What is the strongest birth control pill?

Hard to say: If you mean - which is most effective at preventing pregnancy, they are mostly comparable, except that the pills with extended duration of active pills (the ones that only have 2 or 4 days of placebo at the end of the pack) are thought to be slightly more effective at preventing an egg from starting to form during the pill-free week. If you mean the highest dose of estrogen: usu. 35mcg is highest.