— Education & cognition
High school graduates (no college) — average IQ
Published data on cognitive ability by educational attainment consistently places high school graduates (no college) at an average IQ around 97 — the 42th percentile of the general adult population.
High school graduates who don't continue to college average just below the population mean. Modern selection effects (more people going to college) push this group's average slightly down from earlier decades.
What this average really tells you
Education-by-IQ averages reflect selection effects, not causation. Higher-IQ people are more likely to be admitted to and complete higher levels of education, so the averages compound through filtering at each stage:
- Completing high school
- Being admitted to college
- Completing a bachelor's degree
- Being admitted to graduate school
- Completing a graduate degree
Each stage filters more strongly on cognitive ability, which is why average IQ rises monotonically with educational attainment.
What it does NOT tell you
An education-level average is not a cap or a requirement:
- There are many high school graduates (no college) scoring well above 112
- And many high school graduates (no college) scoring well below 82
- Lifetime achievement correlates with conscientiousness, motivation, opportunity, and circumstance — not just IQ
Compare with other education levels
- High school dropouts — average IQ 87
- Some college (no degree) — average IQ 104
- Bachelor's degree holders — average IQ 113
- Master's degree holders — average IQ 117
- PhD holders — average IQ 125