If I were smarter I could likely answer this question. I never tested for it but for anyone younger out there since its a general test and it normalizes for age I think the younger you take it the better for a high result but its good to do it while your still studying general things. So like in the US like the summer after two years of college as your courses are going to get to specialized at that point. Maybe after the first year or if you don’t go to college just after high school.