Python: How to check if file is encoded as UTF16

To determine if a file is encoded as UTF-16, you can check for the presence of a Byte Order Mark (BOM) at the beginning of the file. UTF-16 encoded files usually start with a BOM, which is 0xFEFF for little-endian and 0xFFFE for big-endian.

def is_utf16(filename):
    with open(filename, 'rb') as file:
        start =
        return start in [b'\xff\xfe', b'\xfe\xff']

# Example usage
filename = 'test.txt'
if is_utf16(filename):
    print(f"The file '{filename}' is encoded as UTF-16.")
    print(f"The file '{filename}' is NOT encoded as UTF-16.")