Skip to content

Extended (.emf)

.emf file signature | image/emf

Extended Metafile (EMF) is a Windows graphics file format developed and maintained by Microsoft for storing device-independent vector images and drawing commands. It is used for clip art, illustrations, printer output, and exchange between applications that support Windows metafiles. As a legacy format, EMF remains widely supported for compatibility, and it is generally safe to open, though any file from an untrusted source should still be handled cautiously.

Safe

Magic Bytes

Offset 0
01 00 00 00

Sources: Apache Tika, Gary Kessler

Extension

.emf

MIME Type

image/emf

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .emf files in Python

Python 
def is_emf(file_path: str) -> bool:
    """Check if file is a valid EMF by magic bytes."""
    signature = bytes([0x01, 0x00, 0x00, 0x00])
    with open(file_path, "rb") as f:
        return f.read(4) == signature

How to validate .emf files in Node.js

Node.js 
function isEMF(buffer: Buffer): boolean {
  const signature = Buffer.from([0x01, 0x00, 0x00, 0x00]);
  return buffer.subarray(0, 4).equals(signature);
}

How to validate .emf files in Go

Go 
func IsEMF(data []byte) bool {
    signature := []byte{0x01, 0x00, 0x00, 0x00}
    if len(data) < 4 {
        return false
    }
    return bytes.Equal(data[:4], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Related Formats

.cgm .dwg .svg .svgz .wmf .ai

Frequently Asked Questions

What is a .emf file?

A .emf file is a Extended file. Extended Metafile (EMF) is a Windows graphics file format developed and maintained by Microsoft for storing device-independent vector images and drawing commands. It is used for clip art, illustrations, printer output, and exchange between applications that support Windows metafiles. As a legacy format, EMF remains widely supported for compatibility, and it is generally safe to open, though any file from an untrusted source should still be handled cautiously.

What are the magic bytes for .emf files?

The magic bytes for Extended files are 01 00 00 00 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .emf file?

To validate a .emf file, read the first bytes of the file and compare them against the known magic bytes (01 00 00 00) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .emf files?

The primary MIME type for .emf files is image/emf.

Is it safe to open .emf files?

Extended (.emf) 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.