Popis: MD5 is an extremely popular hashing algorithm but now has very well known collision issues. If you select lowercase hex as the output format, this will produce results identical to most md5() functions provided by programming languages and md5sum. If you're looking for the md5 hashes that begin with "$1$" please see the crypt(3) MD5 function on this website which will produce MD5 hashes directly compatible with some /etc/passwd files and .htpasswd files.