There is no universally accepted answer to which U.S. president had the “highest IQ,” because most presidents never took modern, standardized IQ tests and many of the numbers online are just retroactive estimates or guesses.

What most lists claim

Many popular rankings and videos that try to estimate “presidential IQs” tend to put John Quincy Adams at the top, often giving him a supposed IQ in the high 160s or even around 175.

Other names that frequently appear near the top in these estimates include:

  • Thomas Jefferson (often listed around 160)
  • John F. Kennedy (high 150s or around 160, depending on the source)
  • Bill Clinton (high 150s in several estimate-based lists)

These rankings usually mix a few documented test scores (for more modern presidents) with a lot of historical inference based on education, writings, and achievements.

Why these IQ rankings are unreliable

Experts and even many casual commentators point out that these presidential IQ charts are largely speculative.

Key problems:

  • Most early presidents lived long before IQ testing existed, so any number attached to them is an estimate, not a recorded score.
  • Different websites and videos use different methods and can disagree by more than 10 points for the same person.
  • Commenters on history and politics forums regularly note that these lists are “just opinions” and caution people not to treat them as hard facts.

Because of this, historians tend to talk about intellectual ability (education, writing, strategic thinking) rather than a specific IQ number.

Best honest answer

  • If someone insists on a name from popular internet lists: John Quincy Adams is most often claimed to have the highest IQ of any U.S. president.
  • If the goal is accuracy: there is no scientifically verified ranking of presidential IQs, and any exact number you see is an estimate, not a proven measurement.

Meta description: Curious which president had the highest IQ? Many modern lists name John Quincy Adams, but historians stress that nearly all presidential IQ numbers online are speculative estimates, not verified scores.

Information gathered from public forums or data available on the internet and portrayed here.