WMV to MKV Converter — Free, Online, No Upload

WMV is a closed, proprietary format that requires Windows Media codecs to decode — codecs that are not available on Linux, are absent from most open-source tools, and are increasingly dropped from modern software. If you run Plex, Jellyfin, Kodi, or any Linux-based media server, WMV files are second-class citizens that may not transcode cleanly or may force your server to work harder than necessary.

MKV (Matroska) is the container format that open-source media servers were built around. Plex, Jellyfin, Kodi, and VLC all treat MKV as a first-class format. MKV supports multiple audio tracks, subtitle streams, chapter markers, and HDR metadata — capabilities that WMV lacks entirely. It is the standard container for Blu-ray rips and high-quality digital media collections.

Converting WMV to MKV gives your video a future-proof container that integrates cleanly with your media server. The video and audio are re-encoded to open codecs — typically H.264 or H.265 for video and AAC for audio — which any media server can handle without transcoding overhead. The resulting MKV file is better indexed, more compatible, and better supported than WMV across every modern media platform. File sizes may be smaller than the original WMV at equivalent quality, depending on the codec used.

Typical sizes: WMV 50–150 MB (1 minute 720p); MKV 200–800 MB (1 minute 1080p).