Skip to content

JDF magic bytes (.jdf)

.jdf file signature: 4A 45 4F 4C 2E 4E 4D 52 | application/x-jeol-jdf

JDF is a file format developed and maintained by JEOL Ltd. for use with its scientific instruments and analysis software. It is used to store and exchange data from laboratory systems, including spectroscopy, microscopy, and related scientific measurement workflows. The format is generally safe and is mainly encountered in JEOL environments, though older files may require legacy software or converters.

Safe

Magic Bytes

Offset 0
4A 45 4F 4C 2E 4E 4D 52

Sources: Apache Tika

Extension

.jdf

MIME Type

application/x-jeol-jdf

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .jdf files in Python

Python 
def is_jdf(file_path: str) -> bool:
    """Check if file is a valid JDF by magic bytes."""
    signature = bytes([0x4A, 0x45, 0x4F, 0x4C, 0x2E, 0x4E, 0x4D, 0x52])
    with open(file_path, "rb") as f:
        return f.read(8) == signature

How to validate .jdf files in Node.js

Node.js 
function isJDF(buffer: Buffer): boolean {
  const signature = Buffer.from([0x4A, 0x45, 0x4F, 0x4C, 0x2E, 0x4E, 0x4D, 0x52]);
  return buffer.subarray(0, 8).equals(signature);
}

How to validate .jdf files in Go

Go 
func IsJDF(data []byte) bool {
    signature := []byte{0x4A, 0x45, 0x4F, 0x4C, 0x2E, 0x4E, 0x4D, 0x52}
    if len(data) < 8 {
        return false
    }
    return bytes.Equal(data[:8], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .jdf file?

A .jdf file is identified by the magic bytes 4A 45 4F 4C 2E 4E 4D 52 at byte offset 0. JDF is a file format developed and maintained by JEOL Ltd. for use with its scientific instruments and analysis software. It is used to store and exchange data from laboratory systems, including spectroscopy, microscopy, and related scientific measurement workflows. The format is generally safe and is mainly encountered in JEOL environments, though older files may require legacy software or converters.

What are the magic bytes for .jdf files?

The magic bytes for JDF (.jdf) files are 4A 45 4F 4C 2E 4E 4D 52 at byte offset 0. These bytes identify the file format more reliably than the extension alone.

How do I validate a .jdf file?

To validate a .jdf file, read the first bytes of the file and compare them against the known magic bytes (4A 45 4F 4C 2E 4E 4D 52) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .jdf files?

The primary MIME type for .jdf files is application/x-jeol-jdf.

Is it safe to open .jdf files?

JDF (.jdf) 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.