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External Websites
- National Center for Biotechnology Information - PubMed Central - IQ and Human Intelligence.
- MedicineNet - How Do I Know My IQ? IQ Ranges & Average Scores
- Verywell Mind - What's the Average IQ?
- Mensa International - What is IQ?
- Campus Manitoba PressbooksEDU Network - Standardization and the Intelligence Quotient
- Simply Psychology - IQ Vs EQ: Why Emotional Intelligence Matters More Than You Think
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies.Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Thank you for your feedback
Our editors will review what you’ve submitted and determine whether to revise the article.
External Websites
- National Center for Biotechnology Information - PubMed Central - IQ and Human Intelligence.
- MedicineNet - How Do I Know My IQ? IQ Ranges & Average Scores
- Verywell Mind - What's the Average IQ?
- Mensa International - What is IQ?
- Campus Manitoba PressbooksEDU Network - Standardization and the Intelligence Quotient
- Simply Psychology - IQ Vs EQ: Why Emotional Intelligence Matters More Than You Think
Also known as: intelligence quotient
Written and fact-checked by
The Editors of Encyclopaedia Britannica
Last Updated: •Article History
IQ
Category: Science & Tech
- Related Topics:
- human intelligence
- psychological testing
Recent News
Mar. 26, 2024, 4:04 AM ET (The Standard)
Study shows children who grow in children homes have low IQs and stunted growth
Mar. 6, 2024, 5:19 AM ET (The Guardian)
The state took these children away – then used their parents’ low IQ scores to keep them apart
IQ, (from “intelligence quotient”), a number used to express the relative intelligence of a person. It is one of many intelligence tests.
IQ was originally computed by taking the ratio of mental age to chronological (physical) age and multiplying by 100. Thus, if a 10-year-old child had a mental age of 12 (that is, performed on the test at the level of an average 12-year-old), the child was assigned an IQ of 12/10 × 100, or 120. If the 10-year-old had a mental age of 8, the child’s IQ would be 8/10 × 100, or 80. Based on this calculation, a score of 100—where the mental age equals the chronological age—would be average. Few tests continue to involve the computation of mental ages. See also Lewis Terman; Alfred Binet.
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This article was most recently revised and updated by Jeannette L. Nolen.
