Matroska stream file (.mkv)
.mkv file signature | video/x-matroska
Matroska is an open multimedia container format developed and maintained by the Matroska development team. It is used to store video, audio, subtitles, and chapter data in movies, television recordings, and online video distributions, including WebM-based content. The format is generally safe to open, though large files and embedded tracks can affect performance; it is not a legacy format.
Magic Bytes
Offset 0
1A 45 DF A3
Sources: Wikipedia, Gary Kessler, Neil Harvey FileSignatures
All Known Signatures
2 signature variants are documented for .mkv files across multiple sources.
| Hex Signature | Offset | Sources |
|---|---|---|
| 1A 45 DF A3 | 0 | Wikipedia, Gary Kessler, Neil Harvey FileSignatures |
| 1A 45 DF A3 93 42 82 88 6D 61 74 72 6F 73 6B 61 | 0 | Apache Tika |
Extension
.mkv
MIME Type
video/x-matroska
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .mkv files in Python
def is_mkv(file_path: str) -> bool:
"""Check if file is a valid MKV by magic bytes."""
signature = bytes([0x1A, 0x45, 0xDF, 0xA3])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .mkv files in Node.js
function isMKV(buffer: Buffer): boolean {
const signature = Buffer.from([0x1A, 0x45, 0xDF, 0xA3]);
return buffer.subarray(0, 4).equals(signature);
}How to validate .mkv files in Go
func IsMKV(data []byte) bool {
signature := []byte{0x1A, 0x45, 0xDF, 0xA3}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
/api/v1/mkv
curl https://filesignature.org/api/v1/mkv
See the full API documentation for all endpoints and parameters.
Related Formats
Frequently Asked Questions
What is a .mkv file?
A .mkv file is a Matroska stream file file. Matroska is an open multimedia container format developed and maintained by the Matroska development team. It is used to store video, audio, subtitles, and chapter data in movies, television recordings, and online video distributions, including WebM-based content. The format is generally safe to open, though large files and embedded tracks can affect performance; it is not a legacy format.
What are the magic bytes for .mkv files?
The magic bytes for Matroska stream file files are 1A 45 DF A3 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .mkv file?
To validate a .mkv file, read the first bytes of the file and compare them against the known magic bytes (1A 45 DF A3) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .mkv files?
The primary MIME type for .mkv files is video/x-matroska.
Is it safe to open .mkv files?
Matroska stream file (.mkv) files are generally safe to open. They are classified as low risk because they primarily contain data rather than executable code. However, always ensure files come from a trusted source.