1A 45 DF A3

WebM video file / Matroska stream file

category: file-signature
normalized: 1a45dfa3
confirmed: 2026-03-15
lookups: 1
source: https://www.garykessler.net/

WebM video file; Matroska stream file. File extension(s): WEBM, MKV. Kessler type: Multimedia.

Similar magic numbers

value	name	category
1A 45 DF A3 93 42 82 88	Matroska stream file	file-signature
1A 03	LH archive (old vers.-type 2)	file-signature
1A 02	LH archive (old vers.-type 1)	file-signature
1A 09	LH archive (old vers.-type 5)	file-signature
1A 0B	Compressed archive file	file-signature