Every U.S. President Ranked by IQ

From genius-level thinkers who shaped nations with pen and paper to self-taught leaders who ruled by instinct, America’s presidents have spanned every shade of intelligence. Some were bookish philosophers, others quick-witted pragmatists, and a few learned more from experience than education. This ranking explores all 46 U.S. presidents—from the brilliant minds of Jefferson and Adams to the gut-driven instincts of Jackson and Trump—through one lens: pure, book-smart intelligence. Who were the true scholars of the Oval Office, and who simply thought on their feet?