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IQ Distribution by Gender Calculator

Visualize male and female IQ distributions and compute the ratio of men to women at, above, or below a chosen score using the WAIS-IV Normative Sample.

Gender Distribution Calculator

Calculate the ratio between men and women at, above, or below a given IQ score.

Index Guide
VCIVerbal Comprehension
PRIPerceptual Reasoning
WMIWorking Memory
PSIProcessing Speed
GAIGeneral Ability Index (VCI + PRI)
FSIQFull Scale IQ (VCI + PRI + WMI + PSI)

Index Guide
VCIVerbal Comprehension
PRIPerceptual Reasoning
WMIWorking Memory
PSIProcessing Speed
GAIGeneral Ability Index (VCI + PRI)
FSIQFull Scale IQ (VCI + PRI + WMI + PSI)

About IQ Differences Between Men and Women

Research on IQ distributions by gender consistently finds that average general intelligence (g) scores are very similar for men and women. Most large, well-standardized test batteries show little to no reliable mean difference (around 2 points or less).

However, while the averages are similar, male IQ scores tend to show slightly larger standard deviations. Statistically, this produces greater male representation at both the lower and upper ends of the distribution.

The variance ratio (VR) is the ratio of male score variance to female score variance. A VR greater than one indicates the variance is greater for boys than for girls, while a VR less than one indicates greater variability in the scores for girls. When viewed as a descriptive statistic, Feingold (1992) suggested that a VR of 1.10 is probably the smallest meaningful effect.

Our calculator uses data from the nationally representative WAIS-IV norming sample (Wechsler, 2008) with a VR of 1.10 between males and females on FSIQ. This finding is also supported by larger nationally representative samples, like a UK study (Strand et al., 2006) of more than 320,000 eleven- to twelve-year-old children (VR = 1.13) and a study that tested almost every eleven-year-old in Scotland (Deary et al., 2003; VR = 1.12).

Differences are more noticeable in certain specific cognitive abilities. On average, females perform somewhat better on processing speed tasks (VR = 0.93, d = -0.30), while males show advantages in visuospatial tasks (VR = 1.21, d = 0.24).

For a detailed review of the evidence, including variability, spatial ability, biological and socio-cultural factors, see our full article on IQ differences between men and women.

Reference Studies

Deary, I. J., Thorpe, G., Wilson, V., Starr, J. M., & Whalley, L. J. (2003). Population sex differences in IQ at age 11: The Scottish mental survey 1932. Intelligence, 31(6), 533–542. https://doi.org/10.1016/S0160-2896(03)00053-9

Feingold, A. (1992). Sex differences in variability in intellectual abilities: A new look at an old controversy. Review of Educational Research, 62(1), 61–84.

Piffer, D. (2016). Sex differences in intelligence on the American WAIS-IV. Mankind Quarterly, 57(1), 25–33. https://doi.org/10.46469/mq.2016.57.1.3

Strand, S., Deary, I. J., & Smith, P. (2006). Sex differences in Cognitive Abilities Test scores: A UK national picture. British Journal of Educational Psychology, 76(3), 463–480. https://doi.org/10.1348/000709905x50906

Wechsler, D. (2008). Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) Manual. San Antonio, TX: Pearson.