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Chart-led pieces on how scores are distributed across countries, states, ages, jobs and education levels — always with the caveats attached.
Nearly every "IQ by profession" chart online traces to one 1945 study of wartime enlisted men, scored on a scale that is not even the one modern IQ tests use. Here is the real table — and what still holds up.
Identical twins raised in separate homes end up more alike on IQ than fraternal twins raised in the same one. That single, replicated pattern is the whole logic behind how heritability gets estimated — and behind why the number is so often misread.
OpenAI and Anthropic published figures for the same rival models within four days of each other. They do not match, and the reasons are the ones psychometrics named a century ago.
Two children born eleven months apart can land in the same school year, and the younger one reliably tests lower on cognitive and achievement measures for reasons that have nothing to do with ability and mostly fade by adulthood.
Tables ranking average IQ by degree level circulate constantly and are read as though schooling simply sorts people. Pooled longitudinal evidence puts the correlation at about 0.56, and a meta-analysis of more than 600,000 people found that education also raises scores.
The meta-analytic correlation between measured intelligence and earnings is around 0.23, which leaves roughly ninety-five per cent of the differences in pay to everything else. A 2026 analysis of two large US cohorts adds a second finding: your specific strengths carry a third to a half of the weight that general ability does.
On a mean-100, standard-deviation-15 scale, 130 sits at the 97.72nd percentile, which leaves about one person in 44 above it. Here is the rarity at every threshold — and why the figures stop describing real people long before they stop being calculable.
The tables that circulate as national IQ figures come from one compilation built out of whatever studies existed, in whatever years, on whatever samples. Several of the numbers were estimated rather than measured.
An IQ figure is meaningless without the scale it was measured on and the range around it. Every story here reports all three, or says plainly that the source did not.
Each story ends with the studies, datasets and documents it draws on, named and attributed, so you can go and read them yourself.
Spotted an error? Write to corrections@iqmetrics.org. Corrections are made on the story and noted at the bottom of it — never quietly.
Our IIF-certified assessment reports your score with its scale, percentile and confidence range — and a breakdown of the cognitive domains behind it.
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