Matroska media container — file signature 1A 45 DF A3 at offset 0

For Matroska media container, hex signature is 1A 45 DF A3; offset is 0; extension is mkv mka mks mk3d webm, verified against its source on 2026-08-03.

What the source says

ki/Free_Lossless_Image_Format> Free Lossless Image Format | 1A 45 DF A3 | ␚Eߣ | 0 | mkv mka mks mk3d webm | <https://en.wikipedia.org/wiki/Matroska> Matroska media container, including <https://en.wikipedia.org/wiki/WebM> WebM | 4D 49 4C 20 | MIL␠ | 0 | stg | "SEAN : Session Analysis" Training file. Also used in compatible software "Rpw : <https://en.wikipe

— en.wikipedia.org, retrieved 2026-08-03

Source

• en.wikipedia.orghttps://en.wikipedia.org/wiki/List_of_file_signatures

Last verified against source: 2026-08-03. Due for re-check by 2027-08-03. This page as Markdown · OKF bundle · full dataset as JSON.