IQ (Intelligence Quotient) tests are standardized assessments of cognitive ability. Scores are calibrated so the average is 100, with a standard deviation of 15. This means approximately 68% of people score between 85 and 115, and only about 2% score above 130.
There is no single official definition of 'genius' IQ, but different organizations and researchers use different thresholds: Mensa accepts the top 2% (IQ 130+). Many psychologists use 140+ as their threshold for 'genius.' Some researchers, like Lewis Terman who launched the famous 'Genetic Studies of Genius,' used 140 as the cutoff for his gifted cohort.
IQ ranges and their typical labels (which vary by source): 130–144 is 'Gifted' or 'Highly Gifted'; 145–159 is 'Genius'; 160–179 is 'High Genius'; 180+ is 'Unmeasurable Genius' or 'Profoundly Gifted.' These labels are informal — there is no universally agreed taxonomy.
Most verified high-IQ claims in history are disputed or unverifiable. Marilyn vos Savant recorded a score of 228 in the Guinness Book of World Records in the 1980s (using an outdated childhood ratio IQ scale). William James Sidis is estimated at 250–300, again on outdated scales. These extreme figures are not comparable to modern IQ scores.
More important than any threshold: IQ score correlates moderately with academic achievement and job performance in cognitively demanding roles, but correlation is not destiny. Many people with very high IQs achieve little, and many transformative geniuses (particularly creative and entrepreneurial ones) score in the 'merely' gifted range.
Frequently Asked Questions
What IQ is considered a genius?
Most psychologists use 140+ as the threshold for 'genius,' though Mensa's top 2% cutoff (IQ 130) and other frameworks vary. There is no single universal definition.
What was Einstein's IQ?
Einstein never took a standardized IQ test. The commonly cited figure of 160 is a retrospective estimate with no documentary basis. His actual cognitive profile — exceptional visual-spatial reasoning and physical intuition — may not be well captured by standard IQ tests.
