When people ask about the average IQ in the UK, they usually want one clear number. In practice, you only get that number after you decide how you will calculate it and which data you will trust.
In this article, we share our findings using a population-weighted approach across England, Scotland, Wales, and Northern Ireland, based on our own nation-level averages.
Then we compare our UK-wide estimate with other published UK averages from external sources. The goal is clarity, not labels. These are group-level averages, and they do not say anything about any individual person.
If you want context before the numbers, it helps to read what IQ is and then see how scores are grouped on the IQ test scale.
Our population-weighted UK average based on our four-nation results
We start with our nation-level averages, which are already final for each UK nation.
- England 99.7
- Scotland 100.5
- Wales 97.9
- Northern Ireland 98.3
To convert those four figures into a single average IQ in the UK, we use population weights.
That means England counts more than Northern Ireland in the final UK figure, because it has a much larger population.
For the weights, we use the latest mid-year population estimates published for the UK nations.
Using that population-weighted method, our estimated average IQ in the UK is 99.6.
This UK-wide average is close to 100, which is what most modern IQ scales use as the midpoint of the reference distribution.
Small differences of one or two points between nations can happen for many reasons, including sampling and test format, so it is best to treat this as an estimate rather than a fixed national trait.
How we calculated the average IQ in the UK (our findings)
To estimate the average IQ in the UK, we started with our final average scores for the four UK nations:
- England: 99.7
- Scotland: 100.5
- Wales: 97.9
- Northern Ireland: 98.3
Because the nations have different population sizes, we used a population-weighted method rather than a simple mean.
For the weights, we used the latest mid-year population estimates for England, Scotland, Wales, and Northern Ireland from the UK official statistics dataset.
Based on that weighting, our estimated average IQ in the UK is: 99.6
This is an estimate based on our dataset and a transparent weighting method. It should be read as a broad indicator, not a definitive national fact.
Average IQ by UK nation (our results)
Here is our nation-level breakdown in one place:
| UK nation | Our average IQ |
|---|---|
| England | 99.7 |
| Scotland | 100.5 |
| Wales | 97.9 |
| Northern Ireland | 98.3 |
In our dataset, Scotland comes out highest, England is close behind, and Wales comes out lowest, with Northern Ireland slightly above Wales.
How our UK average compares with other published estimates
Different websites and compilations report slightly different UK-wide averages. That is normal, because they often combine different studies, time periods, tests, and adjustment methods.
Here is how our population-weighted UK estimate compares with three sources we could verify directly:
| Source | Reported UK average IQ |
|---|---|
| FreeIQtest.uk | 99.6 |
| CourseGate | 99.12 |
| World Population Review | 99.68 |
| Brght | 100.88 |
You can see that the numbers cluster tightly around 99 to 100. That is a small spread, and it is one reason we keep the wording moderately cautious throughout this article.
Why the numbers differ across sources
Even when three sources aim to measure the same thing, their averages can disagree for practical reasons:
- Different test types and scoring methods: Some datasets are built from standard IQ tests, while others use proxies, composites, or adjusted scores.
- Sampling differences: Who was tested, how they were recruited, and whether the sample is representative can all shift the mean.
- Time period and normalization: Results can vary by cohort and by how scores are normalized to an IQ-style scale.
- UK-wide vs nation-level construction: Some sources publish one UK number directly. Others require aggregation from regions or nations, which introduces extra choices.
The key takeaway is simple: treat any single published number as an estimate, and focus more on the overall range and consistency across sources than on tiny point differences.
How the UK compares globally
There is no single perfect global IQ ranking, and cross-country comparisons are especially sensitive to methodology. Still, large compilations can be useful for a rough context.
On World Population Review, the UK is listed at 99.68, which places it in a broad group of countries clustered around the high-90s to about 101.
Examples close to the UK on that list include:
- United States: 99.74
- Netherlands: 99.72
- Germany: 99.64
- Austria: 99.65
And examples that appear notably higher on the same list include:
- Japan: 106.40
- Singapore: 105.14
A practical way to interpret this is that the UK often appears close to the global “developed-country middle” on these compilations, rather than at either extreme.
If your interest is more about headline-grabbing extremes than national averages, you may also like the highest IQ in the world, because it explains why big IQ claims often need extra context.
How to read “average IQ in the UK” responsibly
A UK average is one number describing a distribution, not a label for individuals.
It does not mean:
- People in the UK are “smarter” or “less smart” than people elsewhere.
- Any UK nation is defined by its average.
- Small gaps of 1 to 2 points reflect meaningful real-world differences in individuals.
In most IQ-style distributions, the majority of people cluster relatively close to the mean, and the spread within each nation is much larger than the gap between national averages. If you want a clear mental model for that, the IQ test scale is the best quick reference.
Summary
- Our population-weighted estimate of the average IQ in the UK, calculated from our four-nation averages, is 99.6.
- Other published UK-wide estimates we checked are very close, including 99.12 (CourseGate), 99.68 (World Population Review), and 100.88 (Brght).
- The UK typically appears in the same broad range as several other high-income countries on large compilations, rather than at the very top or bottom.