Intelligence quotient (IQ) tests are a series of assessments used to determine the general intelligence of an individual in relation to other people the same age.

Many IQ tests are used today, and whether they measure actual intelligence or simply certain abilities continues to be controversial. IQ tests measure a specific functioning ability and may not accurately assess a person's talents or future potential. Results of any intelligence test may be culturally biased.

The Wechsler test and the Stanford-Binet Intelligence Scales (SC) are the most standardized and widely used exams. Average test results range from 90 - 110:

• A score below 70 indicates mental retardation.
• A person who scores 130 or higher is usually considered gifted, although different programs set different levels for this classification.
• A person with a score of 145-160 is usually classified as highly advanced or very gifted.
• A person with a score of 165 or higher is usually classified a genius.

Stebbins GT. Neuropsychological Testing. In: Goetz, CG. Textbook of Clinical Neurology. 3rd ed. St. Louis, Mo: WB Saunders; 2007: chap 27.