M3U (.m3u)
.m3u file signature | audio/x-mpegurl
M3U is a plain-text playlist file format originally created for Winamp and now supported by many media players and streaming applications. It is used to list local media files or network streams, making it common for audio playlists, internet radio, and IPTV channel lists. The format is simple and generally safe, though playlists can reference remote resources or invalid paths, so files from untrusted sources should be reviewed carefully.
Magic Bytes
Offset 0
23 45 58 54 4D 33 55 0D 0A
Sources: Apache Tika
All Known Signatures
2 signature variants are documented for .m3u files across multiple sources.
| Hex Signature | Offset | Sources |
|---|---|---|
| 23 45 58 54 4D 33 55 0D 0A | 0 | Apache Tika |
| 23 45 58 54 4D 33 55 | 0 | Wikipedia |
Extension
.m3u
MIME Type
audio/x-mpegurl
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .m3u files in Python
def is_m3u(file_path: str) -> bool:
"""Check if file is a valid M3U by magic bytes."""
signature = bytes([0x23, 0x45, 0x58, 0x54, 0x4D, 0x33, 0x55, 0x0D, 0x0A])
with open(file_path, "rb") as f:
return f.read(9) == signatureHow to validate .m3u files in Node.js
function isM3U(buffer: Buffer): boolean {
const signature = Buffer.from([0x23, 0x45, 0x58, 0x54, 0x4D, 0x33, 0x55, 0x0D, 0x0A]);
return buffer.subarray(0, 9).equals(signature);
}How to validate .m3u files in Go
func IsM3U(data []byte) bool {
signature := []byte{0x23, 0x45, 0x58, 0x54, 0x4D, 0x33, 0x55, 0x0D, 0x0A}
if len(data) < 9 {
return false
}
return bytes.Equal(data[:9], signature)
}API Endpoint
/api/v1/m3u
curl https://filesignature.org/api/v1/m3u
See the full API documentation for all endpoints and parameters.
Related Formats
Frequently Asked Questions
What is a .m3u file?
A .m3u file is identified by the magic bytes 23 45 58 54 4D 33 55 0D 0A at byte offset 0. M3U is a plain-text playlist file format originally created for Winamp and now supported by many media players and streaming applications. It is used to list local media files or network streams, making it common for audio playlists, internet radio, and IPTV channel lists. The format is simple and generally safe, though playlists can reference remote resources or invalid paths, so files from untrusted sources should be reviewed carefully.
What are the magic bytes for .m3u files?
The magic bytes for M3U files are 23 45 58 54 4D 33 55 0D 0A at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .m3u file?
To validate a .m3u file, read the first bytes of the file and compare them against the known magic bytes (23 45 58 54 4D 33 55 0D 0A) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .m3u files?
The primary MIME type for .m3u files is audio/x-mpegurl.
Is it safe to open .m3u files?
M3U (.m3u) 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.