WCM (.wcm)

.wcm file signature | application/vnd.ms-works

WCM is a legacy file format associated with Microsoft Works, originally created by Microsoft for its Works suite. It was used to store document-related data and macros within Works, supporting personal and small-office word processing tasks. The format is obsolete and may not open in modern software, but it is generally safe to inspect; as with other legacy Microsoft files, users should treat unfamiliar files cautiously.

Safe

Magic Bytes

Offset 0


              D0 CF 11 E0 A1 B1 1A E1

Sources: Apache Tika

Extension

.wcm

MIME Type

application/vnd.ms-works

Byte Offset

Risk Level

Safe

Validation Code

How to validate .wcm files in Python

Python

def is_wcm(file_path: str) -> bool:
    """Check if file is a valid WCM by magic bytes."""
    signature = bytes([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1])
    with open(file_path, "rb") as f:
        return f.read(8) == signature

How to validate .wcm files in Node.js

Node.js

function isWCM(buffer: Buffer): boolean {
  const signature = Buffer.from([0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1]);
  return buffer.subarray(0, 8).equals(signature);
}

How to validate .wcm files in Go

func IsWCM(data []byte) bool {
    signature := []byte{0xD0, 0xCF, 0x11, 0xE0, 0xA1, 0xB1, 0x1A, 0xE1}
    if len(data) < 8 {
        return false
    }
    return bytes.Equal(data[:8], signature)
}

API Endpoint

GET /api/v1/wcm


              curl https://filesignature.org/api/v1/wcm

See the full API documentation for all endpoints and parameters.

Related Formats

.wdb .wps .wks

Frequently Asked Questions

What is a .wcm file?

A .wcm file is identified by the magic bytes D0 CF 11 E0 A1 B1 1A E1 at byte offset 0. WCM is a legacy file format associated with Microsoft Works, originally created by Microsoft for its Works suite. It was used to store document-related data and macros within Works, supporting personal and small-office word processing tasks. The format is obsolete and may not open in modern software, but it is generally safe to inspect; as with other legacy Microsoft files, users should treat unfamiliar files cautiously.

What are the magic bytes for .wcm files?

The magic bytes for WCM files are D0 CF 11 E0 A1 B1 1A E1 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .wcm file?

To validate a .wcm file, read the first bytes of the file and compare them against the known magic bytes (D0 CF 11 E0 A1 B1 1A E1) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .wcm files?

The primary MIME type for .wcm files is application/vnd.ms-works.

Is it safe to open .wcm files?

WCM (.wcm) 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.