Convert MOV to MKV Online
Convert your QuickTime MOV files to Matroska MKV — lossless remux, in your browser.
.mov · up to 100 MB
What you can do
MOV to MKV: the universal format for media servers
Plex and Kodi native
MKV is the preferred format for Plex and Kodi direct play without real-time transcoding.
Unlimited subtitles
Add SRT, ASS, or SSA subtitle tracks to your MKV with MKVToolNix after conversion.
No re-encoding
Video and audio from the MOV are copied intact into the MKV container. Identical quality.
100% private
Your video is processed in your browser. Never uploaded to any external server.
How it works
Three steps, no hassle
Upload your MOV file
Drag or select your .mov file exported from Final Cut Pro, iMovie, or QuickTime. Up to 2 GB.
Remux to MKV
Video, audio, and subtitle tracks are transferred to the Matroska container with no re-encoding. Identical quality.
Download your MKV
File ready for Plex, Kodi, VLC, Jellyfin, or any Matroska-compatible player.
FAQ
Got questions?
MOV (QuickTime File Format, specified by Apple in 1991) and MKV (Matroska, developed by Steve Lhomme and Moritz Bunkus from 2002) are both multimedia containers, but with very different design philosophies. MOV uses the ISOBMFF (ISO Base Media File Format, ISO 14496-12) architecture, built on nested atoms/boxes — the same foundation as MP4. MKV uses EBML (Extensible Binary Meta Language, RFC 8794), a self-describing binary format inspired by XML where every element carries an explicit ID and size. EBML allows new elements to be added without breaking existing players, and facilitates recovery from corrupted files. The most important practical difference: MKV supports an unlimited number of subtitle tracks, chapters with metadata, per-track tags, and file attachments (e.g., fonts). MOV supports these partially, with limited interoperability outside Apple players.
Not natively. Final Cut Pro X (renamed Final Cut Pro in 2021) exports primarily to MOV (ProRes, H.264, H.265/HEVC), MP4, MXF, and FCPXML. MKV is not a native export format in any Apple tool. The standard workflow for media server distribution on Plex or Jellyfin is: export to MOV from Final Cut Pro with the desired codec → convert the MOV container to MKV with this tool (lossless remux) → optionally add SRT subtitle tracks or additional audio tracks to the MKV using MKVToolNix.
MKV is the preferred format for both Plex Media Server and Kodi (formerly XBMC, started in 2002). Both platforms read MKV containers with H.264, H.265/HEVC, VP9, and AV1 directly, and take full advantage of embedded multi-language audio and subtitle tracks. Plex in particular recommends MKV to minimize real-time transcoding: if the client device can decode the MKV codec natively, Plex does direct play, reducing server CPU load to near zero. Final Cut Pro MOVs with ProRes require transcoding in Plex because Android, Roku, and Fire TV Plex clients don't support ProRes; an MKV with the H.264 stream from the same MOV plays without transcoding.
Technical track metadata (sample rate, resolution, frame rate, color space) is fully preserved in the remux. Container-level metadata such as title, author, and creation date is transferred where available. Apple-proprietary metadata (QuickTime fields like 'com.apple.quicktime.camera.identifier' or GPS location data saved by iMovie) may have no direct equivalent in Matroska tag specifications and may be dropped or approximated. For media server distribution this is irrelevant; for forensic archival of original metadata, keep the source MOV.
Yes, and this is one of MKV's main advantages over MOV. MKVToolNix (free cross-platform tool by Moritz Bunkus, available at mkvtoolnix.download since 2003) lets you add .srt, .ass, .ssa, or .sub files to an MKV without re-encoding video. The command is: mkvmerge -o output.mkv input.mkv --language 0:eng subtitles.eng.srt --language 1:spa subtitles.spa.srt. This produces a new MKV with all original tracks plus subtitle tracks selectable by the user at playback. MOV supports 'tx3g' (plain text) subtitles but not SSA/ASS, and player compatibility outside Apple is limited.
iPhones since the iPhone 7 (2016) can record in HEVC/H.265 with Main 10 profile at 4K 60fps. These MOVs contain HEVC streams in a QuickTime container. Remuxing to MKV is fully valid: HEVC is perfectly supported in Matroska (codec ID V_MPEGH/ISO/HEVC per the Matroska specification). The advantage is that MKV with HEVC is directly compatible with Plex, Kodi, VLC, and Jellyfin, while HEVC MOV may require additional plugins on Windows players. Dolby Vision video recorded by iPhone 12 and later uses HDR10 compatibility layer metadata that is preserved in the remux.
Convert MOV to MKV: QuickTime to Matroska for Plex, Kodi, and VLC
MOV (QuickTime File Format) was developed by Apple and introduced in 1991 alongside QuickTime 1.0, the first real-time digital video system for consumer personal computers. The format's architecture is based on atoms (called 'boxes' in the derived ISO 14496-12 specification): nested data containers where each atom has a 4-byte size, a 4-byte type (FourCC), and variable-length data. This hierarchical structure is the same foundation on which MP4 was built when MPEG standardized the format in ISO 14496-12 in 2001. MOV was for years the reference format for professional video production in the Apple ecosystem: Final Cut Pro, Motion, and Compressor generate MOV by default, and ProRes codecs (Apple ProRes 422, ProRes 4444, ProRes RAW — introduced between 2007 and 2018) are only natively available in MOV and MXF containers. However, MOV's dominance in production contrasts with its limited compatibility in playback outside the Apple ecosystem: players on Windows, Android, and network devices (Synology, QNAP NAS) frequently struggle with MOV, especially with ProRes codecs that require licensing.
Matroska (MKV) was conceived in 2002 by Steve Lhomme and Moritz Bunkus as a completely open multimedia container, free of patent restrictions, designed specifically to overcome AVI's limitations (2 GB file size cap, no embedded subtitle support) and improve on MOV and MP4 interoperability. Matroska's foundational technical decision was to base its format on EBML (Extensible Binary Meta Language), a self-describing binary encoding scheme where each element carries its own ID and length, conceptually similar to XML but optimized for efficient binary parsing. This choice has important consequences: MKV files are resilient to partial corruption (if one segment is corrupted, the player can resume from the next SeekHead), extensible without breaking existing players, and the specification has been fully public from the start at matroska.org. WebM, Google's web video format announced in May 2010 alongside the VP8 codec, is technically a restricted subset of Matroska: a valid WebM file is also a valid MKV file, but with codec IDs limited to VP8/VP9/AV1 for video and Vorbis/Opus for audio.
Convertir.ai runs MOV to MKV conversion in the browser using FFmpeg.wasm, without sending video to external servers. The remux process analyzes the QuickTime MOV container by reading the 'moov' atom (which contains the full track index in 'trak' → 'mdia' → 'minf' → 'stbl' substructures), extracts per-track information (codec type by FourCC, timestamps in the MOV container time system defaulting to 90 kHz, sample offsets in 'stco'/'co64'), and reconstructs the Matroska EBML equivalent: the EBML Header block with version and DocType 'matroska', the Segment element with SeekHead for fast navigation, the Info block with timestamps and title, and individual TrackEntry elements for video and audio with Matroska codec IDs (V_MPEG4/ISO/AVC for H.264, V_MPEGH/ISO/HEVC for HEVC, A_AAC for AAC, A_AC3 for Dolby). The compressed bytes of each track are copied directly from MOV data blocks to Matroska SimpleBlocks or BlockGroups without any decoding, preserving original quality with perfect fidelity.