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Microsoft Windows Media Audio/Video File (.wma)

.wma file signature | application/octet-stream

Microsoft Windows Media Audio/Video File(Advanced Systems Format)

Safe

Magic Bytes

Offset 0
30 26 B2 75 8E 66 CF 11 A6 D9 00 AA 00 62 CE 6C

Sources: Wikipedia, Gary Kessler

Extension

.wma

MIME Type

application/octet-stream

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .wma files in Python

Python 
def is_wma(file_path: str) -> bool:
    """Check if file is a valid WMA by magic bytes."""
    signature = bytes([0x30, 0x26, 0xB2, 0x75, 0x8E, 0x66, 0xCF, 0x11, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C])
    with open(file_path, "rb") as f:
        return f.read(16) == signature

How to validate .wma files in Node.js

Node.js 
function isWMA(buffer: Buffer): boolean {
  const signature = Buffer.from([0x30, 0x26, 0xB2, 0x75, 0x8E, 0x66, 0xCF, 0x11, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C]);
  return buffer.subarray(0, 16).equals(signature);
}

How to validate .wma files in Go

Go 
func IsWMA(data []byte) bool {
    signature := []byte{0x30, 0x26, 0xB2, 0x75, 0x8E, 0x66, 0xCF, 0x11, 0xA6, 0xD9, 0x00, 0xAA, 0x00, 0x62, 0xCE, 0x6C}
    if len(data) < 16 {
        return false
    }
    return bytes.Equal(data[:16], signature)
}

API Endpoint

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

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .wma file?

A .wma file is a Microsoft Windows Media Audio/Video File file. Microsoft Windows Media Audio/Video File(Advanced Systems Format)

What are the magic bytes for .wma files?

The magic bytes for Microsoft Windows Media Audio/Video File files are 30 26 B2 75 8E 66 CF 11 A6 D9 00 AA 00 62 CE 6C at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .wma file?

To validate a .wma file, read the first bytes of the file and compare them against the known magic bytes (30 26 B2 75 8E 66 CF 11 A6 D9 00 AA 00 62 CE 6C) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .wma files?

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

Is it safe to open .wma files?

Microsoft Windows Media Audio/Video File (.wma) 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.