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JPX (.jpx)

.jpx file signature | application/octet-stream

JPEG 2000format[18]

Safe

Magic Bytes

Offset 0
00 00 00 0C 6A 50 20 20 0D 0A 87 0A

Sources: Wikipedia

Extension

.jpx

MIME Type

application/octet-stream

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .jpx files in Python

Python 
def is_jpx(file_path: str) -> bool:
    """Check if file is a valid JPX by magic bytes."""
    signature = bytes([0x00, 0x00, 0x00, 0x0C, 0x6A, 0x50, 0x20, 0x20, 0x0D, 0x0A, 0x87, 0x0A])
    with open(file_path, "rb") as f:
        return f.read(12) == signature

How to validate .jpx files in Node.js

Node.js 
function isJPX(buffer: Buffer): boolean {
  const signature = Buffer.from([0x00, 0x00, 0x00, 0x0C, 0x6A, 0x50, 0x20, 0x20, 0x0D, 0x0A, 0x87, 0x0A]);
  return buffer.subarray(0, 12).equals(signature);
}

How to validate .jpx files in Go

Go 
func IsJPX(data []byte) bool {
    signature := []byte{0x00, 0x00, 0x00, 0x0C, 0x6A, 0x50, 0x20, 0x20, 0x0D, 0x0A, 0x87, 0x0A}
    if len(data) < 12 {
        return false
    }
    return bytes.Equal(data[:12], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .jpx file?

A .jpx file is a JPX file. JPEG 2000format[18]

What are the magic bytes for .jpx files?

The magic bytes for JPX files are 00 00 00 0C 6A 50 20 20 0D 0A 87 0A at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .jpx file?

To validate a .jpx file, read the first bytes of the file and compare them against the known magic bytes (00 00 00 0C 6A 50 20 20 0D 0A 87 0A) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .jpx files?

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

Is it safe to open .jpx files?

JPX (.jpx) 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.