Average IQ by country — how to read the data
Country-level average IQ figures are interesting, but they only make sense when you look at sample sizes, sampling methods, and the huge variation inside every country.
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What a country average actually is
A national average IQ is simply the mean score of the people from that country who took a particular test. It is not a fixed property of a nation. Different datasets — school samples, military conscripts, online volunteers — produce different numbers for the same country.
On this site, country pages are built from our own online dataset. A country appears only once at least 200 results from that country have been collected, so small samples with unstable averages are not shown.
Why sample size matters
An average built from 200 results is far more reliable than one built from 12. It also still carries a margin of error: with a few hundred submissions, the true long-run average can easily differ by a couple of points.
The country pages show the number of tests behind every figure so you can judge how much weight to give it.
- Larger samples → more stable averages
- Online samples → self-selected, not representative of the whole population
- Device and language access → can skew which groups participate
Correlation is not causation
Country averages correlate with education systems, income levels, nutrition, and test familiarity. None of those links proves that one factor causes the other, and none of them says anything about an individual person.
The range of scores within a single country is far larger than the gap between most national averages. Two randomly chosen people from the same country will usually differ by much more than the typical difference between country means.
How to use the country rankings
Treat the rankings as a snapshot of one dataset at one point in time — useful for curiosity, media references, and spotting long-term trends, not for judging individuals or making decisions about people, schools, or policies.
You can explore each country's breakdown by age, gender, education level, and study area, and compare it with the global dataset, from the country statistics page.
Frequently asked questions
It depends on the dataset. Rankings shift between studies and test formats, and small samples can produce misleading leaders — that is why we only publish countries with at least 200 results.
They are rough indicators, not precise measurements. Sampling method, test format, and language all affect national averages by several points.
We only create a country page after at least 200 results have been submitted from that country. Countries below the threshold appear once enough data accumulates.
No. A national average tells you nothing reliable about any individual — variation inside every country dwarfs the differences between averages.