D81 (.d81)
.d81 file signature | application/octet-stream
Commodore 641581 disk image (D81 format)
Magic Bytes
Offset 0
A0 33 44 A0 A0
Sources: Wikipedia
Extension
.d81
MIME Type
application/octet-stream
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .d81 files in Python
def is_d81(file_path: str) -> bool:
"""Check if file is a valid D81 by magic bytes."""
signature = bytes([0xA0, 0x33, 0x44, 0xA0, 0xA0])
with open(file_path, "rb") as f:
return f.read(5) == signatureHow to validate .d81 files in Node.js
function isD81(buffer: Buffer): boolean {
const signature = Buffer.from([0xA0, 0x33, 0x44, 0xA0, 0xA0]);
return buffer.subarray(0, 5).equals(signature);
}How to validate .d81 files in Go
func IsD81(data []byte) bool {
signature := []byte{0xA0, 0x33, 0x44, 0xA0, 0xA0}
if len(data) < 5 {
return false
}
return bytes.Equal(data[:5], signature)
}API Endpoint
/api/v1/d81
curl https://filesignature.org/api/v1/d81
See the full API documentation for all endpoints and parameters.
Frequently Asked Questions
What is a .d81 file?
A .d81 file is a D81 file. Commodore 641581 disk image (D81 format)
What are the magic bytes for .d81 files?
The magic bytes for D81 files are A0 33 44 A0 A0 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .d81 file?
To validate a .d81 file, read the first bytes of the file and compare them against the known magic bytes (A0 33 44 A0 A0) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .d81 files?
There is no officially registered MIME type for .d81 files. Systems typically use application/octet-stream as a generic fallback when handling this format.
Is it safe to open .d81 files?
D81 (.d81) 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.