I've got this function for encrypting passwords in Java, but somehow when I call MessageDigest, it returns a different result every time even though I call it with the same password. I wonder if I am initializing it wrong somehow. public String encrypt (String password) { MessageDigest md = MessageDigest.getInstance("SHA-1"); md.reset(); md.update(password.getBytes(Charset.forName("utf-8")),0,password.length()); String res = md.digest().toString(); }