Who has the highest presidential IQ on Simonton 2C?
John Quincy Adams is 175 on Table 1 II-C. That is the top of a historiometric ranking, not a test leaderboard.
QuestionWhich US president has the highest IQ?
Adams is 175
John Quincy Adams’s II-C value is 175.0—the maximum in Table 1. The other three variants still sit between 165 and 170.
The next rung is 160
Thomas Jefferson and James Madison are 160.0 on II-C. John F. Kennedy is 159.8, displayed as 160. Bill Clinton is 159.
The low end is still an estimate
Ulysses S. Grant is 130 on II-C, the lowest of the 42. George W. Bush is 138.5, displayed as 139. None of these is a classroom IQ.
What the evidence supports