere, click to browse

MP4, MOV, AVI, MKV, WebM, FLV, WMV, VOB

Ctrl+Vto paste a copied file

How to use MP4 to MKV

  1. 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. 2

    Conversion runs instantly

    ToolBubble converts the video to MKV directly in your browser — no waiting in an upload queue.

  3. 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.

MKV (Matroska) supports multiple audio languages, multiple subtitle tracks, chapter markers, and theoretically unlimited file size. It is the preferred format for home media servers (Plex, Jellyfin, Kodi) and high-quality video archiving.

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