Convert GIF to MKV Online
Convert animated GIFs to MKV for Plex, Kodi, and media libraries, free, in your browser.
.gif · up to 100 MB
What it's for
GIF to MKV: animations for your Plex and Kodi library
Native Plex and Kodi
H.264 MKV plays directly without transcoding in Plex, Kodi, and Jellyfin.
Full metadata
MKV supports standard XML tags to organize meme collections with title, date, and description.
Embedded subtitles
Add SRT/ASS tracks to the MKV with MKVToolNix without re-encoding the video.
100% private
Conversion runs in your browser with FFmpeg.wasm. Your GIFs never leave your device.
How it works
Three steps, no hassle
Upload your animated GIF
Drag or select your .gif file. Up to 50 MB, no signup.
Conversion to MKV with H.264
FFmpeg processes the GIF in your browser and outputs an H.264 MKV file. No server uploads.
Add to your media library
The MKV integrates directly into Plex, Kodi, Jellyfin, or any compatible media player.
FAQ
Got questions?
MKV (Matroska Video, publicly specified since 2002) is an open-source container supporting an unlimited number of video, audio, and subtitle tracks, while MP4 has stricter codec and metadata constraints. For Plex or Kodi libraries, MKV is the preferred format because it allows embedding ASS/SSA subtitle tracks (used in anime and fansubs), multiple audio tracks, and chapters — all in a single file. For meme or visual-reference animation collections, MKV allows adding standard metadata tags (title, year, description) that Plex and Kodi read to automatically organize the library.
Yes. Plex Media Server has natively supported MKV with H.264 since version 0.9.x (2012). Plex clients on Roku, Apple TV, Android TV, Fire TV, and web browsers play MKV with H.264 without server-side transcoding when the H.264 profile is Main or High up to level 4.1, meaning direct play with zero server CPU usage. For older devices that don't support H.264 High level 4.1, Plex will transcode automatically. The MKV generated by Convertir.ai uses H.264 Main profile, compatible with the widest range of Plex devices.
Yes. MKV is the most convenient format for externally adding subtitles. With MKVToolNix (free, open-source tool for Windows, macOS, and Linux), you can mux an SRT, ASS, SSA, or PGS subtitle file into the existing MKV without re-encoding the video. In Kodi, if you place an .srt file with the same name as the .mkv in the same folder, Kodi loads it automatically. This is especially useful for multilingual collection organization or for educators who want to add transcriptions to explanatory animations.
For a collection of GIF memes converted to video, practical differences are: MKV supports standard XML metadata tags (MKV Tags Specification) including TITLE, DATE_RECORDED, DESCRIPTION, and KEYWORDS fields — useful for search in Plex libraries. MP4 uses iTunes-style metadata with more limited fields. MKV has no built-in digital rights management (DRM), while MP4 containers can carry Widevine or FairPlay DRM. MKV is the de facto standard for high-quality internet content distribution (the majority of anime and fansub downloads have used MKV since 2005).
It depends on the manufacturer. Samsung (Tizen OS), LG (webOS), and Sony (Android TV/Google TV) Smart TVs have natively supported MKV with H.264 playback since their 2015–2016 models. Older TVs with USB connectivity may play MKV via USB if their firmware includes the H.264 codec. For maximum compatibility with unknown TVs, MP4 remains the safest choice. Amazon Fire Stick, Apple TV 4K, Chromecast with Google TV, and PlayStation/Xbox consoles all support MKV with H.264 without issues.
H.264 in Main or High profile (standard profiles for general compatibility) does not support an alpha channel. GIF transparency — one color from the 256-color palette designated as transparent via the Transparent Color Flag in the GCE block — is filled with a black background in the resulting MKV. If you need to preserve transparency in video, the correct format would be WebM with VP9 codec (which supports an alpha channel), though media player compatibility is more limited than H.264/MKV.
Convert GIF to MKV: animations for Plex, Kodi, and multimedia collections
The Matroska (MKV) format was conceived in 2002 by Steve Lhomme as an open-source multimedia container free of licensing restrictions, in contrast to AVI (Microsoft-proprietary) and MOV (Apple-proprietary). The Matroska specification is based on EBML (Extensible Binary Meta Language), a binary encoding similar to XML that allows indefinite extensibility without breaking forward compatibility. MKV became the dominant container for high-quality internet content distribution: the anime fansub community adopted MKV around 2005 for its native ASS/SSA subtitle support, and today roughly 80% of multimedia content downloads on Usenet and BitTorrent trackers use MKV. Plex Media Server, with over 20 million active users, recognizes it as one of the three primary formats alongside MP4 and AVI.
Converting GIF to MKV makes specific sense for organized multimedia collection management. Animated GIFs have been the standard meme format since roughly 2012, when platforms like Tumblr, Reddit, and 4chan popularized them massively. A user with a collection of hundreds or thousands of GIFs faces an organization problem: GIFs don't support standard metadata beyond the GIF89a comment field, don't appear correctly in Plex or Kodi, and their file size is disproportionately large compared to equivalent video content. Converting to MKV solves all these problems: H.264 in MKV reduces file size by 5 to 20 times, MKV tags allow adding title, year, genres, and descriptions that Plex uses for its library interface, and Kodi can organize the collection with automatic cover art and synopses when standard file naming conventions are used. For reference animation collections — reactions, TV show clips, educational animations — MKV with metadata is significantly superior to the original GIF as a long-term archival format.
Convertir.ai performs the GIF-to-MKV conversion in the browser using FFmpeg.wasm, the WebAssembly build of FFmpeg (a project started by Fabrice Bellard in 2000, now maintained by the FFmpeg community). The technical process involves: frame-by-frame GIF decoding with libavcodec's gif decoder, respecting delays from the Graphic Control Extension block; conversion of each frame from the 256-color palette to YCbCr 4:2:0 color space; H.264 encoding with libx264 at CRF 18 in Main profile for maximum compatibility; encapsulation in the Matroska container with libavformat's mkv muxer. The resulting MKV includes the total video duration in the container metadata, required for Plex and Kodi to correctly display the progress bar. The video track contains no audio (GIFs have no audio), which is perfectly valid in MKV. After conversion, the user can use MKVToolNix to add an audio or subtitle track to the file without re-encoding the video.