EFI (.efi)
.efi file signature | application/octet-stream
DOS MZ executableand its descendants (includingNEandPE)
Magic Bytes
Offset 0
4D 5A
Sources: Wikipedia
Extension
.efi
MIME Type
application/octet-stream
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .efi files in Python
def is_efi(file_path: str) -> bool:
"""Check if file is a valid EFI by magic bytes."""
signature = bytes([0x4D, 0x5A])
with open(file_path, "rb") as f:
return f.read(2) == signatureHow to validate .efi files in Node.js
function isEFI(buffer: Buffer): boolean {
const signature = Buffer.from([0x4D, 0x5A]);
return buffer.subarray(0, 2).equals(signature);
}How to validate .efi files in Go
func IsEFI(data []byte) bool {
signature := []byte{0x4D, 0x5A}
if len(data) < 2 {
return false
}
return bytes.Equal(data[:2], signature)
}API Endpoint
/api/v1/efi
curl https://filesignature.org/api/v1/efi
See the full API documentation for all endpoints and parameters.
Frequently Asked Questions
What is a .efi file?
A .efi file is a EFI file. DOS MZ executableand its descendants (includingNEandPE)
What are the magic bytes for .efi files?
The magic bytes for EFI files are 4D 5A at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .efi file?
To validate a .efi file, read the first bytes of the file and compare them against the known magic bytes (4D 5A) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .efi files?
There is no officially registered MIME type for .efi files. Systems typically use application/octet-stream as a generic fallback when handling this format.
Is it safe to open .efi files?
EFI (.efi) 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.