StuffIt compressed archive
application/x-stuffit
Magic Bytes
Offset: 0
53 74 75 66 66 49 74
StuffIt is a proprietary compressed archive format originally developed by Raymond Lau and later maintained by Smith Micro Software. Historically, it served as the standard compression method for the classic Mac OS environment, enabling users to bundle multiple files and resource forks into a single portable container. While now largely considered a legacy format superseded by ZIP and DMG, SIT files remain relatively safe to handle, though extraction requires specialized software like StuffIt Expander or compatible third-party utilities.
Validation Code
How to validate .sit files in Python
Python
def is_sit(file_path: str) -> bool:
"""Check if file is a valid SIT by magic bytes."""
signature = bytes([0x53, 0x74, 0x75, 0x66, 0x66, 0x49, 0x74])
with open(file_path, "rb") as f:
return f.read(7) == signatureHow to validate .sit files in Node.js
Node.js
function isSIT(buffer: Buffer): boolean {
const signature = Buffer.from([0x53, 0x74, 0x75, 0x66, 0x66, 0x49, 0x74]);
return buffer.subarray(0, 7).equals(signature);
}
Go
func IsSIT(data []byte) bool {
signature := []byte{0x53, 0x74, 0x75, 0x66, 0x66, 0x49, 0x74}
if len(data) < 7 {
return false
}
return bytes.Equal(data[:7], signature)
}API Endpoint
GET
/api/v1/sit
curl https://filesignature.org/api/v1/sit