trying to tell how far along I am

My last period was august 30, I've been trying to get an ultrasound I've taken about 10 pregnancy tests home and at the doctors and have yet to have an US all I wanna know is how far along I am does anyone know how to calculate to find out? HELP! I clearly don't need to take anymore tests or pee in anymore cups to find out because it's clear I have my second beautiful blessing growin inside of me lol I just wanna know how far I am