Two tools, both running entirely in your browser — nothing is uploaded. Play a Matroska file, or crack one open and inspect its structure byte by byte.
Paste a video URL or pick a local .mkv and it just plays — remuxed to fragmented MP4 on the fly, with switchable audio tracks and ASS/SSA subtitles rendered by libass. The full player, no signup, nothing uploaded. This is the same engine that powers the Nextcloud app and the embeddable player.
Drop an .mkv or .webm and explore its EBML structure as a collapsible tree — every element with its ID, size, and raw bytes in a hex inspector — plus a quick summary of tracks, codecs, languages, resolution, and duration. Handy for debugging files or learning the container format.
Want this in your own product? Get in touch about the engine or the player.