According to the book A Question of Intelligence by Daniel Seligman, the IQ’s of Richard Nixon and JFK were both tested in school at 143 and 119, respectively. The IQ of George W. Bush is not known, but he scored 1206 on his SAT back in the days when the test was much harder. Since the reading and math skills measured by the SAT relate closely to intelligence, psychologist Linda Gottfredson converted his SAT score into an IQ equivalent of 125. There’s some speculative information about Obama’s intelligence, but the IQ’s of Nixon, JFK, and GWB are the best established. Based on this very small sample, U.S. presidents have an average IQ of about 130 with a standard deviation of about 12, compared to the general U.S. population that has an average IQ of about 100 with a standard deviation of about 15. So although presidents tend to be much smarter than Americans as a whole, their IQ’s are less variable. In fact extrapolating from these statistics, one might expect that the smartest president in American history had an IQ of around 154 and the dullest had an IQ of around 106.
An average IQ of 130 is extremely high, putting one above nearly 98% of Americans. To put this number in perspective, Harvard, the most prestigious university in the entire world, also has an average IQ of 130. Even the dullest president in U.S. history was likely smarter than two thirds of Americans of his era. The high IQ’s of U.S. presidents demonstrates that America is meritocracy and that smart people get to the top.