Password generator for .htpasswd for .htaccess file

I'm trying to password protect a directory on my web site. I'm using
the password encryption generator located at
http://resma.net/tutorials/htaccess.php#

I can't seem to get my login to work. I get a authentication prompt
screen when trying to access the directory, but it won't authenticate.

I've noticed that every time I enter the same password into the
encryption tool, it generates a different password. How can this be?