Average IQ: Male vs Female — Is There a Difference?

Where small differences do appear

The real story is in the specific abilities, not the overall score. Here the pattern is consistent across studies: a few tasks show men slightly ahead, a few show women slightly ahead, and the effect sizes are almost all small. The table below summarizes the best-established findings from meta-analyses. (Cohen's d is a standard measure of gap size: 0.2 is small, 0.5 medium, 0.8 large.)

Two things stand out. First, mental rotation — mentally turning a 3D object to see if it matches another — is the one place a genuinely moderate gap shows up favoring men; Voyer, Voyer, and Bryden's classic 1995 meta-analysis found men scoring close to a standard deviation above women on some versions, though modern estimates land lower and vary with task format. Second, the female advantages in verbal memory and processing speed are real but small, and they roughly offset the male spatial edge when you roll everything up into a full-scale IQ. That offsetting is exactly why the overall averages match.

The "greater male variability" hypothesis — what's actually claimed

Beyond averages, there is a separate and more contentious question: is one sex more spread out? The greater male variability hypothesis holds that men show a wider distribution of scores — more men at both the very top and the very bottom — even when the average is the same. If true, it would mean slightly more men than women at the extreme tails without either sex being "smarter" on average.

Here is the honest state of the debate as of 2026: the evidence is mixed and the interpretation is disputed. Some large datasets do report variance ratios slightly above 1.0 (for example, around 1.05–1.16 on some measures), which would mean modestly more male variability. But critics point out that these ratios are small, vary a lot between countries and cultures, can flip depending on which test and sample you use, and are sensitive to how you handle the data. A widely cited analysis of mathematics performance reported a variance ratio near 1.08 and argued that this effectively debunks a meaningful male-variability advantage — while other researchers counter that even that ratio is non-trivial at the extremes. The fair summary: there may be a small tendency toward greater male variability on some cognitive measures, but it is modest, inconsistent, and far from settled. It is not a basis for any claim that one sex is more intelligent.

Why "who's smarter" is the wrong question

Put the pieces together and the takeaway is clear. The averages are the same. The subtest differences are small and cut in both directions. The variability question is unresolved and, even at its largest, would only nudge the ratio at the extreme tails. In practical terms, the overlap between the male and female IQ distributions is enormous — far larger than the difference between them. This fits psychologist Janet Hyde's "gender similarities hypothesis," which reviewed decades of research and concluded that on most psychological measures, including cognitive ones, males and females are far more alike than different.

So if someone tells you their sex, you have learned essentially nothing about how they will score on an IQ test. Individual variation dwarfs group averages. The most useful number is your own — and the only way to get it is to actually take a properly scored test rather than reason from group statistics.

FAQ

Q: Do men have a higher IQ than women?

A: No. On overall general intelligence, the male and female averages are essentially the same — about 100 by design. A 2022 meta-analysis of modern Wechsler tests found a gap of roughly 0.81 IQ points, which is statistically non-significant. Neither sex has a meaningful IQ advantage.

Q: What is the average IQ for women?

A: About 100, the same as for men. IQ tests are standardized so the population average is 100 with a standard deviation of 15, and modern batteries are constructed to show no overall sex gap. Small differences appear only on specific subtests, not on full-scale IQ.

Q: Are there any real cognitive differences between the sexes?

A: Yes, but they are small and specific. Men tend to score slightly higher on mental rotation and some spatial tasks (Cohen's d around 0.5–0.7 for mental rotation), while women tend to score slightly higher on verbal-episodic memory (d ≈ 0.28) and processing speed. These roughly cancel out in the overall score.

Q: Is the "greater male variability" idea proven?

A: No — it is still debated. Some studies report modestly wider male score distributions (variance ratios slightly above 1.0), but the effect is small, varies across cultures and tests, and researchers disagree on how to interpret it. It does not support any claim that one sex is more intelligent.

References

• Hyde, J. S. (2005). The Gender Similarities Hypothesis. American Psychologist, 60(6), 581–592. American Psychological Association. apa.org
• Hirnstein, M., Stuebs, J., Moè, A., & Hausmann, M. (2023). Sex/Gender Differences in Verbal Fluency and Verbal-Episodic Memory: A Meta-Analysis. Perspectives on Psychological Science. PMC9896545
• The Impasse on Gender Differences in Intelligence: a Meta-Analysis on WISC Batteries (2022). Educational Psychology Review. Springer
• Sex differences in intelligence. Wikipedia (overview with primary-source citations, incl. Voyer et al. 1995 mental-rotation meta-analysis). Wikipedia

Last updated: July 13, 2026