What is the average IQ in Sierra Leone?

The average IQ in Sierra Leone is approximately 71, based on Becker (2019) (2019). This ranks Sierra Leone #185 out of 195 countries in our dataset. This score is considered below the global average on the global scale.

How does Sierra Leone's IQ compare to other Africa countries?

Sierra Leone ranks among the lower-scoring countries in Africa. Other Africa countries with similar scores include Liberia (71), Benin (70), Equatorial Guinea (72).

What factors influence IQ scores in Sierra Leone?

Key factors include: education quality and access (3.6 average years of schooling), literacy rate (43%), economic development (GDP per capita of $1,850), healthcare access (HDI: 0.477), nutrition, and urbanization levels. These environmental factors significantly affect measured cognitive test performance.

Is the IQ score for Sierra Leone reliable?

The score of 71 is an estimate based on Becker (2019) (2019). Like all national IQ estimates, it has limitations including varying sample sizes, potential cultural test bias, and the fact that within-country variation is always much larger than between-country differences. It should be interpreted as a rough approximation, not a precise measurement.

Average IQ in Sierra Leone

Sierra Leone has an average IQ of 71, ranking #185 out of 195 countries globally. This is considered below the global average on the worldwide scale.

Average IQ Score

Below 80 (Below 80) · Rank #185 of 195

Source: Becker (2019) (2019)

Key Statistics

Population

8,600,000

GDP per Capita (PPP)

$1,850

World Bank, 2023

Literacy Rate

43%

UNESCO, 2023

Human Development Index

0.477

UNDP, 2023

Mean Years of Schooling

3.6

Adults 25+

Education Expenditure

2.6%

% of GDP

Education System in Sierra Leone

Sierra Leone launched a free quality school education program in 2018. Instruction is in English, with ongoing recovery from civil war impacts on education infrastructure.

IQ and Economic Development

Sierra Leone's GDP per capita of $1,850 reflects a lower-income economy. Research shows a moderate correlation (r ≈ 0.7) between national GDP and measured IQ, though this relationship is complex and bidirectional.

With 3.6 average years of schooling and a 2.6% GDP investment in education, Sierra Leone has room to increase education investment relative to GDP.

Countries with Similar IQ Scores

Liberia

Africa

Saint Vincent and the Grenadines

São Tomé and Príncipe

Africa

Africa Rankings

#	Country	Avg IQ
1	Mauritius	92
2	Morocco	87
3	Tunisia	87
4	Egypt	86
5	Algeria	86
6	Seychelles	86
7	Libya	85
8	South Africa	84
9	Nigeria	84
10	Madagascar	84

Data Sources for Sierra Leone

IQ Score:Becker (2019) (2019) (from the NIQ Dataset v1.3.3, the most comprehensive meta-analysis of national cognitive testing studies).

GDP & Education Spending:World Bank (2023)

HDI & Schooling:UNDP Human Development Report (2023–2024)

Literacy Rate:UNESCO Institute for Statistics (2023)

Population:UN World Population Prospects (2024)

National IQ estimates are approximate and based on meta-analyses of available cognitive testing data (Becker, 2019; Lynn & Vanhanen, 2012; World Population Review, 2025). These scores reflect measured test performance and are influenced by education, nutrition, healthcare, and socioeconomic factors — they do not measure innate intelligence. Within-country variation is much larger than between-country differences. IQ tests developed in Western contexts may not translate fairly across all cultures. Interpret with appropriate caution.

See the full methodology on our main IQ by Country page for complete source descriptions and data quality notes.