My IQ TestThe IQ Guide
Plain-English, source-backed explanations of how intelligence is measured, what scores mean and what really helps you think more clearly. Start anywhere — every article links to related reading.
Understanding IQ
What Is IQ? A Clear Guide to the Intelligence Quotient
What IQ actually measures, where the idea came from (Binet, Wechsler), and what an IQ score can and cannot tell you.
The IQ Scale Explained: What Every Score Range Means
A plain-English breakdown of IQ score ranges, percentiles and classifications, from below 70 to 145 and above.
Famous People and IQ: The Scores, the Myths and the Reality
The IQ scores often attributed to Einstein, Hawking, Marilyn vos Savant and others — and how many of them are really estimates or myths.
IQ vs EQ: How Reasoning and Emotional Intelligence Differ
How IQ and emotional intelligence differ, how each is measured, and what research says about their role in work and relationships.
Averages and comparisons
Average IQ by Country: What the Data Can and Can't Show
Estimated national IQ averages with the methods behind them, the major criticisms, and why the numbers should be read carefully.
Average IQ by Profession: What Research Suggests
Typical IQ ranges reported for different occupations, why the ranges overlap so much, and what really predicts career success.
Average IQ by Age: How Thinking Abilities Change Over Time
Why the average IQ is 100 at every age, and how fluid and crystallized abilities actually rise and fall across the lifespan.
Average IQ in the US: What the Numbers Really Mean
What the average IQ in the United States is, why US norms define 100 on most tests, and how scores vary by state, age and education.
Average IQ in the UK: Data, Trends and Context
The average IQ in the UK, why it anchors many international comparisons, and what British cohort studies reveal about intelligence.
Average IQ in Europe: Estimates by Country
Estimated average IQ for European countries, how the figures were compiled, and why most of Europe falls within a narrow band.
Improving your thinking
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