RealMedia streaming media file magic bytes (.rm)
.rm file signature: 2E 52 4D 46 | application/vnd.rn-realmedia
Category: Video
RealMedia (RM) is a multimedia container format created and maintained by RealNetworks for streaming audio and video. It was used for internet media delivery, especially in older web players, broadcasting systems, and downloadable clips distributed through RealPlayer. The format is now largely legacy, and files from untrusted sources should still be handled with standard caution, although the format itself is not typically associated with high security risk.
Magic Bytes
Offset 0
2E 52 4D 46
Sources: Apache Tika, Gary Kessler
Validation Code
How to validate .rm files in Python
def is_rm(file_path: str) -> bool:
"""Check if file is a valid RM by magic bytes."""
signature = bytes([0x2E, 0x52, 0x4D, 0x46])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .rm files in Node.js
function isRM(buffer: Buffer): boolean {
const signature = Buffer.from([0x2E, 0x52, 0x4D, 0x46]);
return buffer.subarray(0, 4).equals(signature);
}How to validate .rm files in Go
func IsRM(data []byte) bool {
signature := []byte{0x2E, 0x52, 0x4D, 0x46}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
/api/v1/rm
curl https://filesignature.org/api/v1/rm
See the full API documentation for all endpoints and parameters.
Related Formats
Frequently Asked Questions
What is a .rm file?
A .rm file is a RealMedia streaming media file. RealMedia (RM) is a multimedia container format created and maintained by RealNetworks for streaming audio and video. It was used for internet media delivery, especially in older web players, broadcasting systems, and downloadable clips distributed through RealPlayer. The format is now largely legacy, and files from untrusted sources should still be handled with standard caution, although the format itself is not typically associated with high security risk.
What are the magic bytes for .rm files?
The magic bytes for RealMedia streaming media file (.rm) files are 2E 52 4D 46 at byte offset 0. These bytes identify the file format more reliably than the extension alone.
How do I validate a .rm file?
To validate a .rm file, read the first bytes of the file and compare them against the known magic bytes (2E 52 4D 46) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .rm files?
The primary MIME type for .rm files is application/vnd.rn-realmedia.
Is it safe to open .rm files?
RealMedia streaming media file (.rm) 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.