another variant of "resetting administrator password"

A variant only partially answered by this codex link, which still says to use MD5 hashes.

The problem in short is: how to generate a valid hash? I tried this mainframe8 tool
but does not work. Valid hashes stored in my database are a few characters longer.

(I am still developing the webiste on my laptop, I could of course install a mailserver and ask for password recovery by email, but this is the last resort. It’s stupid, since I have full access to webserver and mysql server.)

Thanks a lot in advance.