As of 2025, Sri Lanka records the highest average IQ in South Asia, with a score of 102, placing the country among the world’s top 12 nations for average IQ, according to data from the International IQ Test (IIT).
The findings are based on results from 1,352,763 participants worldwide who completed the same standardized IQ test online. The research also draws on extensive studies of national IQs conducted by psychologist Richard Lynn in collaboration with Tatu Vanhanen.
According to IIT, the global average IQ is 100, a benchmark surpassed by Sri Lanka’s national average. A total of 2,840 participants from Sri Lanka were assessed in the study. China ranked first globally with the highest average IQ of 107.
The study notes that IQ scores often reflect the quality of education systems, healthcare, and access to resources within a country. Several factors are identified as influencing national IQ levels, including health conditions, nutrition, intellectual engagement, and genetics.
Research cited by IIT indicates that good dietary habits are linked to higher IQ levels, with a 2024 study showing that children with balanced nutrition tend to score higher on intelligence tests. Intellectual activities also play a role; a 2022 study found that playing chess regularly can improve children’s IQ, while a 1962 study showed bilingual children outperform monolingual peers on intelligence tests.
Genetics is another significant factor, with a 2013 twin study suggesting that between 50% and 80% of IQ variation can be attributed to genetic influences.
“Countries with strong healthcare systems, healthy dietary practices, and cultures that encourage intellectual stimulation tend to have populations with higher average IQ levels,” the IIT report stated.
