IQ by Country and Continent

Two ways to compare countries

Nobody has ever given the same IQ test to a representative sample of people in every country. Any table of IQ by country is pieced together from other data. This page shows two of them side by side:

Neither is a true national IQ. The first is closer to what people are searching for, and the second is better documented. Reading them together gives a more honest picture than either alone.

IQ by continent

The averages below are weighted by population, so large countries count for more. Countries whose national IQ value is only an estimate copied from neighbours are left out of that column.

The last column shows how many countries in each continent have a World Bank score and a measured national IQ value. Continents follow the UN's regional groupings, with the Americas split into North (including Central America and the Caribbean) and South America. Oceania's national IQ figure rests on only 3 countries and is dominated by Australia.

Two things stand out. The order of continents is the same on both measures, apart from Oceania, which tops the national IQ column on the strength of only three countries. And the gaps on the World Bank scale are large: the average student in Europe scores about 150 points higher than the average student in Africa, almost half the distance between the minimum and advanced benchmarks. The rest of this page explains why those gaps exist and why the national IQ column is less precise than its decimal places suggest.

IQ by country: all countries

All 207 countries and territories in either dataset. Click a column heading to sort, or filter by continent or name. The last column shows what each national IQ value is based on, so you can judge it for yourself.

National IQ: Becker (2023), NIQ dataset V1.3.5. Values in grey italics are estimated from neighbouring countries, not measured. Learning score: World Bank harmonised test scores, Human Capital Index 2020. A dash means no value. On a phone, swipe the table sideways to see what each value is based on.

Where the national IQ figures come from

The idea of ranking whole countries by IQ was popularised by the psychologist Richard Lynn and the political scientist Tatu Vanhanen in IQ and the Wealth of Nations (2002), followed by updated books in 2006 and 2012. Today the most up-to-date version is the open NIQ dataset maintained by David Becker, a German psychologist who worked with Lynn.

In version 1.3.5, released in October 2023, each country's headline value combines up to three ingredients:

• IQ test samples: published studies in which a group in that country took a recognised test, often Raven's Progressive Matrices, rescaled so that British norms equal 100.
• School assessments: results from international studies such as PISA, TIMSS and PIRLS, converted to the IQ scale.
• Neighbours: where there is no data at all, the average of nearby countries.

Out of 201 countries with a value in the dataset.

Why the national IQ figures are disputed

National IQ tables are among the most contested numbers in psychology. The main problems are about data quality, not about whether IQ tests work.

Many values are not measured at all

In the current dataset, 51 of 201 values, about a quarter, are copied from neighbouring countries. The earlier picture was worse: in the 2002 book, direct evidence existed for only 81 of 185 countries, and the rest were "simply estimated" from neighbours, as the psychologist Ken Richardson pointed out in Heredity.

Small and unusual samples

Of the 130 countries with IQ test data, 32 rest on a single study and 30 on fewer than 500 people in total. Some of the samples were never meant to represent a country:

Old data and selective choices

Samples run from the 1940s to the 2010s. Average scores rose by about 3 points per decade in many countries through the 20th century (Pietschnig and Voracek, 2015), so a decades-old sample understates a country today. Which studies get included matters too. When Jelte Wicherts and colleagues systematically reviewed IQ studies in sub-Saharan Africa, they put the average at about 82 against British norms, not below 70 as Lynn had concluded, and found that Lynn and Meisenberg's judgements about which samples were "representative" tracked the samples' scores rather than how they were collected (Wicherts and others, 2010; rejoinder).

The anthropologist Rebecca Sear's review, still a preprint, sums up the case against: most data "originates from samples which are wholly unrepresentative of their national populations", and she concludes the datasets "should not be used to draw inferences about global variation in intelligence" (Sear, 2022).

Do the two measures agree?

Broadly, yes, which is why the general pattern is taken seriously even by many critics. In a large comparison, the psychologist Heiner Rindermann found that countries' results on student assessments and on IQ tests correlated at about .85 (Rindermann, 2007).

Our own check on the data in this table gives a similar figure, with an important catch:

• Across the 133 countries with both a World Bank score and a measured national IQ, the correlation is 0.85. But for most of these countries the national IQ value already includes converted school test results, so the two numbers are partly the same data.
• For the 36 countries whose value rests on IQ tests alone, the correlation drops to 0.42. These are mostly lower-income countries, exactly where the IQ samples are thinnest.

In other words, the national IQ figures are most believable where they lean on school assessments, and least believable where they stand on their own.

What drives differences between countries?

The countries at the top of both tables have long, well-funded schooling, good health care and nutrition, and children who are used to sitting written tests. Those at the bottom are among the poorest in the world, where many children leave school early or never attend. All of these things affect test scores:

• Schooling. A review of natural experiments found that each extra year of education raises IQ by about 1 to 5 points (Ritchie and Tucker-Drob, 2018).
• Change over time. The rise of about 3 points per decade in the 20th century happened far too fast to be genetic, and has been linked to better nutrition, health and schooling.
• Missing children. School assessments only test children in school. The World Bank team calls its figures "a conservative upper bound" for countries where many children are out of school (Angrist and others, 2021).

National IQ tables have also been used to argue that some populations are innately less intelligent. The data can't support that. When a quarter of values are guesses, many rest on a few dozen people, and scores move with schooling and health, the tables can't separate inborn ability from circumstance. Differences between individuals within any country are also far larger than the differences between country averages.

For what the average means within a country, see our guide to average IQ. For how tests set 100 in the first place, see the IQ scale and what IQ is.

Frequently asked questions

Sources

• Becker, D. (2023). The NIQ-dataset (V1.3.5). Chemnitz, Germany: national IQ values, sample records and method.
• World Bank. Harmonized test scores (HD.HCI.HLOS), Human Capital Index 2020, and population (SP.POP.TOTL), licensed CC BY 4.0.
• Angrist, N., Djankov, S., Goldberg, P. K. and Patrinos, H. A. (2021). Measuring human capital using global learning data. Nature, 592, 403–408.
• Wicherts, J. M., Dolan, C. V. and van der Maas, H. L. J. (2010). A systematic literature review of the average IQ of sub-Saharan Africans. Intelligence, 38(1), 1–20; and the rejoinder, Intelligence, 38(1), 30–37.
• Richardson, K. (2004). Review of IQ and the Wealth of Nations. Heredity, 92, 359–360.
• Sear, R. (2022). 'National IQ' datasets do not provide accurate, unbiased or comparable measures of cognitive ability worldwide. PsyArXiv preprint.
• Rindermann, H. (2007). The g-factor of international cognitive ability comparisons. European Journal of Personality, 21(5), 667–706.
• Pietschnig, J. and Voracek, M. (2015). One century of global IQ gains: a formal meta-analysis of the Flynn effect (1909–2013). Perspectives on Psychological Science, 10(3), 282–306.
• Ritchie, S. J. and Tucker-Drob, E. M. (2018). How much does education improve intelligence? A meta-analysis. Psychological Science, 29(8), 1358–1369.
• Standard country or area codes for statistical use (M49), United Nations: continent groupings.