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An Object Linking and Embedding (.dot)

.dot file signature | application/msword

An Object Linking and Embedding (OLE) Compound File is a structured storage format developed and maintained by Microsoft. It is used by Microsoft Office 97–2003 applications, including Word, Excel, PowerPoint, and related document templates. The format is legacy and largely superseded by newer Office file types; it has limited public documentation and, like other compound documents, should be handled cautiously when obtained from untrusted sources.

Safe

Magic Bytes

Offset 0
D0 CF 11 E0 A1 B1 1A E1

Sources: Apache Tika, Gary Kessler

All Known Signatures

9 signature variants are documented for .dot files across multiple sources.

Hex Signature Offset Sources
D0 CF 11 E0 A1 B1 1A E1 0 Apache Tika, Gary Kessler
4D 69 63 72 6F 73 6F 66 74 20 57 6F 72 64 20 36 2E 30 20 44 6F 63 75 6D 65 6E 74 2080 Apache Tika
44 6F 63 75 6D 65 6E 74 6F 20 4D 69 63 72 6F 73 6F 66 74 20 57 6F 72 64 20 36 2080 Apache Tika
4D 53 57 6F 72 64 44 6F 63 2112 Apache Tika
31 BE 00 00 0 Apache Tika
50 4F 5E 51 60 0 Apache Tika
FE 37 00 23 0 Apache Tika
DB A5 2D 00 00 00 0 Apache Tika
94 A6 2E 0 Apache Tika

Extension

.dot

MIME Type

application/msword

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .dot files in Python

Python
def is_dot(file_path: str) -> bool:
    """Check if file is a valid DOT 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 .dot files in Node.js

Node.js
function isDOT(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 .dot files in Go

Go
func IsDOT(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/dot
curl https://filesignature.org/api/v1/dot

See the full API documentation for all endpoints and parameters.

Related Formats

Frequently Asked Questions

What is a .dot file?

A .dot file is a An Object Linking and Embedding file. An Object Linking and Embedding (OLE) Compound File is a structured storage format developed and maintained by Microsoft. It is used by Microsoft Office 97–2003 applications, including Word, Excel, PowerPoint, and related document templates. The format is legacy and largely superseded by newer Office file types; it has limited public documentation and, like other compound documents, should be handled cautiously when obtained from untrusted sources.

What are the magic bytes for .dot files?

The magic bytes for An Object Linking and Embedding 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 .dot file?

To validate a .dot 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 .dot files?

The primary MIME type for .dot files is application/msword.

Is it safe to open .dot files?

An Object Linking and Embedding (.dot) 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.