Average IQ
by Country.

1 Quick Answer

Updated September 19, 2026 by Structural. There is no single universally authoritative IQ number for every country. Different lists use different tests, years, sample frames, and adjustment methods. This page uses one recent primary dataset: the International IQ Test country ranking published on January 1, 2026, based on 1,212,714 people who took the same test in 2025.

The Australian review compares regional test norms, historical study rows and online participants without presenting them as one national measure.

The United States evidence review traces the US figures to their norm references, historical samples and online participants.

Cross-country comparison also collides with test content itself: vocabulary and general knowledge items travel poorly across languages. That is the problem a culture fair IQ test tries to reduce by leaning on figural and spatial material instead of culturally loaded content.

For a product focused audit of that provider rather than a country or education ranking, read our International IQ Test review.

In that dataset, South Korea ranks first among sovereign states at 106.97. The United States is listed at 101.04 from 22,605 participants. Territories with enough participants, such as Hong Kong and Taiwan, are shown separately in the source but rolled into their sovereign country in the main ranking.

2 Country Lookup Tool

Use this tool to search a country, compare its score with the dataset mean of 100, and inspect sample size before drawing conclusions. The default selection is the United States because it is one of the most common starting points for this topic.

3 Top 10 Countries in This 2026 Dataset

This top-10 table uses the same sovereign-state ranking throughout the page. Territories such as Hong Kong and Taiwan are shown separately later because the source lists them separately but rolls them into their sovereign country in the main ranking.

4 Full Searchable Country Table

The table below shows all 137 countries included in the main ranking, with the source's own two-decimal means and participant counts. The population behind every row is the same self-selected pool described above the lookup tool: people who took one online test in 2025, not a representative sample of any country. Click a row to load that country into the lookup panel above.

5 How to Read Average IQ by Country Carefully

Country-level IQ tables attract attention because they look simple. In reality, they compress many difficult issues into one number. If you want to read them seriously, keep these limits in view:

• Country averages are not individual destiny. A country mean does not tell you your own score, your own percentile, the shape of any one person's cognitive profile, or how occupational selection works inside a country. For the career-specific version, use Average IQ by Profession. For the shape of your own profile rather than a national mean, measure it across six cognitive domains.
• Sample frame matters. A self-selected online sample is not the same as a nationally representative norming study. It can overrepresent some groups and underrepresent others.
• Language and access matter. Internet availability, English ability, translation quality, and willingness to take online tests all shift who appears in the sample.
• Education and development matter. Country averages often track schooling, health, literacy, and general opportunity at least as much as anything people try to label as raw intelligence.
• Small differences are easy to overread. A gap of 0.5 to 1.5 points can disappear under a different sample year, a different instrument, or a different adjustment method.

This is why the best use of a page like this is comparison inside one known dataset, plus methodological caution. It is not to pretend a country's published mean is a final scientific verdict. Aggregate tables in unrelated subjects break the same way, and the best known chart of scores by music taste matched school level averages to school level popularity without testing a single listener.

6 Why Average IQ by Country Lists Disagree

If you search this topic, you will quickly notice that country IQ numbers often do not match from one site to another. That is not a bug. It is what happens when people combine very different methods. Cross national correlations are where misuse concentrates; the religiosity and IQ research shows how quickly an aggregate association gets misread as a statement about individuals. A personal score depends on method in the same way: the reliability, validity and norms behind an accurate score are properties of one instrument given one way, and a country mean assembled from mismatched tests shares none of them.

The Germany evidence review identifies the samples and transformations behind the German figures in historical and online tables.

The Canadian evidence review explains why local norms, US norms and an online participant table produce different Canadian figures.

• Some tables use one live test dataset. That is what this page does.
• Some tables use older national-IQ estimate books or adjusted compilations. Those often blend direct test results, educational proxies, and imputation from nearby countries.
• Some sites mix territories and sovereign states inconsistently. Hong Kong, Taiwan, Puerto Rico, and similar entries often move in or out depending on the publisher.
• Some lists are more controversial than others. Older cross-national estimate sets have drawn heavy criticism over methodology, objectivity, and the use of best-guess estimates for countries without direct data.

That is why this page does not pretend there is a perfect global number for every country. Instead, it shows one recent ranking, names the source clearly, shows sample sizes, and surfaces the limits up front. The mismatch becomes obvious once the instruments themselves are laid side by side, and an inventory of the major tests by publisher, edition, age range and administration mode shows that a full Wechsler battery and a short matrices screener are not the same measurement to average together.

Territories Listed Separately in the Primary Source

The source also reports several territories separately, while combining them into their sovereign country for the main ranking. They are shown here because users often search for them directly.

7 Frequently Asked Questions

8 Sources and Related Guides

If you want to interpret country averages more responsibly, pair this page with norming, score, and age-context resources instead of reading the country table in isolation.

After that, benchmark country averages against score-specific interpretation pages so the numbers stay tied to recognizable points on the IQ scale:

• International IQ Test: Average IQ by Country 2026 - primary ranking dataset used in this tool.
• World Population Review: Average IQ by Country 2026 - secondary summary that contextualizes alternative lists and methodological disputes.
• Nisbett, R.E. et al. (2012). Intelligence: new findings and theoretical developments. American Psychologist, 67(2). The broad APA review of what moves measured intelligence and what does not.
• Plomin, R. & Deary, I.J. (2015). Genetics and intelligence differences: five special findings. Molecular Psychiatry. Open access. The standard modern review of what twin and DNA evidence does and does not show.
• Trahan, L.H., Stuebing, K.K., Hiscock, M.K. & Fletcher, J.M. (2014). The Flynn effect: A meta-analysis. Psychological Bulletin. Open access. Scores rose about 2.31 points per decade across 285 studies, which is why norms age and older scores overstate standing.
• Voncken, L., Albers, C.J. & Timmerman, M.E. (2019). Improving confidence intervals for normed test scores. Behavior Research Methods. Open access. Documents the mean 100, SD 15 metric and the uncertainty that norming from samples adds to any score.
• Crawford, J.R., Garthwaite, P.H. & Slick, D.J. (2009). On percentile norms in neuropsychology. The Clinical Neuropsychologist, 23(7), 1173-1195. Three definitions of a percentile coexist in practice and can return different results for the same score.
• Pearson (2008). WAIS-IV Score Report sample. What a real report contains: every composite paired with a percentile rank, a 95% confidence interval and a qualitative description, never a bare number.
• Pearson Clinical Assessment Scientific Council (2023). Standardized Clinical Assessment for Practitioners: A Primer. How standard scores, percentile ranks and the standard error of measurement are meant to be read together.
• Pearson (2024). WAIS-5, Wechsler Adult Intelligence Scale, Fifth Edition. The current adult battery, covering ages 16:0 to 90:11 across five cognitive domains.