UUencoded BASE64
application/octet-stream
Magic Bytes
Offset: 0
62 70 6C 69 73 74
The b64 file format is a binary-to-text encoding scheme standardized by the Internet Engineering Task Force to represent binary data in a portable ASCII string format. It is primarily used for transmitting binary attachments over text-based protocols like SMTP or embedding media assets directly into web documents. While this format ensures data integrity during transfer, it provides no native encryption or security and should not be used for protecting sensitive content.
Validation Code
How to validate .b64 files in Python
Python
def is_b64(file_path: str) -> bool:
"""Check if file is a valid B64 by magic bytes."""
signature = bytes([0x62, 0x70, 0x6C, 0x69, 0x73, 0x74])
with open(file_path, "rb") as f:
return f.read(6) == signatureHow to validate .b64 files in Node.js
Node.js
function isB64(buffer: Buffer): boolean {
const signature = Buffer.from([0x62, 0x70, 0x6C, 0x69, 0x73, 0x74]);
return buffer.subarray(0, 6).equals(signature);
}
Go
func IsB64(data []byte) bool {
signature := []byte{0x62, 0x70, 0x6C, 0x69, 0x73, 0x74}
if len(data) < 6 {
return false
}
return bytes.Equal(data[:6], signature)
}API Endpoint
GET
/api/v1/b64
curl https://filesignature.org/api/v1/b64