What is the average IQ?
The average IQ is 100, by definition. IQ tests are scaled so that the typical person in the reference group scores exactly 100.
Why the average is always 100
An IQ score is not a count of correct answers. It compares your performance with a reference group and rescales the result so the average becomes 100 and the standard deviation 15. Whenever a test is re-normed, the average is reset to 100.
Average IQ by age
Because scores are compared within age groups, the average IQ is 100 at every age. Raw abilities do change: fluid reasoning and processing speed rise through the teens, peak in early adulthood and slowly decline, while knowledge-based abilities keep growing for decades. IQ Atlas adjusts for age so a 15-year-old and a 60-year-old are both compared fairly.
Average IQ by country
Published national averages are controversial: samples are often small or unrepresentative, tests aren't always comparable, and scores are strongly affected by education, health and nutrition. They say nothing about any individual.
The IQ Atlas world map shows something different and clearly labelled: the average score of people in each country who chose to take this test. It's a fun way to represent your country, not a measure of a population.
Has the average changed over time?
Yes. Raw test performance rose by about 3 IQ points per decade in many countries during the 20th century (the Flynn effect), mostly attributed to better education, nutrition and familiarity with abstract thinking. In some countries the rise has recently slowed or reversed.
Frequently asked questions
Is 110 a good IQ?
Yes. 110 is above average, higher than about 75% of people, in the “high average” range.
Is 90 a low IQ?
No. 90 is within the average range (90–109), where half of all people score.