IQ and income: what the research shows

IQ works mainly through schooling and job entry. A higher IQ makes it easier to stay in education and to qualify for demanding work, and so the link to education and occupation is strong. Income depends on much more: which industry you work in, hours, the labour market in your region, whether you run a business, inheritance, health and luck. Each adds variation that IQ does not touch.

A study in the United States by Jay Zagorsky (2007), using a national survey that followed a cohort of young adults, found that each extra IQ point was linked with higher annual income after other factors were held constant. It found no statistically distinguishable relationship between IQ and wealth, and no protection from financial difficulty at the top of the IQ range. Wealth has even more inputs than pay, including saving habits and inheritance.

Occupations differ in their typical scores, but the ranges overlap widely. Our IQ by job page shows published estimates, and they describe groups, not individuals.

Yes, and the income figure changes most. Strenze split his studies by the age at which income was measured. For people in their early twenties the correlation with income was barely above zero. It rose to .20 at ages 25 to 29 and .27 at 30 to 34, and after 40 it appeared to decline again, though not back to the early levels. The link to education stayed roughly stable, and the link to occupation rose through the twenties and then levelled off.

The reason is plain. Young people with high scores are often still studying or at the start of careers, so their early pay says little. Studies that measure income too early understate the link, and the single headline figure of .20 averages across ages.

Parental background is the obvious competitor. In Strenze's review, intelligence was not far ahead of parental SES as a predictor of success. Children from better-off families have higher test scores on average, so some of the link between IQ and income is shared background. Strenze also tested that idea directly. If the link were only a by-product of family background or school performance, those two should have outperformed intelligence as predictors, and they did not. He concluded that intelligence is an independent influence on success, alongside parental SES and school performance, which also matter.

Ritchie and Bates followed a large British cohort. They found that maths and reading ability at age 7 predicted socioeconomic status at 42 beyond the effect of parental status and childhood intelligence. Knowledge and skill gained at school matter in their own right.

Non-cognitive traits count too. Heckman, Stixrud and Urzua (2006) found that both cognitive and non-cognitive abilities, such as persistence and self-control, affect wages and schooling decisions. The IQ test validity guide sets out the other predictors of job performance, including the 2022 revision that put the validity of general mental ability near .31.

Take the top quarter of people by IQ. If income were unrelated to IQ, 25% of them would also be in the top quarter by income. If the correlation is .20 and both are normally distributed, the figure is about 34%. At .43 it is about 44%, and at .56 about 51%. These are calculated from the normal curve, not taken from a survey.

So a high IQ does tilt the odds, and two in three people in the top quarter of IQ are still not in the top quarter for income. The pattern is a shift in averages inside a large overlap. A person's own IQ tells you little about what they will earn.

Not cleanly. Correlation does not show direction, and several causes are mixed together. A higher IQ can lead to more education. More education also raises IQ scores: Ritchie and Tucker-Drob's 2018 meta-analysis found about 1 to 5 IQ points for each extra year of school. Family background affects both IQ and income. And IQ is itself partly heritable, while its environment still matters.

These links make it hard to say how much a person's income would change if their IQ changed. The studies describe how people with different scores differ on average.

Three points hold up. IQ has a real but modest link to income, and a stronger one to education and job level. Most variation in earnings is unrelated to IQ. And an average across thousands of people says little about any one of them: many people with high scores earn modestly, and many with average scores earn well.

The figures also depend on the sample, the test and the age when income was measured. Early-career pay is a poor guide to lifetime earnings. If you want to know where your own score sits, see what a good IQ is, and for the factor these studies measure, see the g factor.