PRT
application/x-prt
Magic Bytes
Offset: 8
30 4D 33 43
PRT is a proprietary CAD file format developed by Kubotek, originally created for the CADKEY computer-aided design software ecosystem. It stores two-dimensional and three-dimensional geometric data, including wireframe models and solid geometry used extensively in mechanical engineering and manufacturing workflows. While now considered a legacy format largely superseded by newer versions, it remains safe for data exchange because it does not support executable scripts, macros, or embedded active content.
Validation Code
How to validate .prt files in Python
Python
def is_prt(file_path: str) -> bool:
"""
Check if file is a valid PRT by magic bytes.
Signature offset: 8 bytes
"""
signature = bytes([0x30, 0x4D, 0x33, 0x43])
with open(file_path, "rb") as f:
f.seek(8)
return f.read(4) == signatureHow to validate .prt files in Node.js
Node.js
function isPRT(buffer: Buffer): boolean {
// Signature offset: 8 bytes
const signature = Buffer.from([0x30, 0x4D, 0x33, 0x43]);
if (buffer.length < 12) return false;
return buffer.subarray(8, 12).equals(signature);
}
Go
func IsPRT(data []byte) bool {
// Signature offset: 8 bytes
signature := []byte{0x30, 0x4D, 0x33, 0x43}
if len(data) < 12 {
return false
}
return bytes.Equal(data[8:12], signature)
}API Endpoint
GET
/api/v1/prt
curl https://filesignature.org/api/v1/prt