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Minitab data file magic bytes (.mtw)

.mtw file signature: D0 CF 11 E0 A1 B1 1A E1 | application/octet-stream

The Minitab data file format (MTW) is a proprietary file format associated with Minitab, LLC, used to store worksheet data for the Minitab statistical analysis application. It is used for importing, organizing, and analyzing datasets in quality control, process improvement, and academic research workflows. The format is generally considered safe; as a legacy Minitab worksheet format, it may require compatible software or conversion for use in newer versions.

Safe

Magic Bytes

Offset 0
D0 CF 11 E0 A1 B1 1A E1

Sources: Gary Kessler

Extension

.mtw

MIME Type

application/octet-stream

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .mtw files in Python

Python 
def is_mtw(file_path: str) -> bool:
    """Check if file is a valid MTW 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 .mtw files in Node.js

Node.js 
function isMTW(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 .mtw files in Go

Go 
func IsMTW(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/mtw
curl https://filesignature.org/api/v1/mtw

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .mtw file?

A .mtw file is a Minitab data file. The Minitab data file format (MTW) is a proprietary file format associated with Minitab, LLC, used to store worksheet data for the Minitab statistical analysis application. It is used for importing, organizing, and analyzing datasets in quality control, process improvement, and academic research workflows. The format is generally considered safe; as a legacy Minitab worksheet format, it may require compatible software or conversion for use in newer versions.

What are the magic bytes for .mtw files?

The magic bytes for Minitab data file (.mtw) files are D0 CF 11 E0 A1 B1 1A E1 at byte offset 0. These bytes identify the file format more reliably than the extension alone.

How do I validate a .mtw file?

To validate a .mtw 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 .mtw files?

There is no officially registered MIME type for .mtw files. Systems typically use application/octet-stream as a generic fallback when handling this format.

Is it safe to open .mtw files?

Minitab data file (.mtw) 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.