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ACFM (.acfm)

.acfm file signature | application/x-font-adobe-metric

Safe

Magic Bytes

Offset 0
53 74 61 72 74 46 6F 6E 74 4D 65 74 72 69 63 73

Sources: Apache Tika

Extension

.acfm

MIME Type

application/x-font-adobe-metric

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .acfm files in Python

Python
def is_acfm(file_path: str) -> bool:
    """Check if file is a valid ACFM by magic bytes."""
    signature = bytes([0x53, 0x74, 0x61, 0x72, 0x74, 0x46, 0x6F, 0x6E, 0x74, 0x4D, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73])
    with open(file_path, "rb") as f:
        return f.read(16) == signature

How to validate .acfm files in Node.js

Node.js
function isACFM(buffer: Buffer): boolean {
  const signature = Buffer.from([0x53, 0x74, 0x61, 0x72, 0x74, 0x46, 0x6F, 0x6E, 0x74, 0x4D, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73]);
  return buffer.subarray(0, 16).equals(signature);
}

How to validate .acfm files in Go

Go
func IsACFM(data []byte) bool {
    signature := []byte{0x53, 0x74, 0x61, 0x72, 0x74, 0x46, 0x6F, 0x6E, 0x74, 0x4D, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73}
    if len(data) < 16 {
        return false
    }
    return bytes.Equal(data[:16], signature)
}

API Endpoint

GET /api/v1/acfm
curl https://filesignature.org/api/v1/acfm

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .acfm file?

A .acfm file is a ACFM file.

What are the magic bytes for .acfm files?

The magic bytes for ACFM files are 53 74 61 72 74 46 6F 6E 74 4D 65 74 72 69 63 73 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .acfm file?

To validate a .acfm file, read the first bytes of the file and compare them against the known magic bytes (53 74 61 72 74 46 6F 6E 74 4D 65 74 72 69 63 73) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .acfm files?

The primary MIME type for .acfm files is application/x-font-adobe-metric.

Is it safe to open .acfm files?

ACFM (.acfm) 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.