Average IQ by State: All 50 States Ranked (2026 Data)

"Which states are the smartest?" is a question that generates passionate debate — and more than a little controversy. While no single number can capture the intelligence of millions of diverse people, researchers have used standardized test data, educational attainment statistics, and cognitive assessment surveys to estimate average cognitive ability by state.

The estimates below are synthesized from multiple data sources: NAEP (National Assessment of Educational Progress) scores, SAT/ACT performance data adjusted for participation rates, educational attainment data from the U.S. Census Bureau, and research by Richard Lynn and others who have published state-level IQ estimates. These are estimates, not definitive measurements — no study has administered clinical IQ tests to representative samples in every state.

Methodology and Data Sources

Estimating average IQ by state is inherently imperfect. Here is how researchers typically approach it:

• NAEP scores: The National Assessment of Educational Progress (often called "The Nation's Report Card") tests representative samples of 4th and 8th graders in every state on math and reading. These scores correlate strongly with IQ at the group level (r ~ 0.75-0.85).
• SAT/ACT adjustments: Raw SAT and ACT averages by state are misleading because participation rates vary wildly (in states where the SAT is mandatory, averages are lower due to the full range of test-takers). Researchers use statistical adjustments to account for this selection bias.
• Educational attainment: The percentage of adults with bachelor's degrees and advanced degrees correlates with state-level cognitive ability estimates.
• Direct estimation studies: Researchers like McDaniel (2006) published state IQ estimates derived from combining NAEP data with demographic adjustments. These remain the most widely cited state-level IQ figures.

The national average is approximately 98 (slightly below 100 because most norming samples overrepresent certain demographic groups). State estimates range from approximately 94 to 104 — a span of about 10 points, which is meaningful at the population level but modest compared to within-state variation.

All 50 States Ranked by Estimated Average IQ

The following table draws primarily from McDaniel (2006) estimates, cross-referenced with NAEP performance data and updated educational attainment figures. States are ranked from highest to lowest estimated average IQ.

Rank	State	Est. Avg IQ	Notes
1	Massachusetts	104.3	Highest NAEP scores, top education spending
2	New Hampshire	104.2	Consistently high NAEP performance
3	North Dakota	103.8	Strong rural education system
4	Vermont	103.8	Small class sizes, high per-pupil spending
5	Minnesota	103.7	Top-tier public education system
6	Montana	103.4	High NAEP scores relative to spending
7	Maine	103.4	Strong K-12 outcomes
8	Iowa	103.2	Above-average educational outcomes
9	Connecticut	103.1	High income, well-funded schools
10	Wisconsin	102.9	Strong Midwestern education tradition
11	South Dakota	102.8
12	New Jersey	102.8	High education spending, strong suburbs
13	Wyoming	102.4
14	Nebraska	102.3
15	Oregon	101.9
16	Kansas	101.7
17	Virginia	101.9	Strong NoVA education corridor
18	Washington	101.8	Tech industry concentration
19	Colorado	101.6	Highly educated transplant population
20	Idaho	101.4
21	Pennsylvania	101.4
22	Ohio	101.1
23	Indiana	100.7
24	Maryland	100.5	High income but wide disparities
25	Michigan	100.5
26	Missouri	100.2
—	National Average	~98	Baseline reference point
27	Utah	100.1
28	Alaska	99.7
29	Illinois	99.4	Wide Chicago vs. rural gap
30	New York	99.4	Massive within-state variation
31	Rhode Island	99.0
32	Delaware	98.7
33	North Carolina	98.4	Research Triangle lifts average
34	Oklahoma	97.8
35	Texas	97.4	Vast population diversity
36	Kentucky	97.4
37	Florida	97.3	Large retiree population skews data
38	Georgia	97.0	Atlanta metro vs. rural divide
39	Tennessee	96.8
40	South Carolina	96.4
41	Arizona	96.4
42	Arkansas	96.0
43	Nevada	95.8	Rapid population growth, transient workforce
44	West Virginia	95.7	Low education spending, brain drain
45	Hawaii	95.6	Unique demographic and testing context
46	Alabama	95.7	Below-average education funding
47	Louisiana	95.3	Persistent educational challenges
48	California	95.5	Extremely diverse, wide internal range
49	New Mexico	95.0	High poverty rate, rural access issues
50	Mississippi	94.2	Lowest NAEP scores, highest poverty

Important note: These estimates have margins of error of approximately 1-3 points. States ranked close together — for instance, the cluster between ranks 20 and 30 — are essentially indistinguishable given measurement uncertainty. Do not treat these rankings as precise orderings.

Top 10 States: What They Have in Common

The ten highest-ranked states — Massachusetts, New Hampshire, North Dakota, Vermont, Minnesota, Montana, Maine, Iowa, Connecticut, and Wisconsin — share several characteristics:

• Above-average education spending per pupil. Massachusetts spends over $18,000 per student annually, nearly double the lowest-spending states. Research consistently shows that education spending, when directed effectively, correlates with student achievement (Jackson, Johnson, and Persico, 2016).
• Lower poverty rates. Childhood poverty is one of the strongest negative predictors of cognitive test performance. The top 10 states all have below-average child poverty rates.
• Strong teacher quality. States like Massachusetts and Connecticut have relatively high teacher certification standards and compensation, attracting stronger candidates into the profession.
• Cultural emphasis on education. Several top-ranked states (Minnesota, Wisconsin, Iowa) have deep Scandinavian and German-American cultural roots that historically emphasized literacy and formal education.
• Lower population density (for some). Several top states are rural, with small class sizes and tight-knit school communities. However, this pattern is not universal — Massachusetts and Connecticut are among the most densely populated states.

Bottom 10 States: Common Challenges

The ten lowest-ranked states — Mississippi, New Mexico, California, Louisiana, Alabama, Hawaii, West Virginia, Nevada, Arkansas, and Arizona — face overlapping challenges:

• Higher poverty rates. Mississippi has the highest child poverty rate in the nation at approximately 28%. Poverty affects nutrition, home stability, access to books and technology, and parental availability — all of which impact cognitive development.
• Lower education spending. Many bottom-ranked states spend significantly less per pupil. Mississippi spends approximately $9,800 per student compared to Massachusetts's $18,000+.
• Teacher shortages. States with lower teacher pay — particularly in the rural South — struggle to attract and retain qualified educators, leading to higher reliance on emergency-certified teachers.
• Historical underinvestment. Decades of segregation, underfunding, and structural inequality have created educational deficits that persist across generations.

The California Paradox

California's low ranking surprises many people, given its status as a tech and innovation hub. The explanation lies in its extraordinary demographic diversity and within-state inequality. Silicon Valley and the Bay Area have some of the highest concentrations of STEM talent in the world, while the state also has large populations with limited educational access, high poverty rates in the Central Valley, and one of the most diverse immigrant populations in the country. State averages mask enormous variation — the "average" for California is almost meaningless given the internal spread.

Factors That Drive State-Level IQ Differences

1. Education Quality and Funding

Per-pupil spending correlates with state IQ estimates at approximately r = 0.40-0.50. This relationship is not merely about throwing money at schools — it reflects investments in teacher quality, smaller class sizes, early childhood education programs, and educational infrastructure. The Chetty, Friedman, and Rockoff (2014) research on teacher effectiveness showed that high-quality instruction has measurable, lasting effects on students' cognitive outcomes and lifetime earnings.

2. Poverty and Socioeconomic Status

Childhood poverty is the single strongest negative predictor of state-level cognitive scores. The mechanisms are well-documented: chronic stress (elevated cortisol impairs hippocampal development), nutritional deficiencies, reduced access to enriching experiences (books, museums, travel), less parental time available for reading and educational engagement, and lower-quality schools in low-income areas. Studies by Noble et al. (2015) found that family income was associated with brain surface area, particularly in regions associated with language, reading, and executive function.

3. Urbanization and Brain Drain

Some states experience "brain drain" — the migration of higher-IQ individuals to states with better economic opportunities. Young adults who score highest on cognitive tests are the most likely to leave states with limited job markets (West Virginia, Mississippi) for states with knowledge-economy hubs (Massachusetts, Virginia, Colorado). This migration pattern concentrates cognitive ability in destination states and depletes it in origin states, creating a self-reinforcing cycle.

4. Demographics and Immigration Patterns

States with large recent immigrant populations may show lower average IQ estimates partly because standardized tests are normed for native English speakers and may not accurately capture the cognitive abilities of people tested in a second language. As immigrant populations assimilate and second-generation children are educated in American schools, this gap narrows substantially — a pattern well-documented in the literature on immigrant cognitive adaptation (Hernandez, Denton, and Macartney, 2008).

5. Health and Environmental Factors

Lead exposure, prenatal healthcare access, childhood nutrition, and environmental toxins all affect cognitive development. States with older housing stock (higher lead paint risk), less access to prenatal care, and higher rates of childhood malnutrition tend to show lower average cognitive scores. The lead-IQ connection is one of the most robust findings in environmental health research — Lanphear et al. (2005) found that even low-level lead exposure was associated with IQ deficits of 2-5 points.

Why State IQ Rankings Should Be Interpreted Carefully

Before using this data to draw conclusions about any state or its residents, consider these critical caveats:

• Within-state variation dwarfs between-state variation. The difference between the highest and lowest state average is about 10 IQ points. The standard deviation within any given state is 15 points. This means the smartest 16% of Mississippi residents have higher IQs than the average Massachusetts resident.
• State averages are not destiny. Individuals in every state span the full IQ spectrum. A child born in Mississippi with access to good schools, nutrition, and stimulation can develop cognitive abilities equal to or exceeding anyone in Massachusetts.
• These estimates reflect systemic conditions, not inherent ability. The differences are driven by education policy, economic conditions, and health infrastructure — all of which are changeable through policy and investment.
• Measurement limitations are real. No study has administered gold-standard IQ tests to representative samples in every state. These are estimates derived from proxy measures (NAEP, SAT/ACT, educational attainment), each of which has its own biases and limitations.
• Correlation is not causation. States that score high on IQ estimates also tend to be wealthier, healthier, and more educated. Disentangling cause and effect is extremely difficult.

Can States Improve Their Average IQ?

Yes — and the evidence for this is strong. The Flynn Effect demonstrates that population-level IQ scores have risen dramatically worldwide over the past century, primarily through improvements in nutrition, education, and health care. At the state level, targeted interventions have produced measurable gains:

• Early childhood education: The Perry Preschool Project and Abecedarian Project showed IQ gains of 5-15 points for disadvantaged children who received quality early education, with effects persisting into adulthood.
• Lead abatement: The removal of lead from gasoline and paint was associated with population-level IQ increases of 2-5 points over the following decades (Reyes, 2015).
• Nutrition programs: School breakfast and lunch programs, WIC (Women, Infants, and Children), and iodine fortification have all been linked to improved cognitive outcomes at the population level.
• Education reform: Massachusetts's 1993 Education Reform Act invested heavily in teacher quality, standards, and funding — and the state went from middle-of-the-pack to the top of national rankings within a decade.

These findings suggest that state IQ differences are not fixed. They are the product of policies and conditions that can be changed. For individuals seeking to understand their own cognitive profile regardless of state averages, a proper assessment provides the most accurate picture.

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