What Is a Genius IQ Score? Where the Line Is Drawn and Why It Is Not Fixed

There is no official genius IQ score. No current IQ test defines “genius”: the label comes from Lewis Terman’s 1916 Stanford-Binet table, which called scores above 140 “near genius or genius”, and 140 is still the line most people mean. On the standard scale (mean 100, standard deviation 15), 140 is the 99.6th percentile, about 1 person in 261, and 145, the usual start of “highly gifted”, is about 1 in 741. Tests cannot measure much above 155 to 160 with any precision, and the famous numbers quoted for historical figures are estimates, not test scores. This guide shows where the line is drawn, how rare each score is, where the label came from and why one number cannot make anyone a genius.

• Genius line: none official. 140 by convention (Terman, 1916); 130 on current test labels (Very Superior on the WAIS-IV, Extremely High on the WISC-V); 145 for “highly gifted”.
• Rarity: 130 is about 1 in 44, 140 about 1 in 261, 145 about 1 in 741 and 160 about 1 in 31,600.
• Ceiling: the Wechsler scales top out around 155 to 160; beyond that a printed score is false precision.
• Famous scores: Einstein’s 160 is an estimate and Marilyn vos Savant’s 228 is an old ratio-IQ score, not results on a modern test.
• Genius is not a score: Terman followed 1,528 high scorers and none won a Nobel Prize, while two boys he screened out did.

What IQ score is a genius?

There is no agreed number, because genius is a judgement about achievement and creativity, not a band on a test. The scores people attach to the word come from five places, and the table sets them side by side.

Most online lists put the genius line at 140 because of Terman, some use 145 or 150 to keep it rarer, and a few use 130. None is wrong and none is more official than the others. For the labels test by test see IQ classifications, and for the debate over a single cut-off see is 130 IQ a genius score and what genius IQ level means. The Mensa cut-off is covered in Mensa IQ score requirements.

How rare is each genius-range score?

The table counts everyone at or above each score on the standard scale, using the normal curve, and the last column turns the share into a city of one million people.

About 3,800 people in a city of a million score 140 or higher, and about 32 score 160 or higher. Above that the numbers are too small to measure reliably, which is why test publishers report few scores beyond 160 and why high-range claims need care. For the neighbouring bands see an IQ of 125 and is 120 IQ high.

Where did the genius label come from?

From the first American revision of the Binet scale. In 1916 Lewis Terman published a table of IQ classifications that called scores above 140 “near genius or genius”, while describing his own boundary lines as “absolutely arbitrary”. He dropped the word by the 1937 revision and no major test since has used it, but the number stuck. Our guide to an IQ of 140 shows how the label is used today.

Terman then tested the idea. His Genetic Studies of Genius, begun in California in 1921, followed 1,528 high-scoring children whose working cut-off was an IQ of about 140 on the 1916 Stanford-Binet, with 135 accepted for siblings and special cases. The group grew up healthy and well educated, but two boys who were tested and missed the cut, William Shockley and Luis Alvarez, later won the Nobel Prize in Physics, and none of the selected children did. A 2020 simulation found that Terman was unlikely to have picked either man, with a 53% to 83% chance of missing both, mostly because the prize is so rare and the minimum IQ so high (Warne and colleagues, 2020). The lesson is that a cut-off can find high ability without predicting very rare outcomes; the full story is in our guide to an IQ of 135.

Why do scores above 160 look so different?

Because they come from a different system or from no test at all. Older childhood tests used ratio IQ, mental age divided by chronological age times 100, which gives a number above 170 for a seven-year-old answering questions written for a twelve-year-old (12 divided by 7, times 100, is about 171) without that child being as rare as a deviation score would show. Our news piece on deviation IQ versus ratio IQ explains the change.

Modern tests compare people with others of the same age, and the Wechsler scales top out in the region of 155 to 160, because too few people in any norm sample answer every item correctly to say how far above that someone is (see the highest IQ score a test can report and the IQ ceiling effect). Guinness World Records later retired its “highest IQ” category for the same reason: scores at the extreme end are far less reliable than scores near the middle of the curve.

Do famous geniuses have IQ scores?

Mostly not, at least not scores from a test they sat. Isaac Newton and Leonardo da Vinci lived centuries before IQ testing, and no test result is on record for Albert Einstein, so the figures attached to them are retrospective estimates. The best-known source is Catharine Cox’s 1926 study of about 300 eminent historical figures, which rated their childhood IQs from biographical records. Those ratings are judgements about evidence, not test scores.

The famous modern numbers have the same problem. Marilyn vos Savant’s 228 was a ratio score on a childhood Stanford-Binet, William James Sidis’s 250 to 300 was never measured, and the childhood figure sometimes quoted for Terence Tao belongs to the same ratio-IQ era. Our guide to the highest IQ ever recorded traces each number, and our profiles of Albert Einstein, Isaac Newton, Leonardo da Vinci, William James Sidis and Terence Tao show what is and is not known for each.

Is a genius score the same as being a genius?

No. A high score is evidence of strong reasoning on a test; “genius” usually means work that changes a field. The two overlap but do not match. A meta-analysis of longitudinal studies found that IQ correlates .56 with educational attainment, .43 with occupational level and .20 with income (Strenze, 2007), and the Terman group shows how far a very high score can be from a historic discovery. What a score cannot supply is creativity, persistence and opportunity; see IQ and creativity, grit versus IQ and is intelligence limited to IQ.

Can an online test tell you that you are a genius?

Not reliably. A genuine score above 140 needs a norm sample large enough to estimate very rare scores, an individually given test and a trained examiner, and even then the result is a range: every score carries a standard error of 2 to 3 points, and for a high score the true value is expected to sit slightly closer to 100 than the observed one. Most online tests publish no norm sample, so a printed “145” cannot be compared with a clinical report. Our guides to the official IQ test, professional IQ tests and IQ score margin of error show what a real result looks like, and how IQ tests work explains the method.

Quick answers about a genius IQ score

• What IQ is a genius? There is no official score. 140 is the usual convention, from Terman’s 1916 table.
• Is 130 IQ a genius? It is the top 2% and the start of the gifted range, but it is not usually called genius.
• Is 140 IQ a genius? It is the usual line: about 1 person in 261.
• Is 160 IQ a genius? It is about 1 in 31,600 and sits at the edge of what tests can measure.
• What is the highest IQ ever recorded? No verified record exists; the famous figures are old ratio scores or estimates.
• Do geniuses have high IQs? Often, but a high score does not make a genius, and many high scorers are not famous for any discovery.

Sources

• Warne, R.T., Larsen, R.A. and Clark, J. (2020): Low base rates and a high IQ selection threshold prevented Terman from identifying future Nobelists, Intelligence, 82, 101488.
• Strenze, T. (2007): Intelligence and socioeconomic success: a meta-analytic review of longitudinal research, Intelligence, 35(5), 401-426.
• Terman, L.M. (1916), The Measurement of Intelligence, Houghton Mifflin, p. 79 (classification of IQs).
• Cox, C.M. (1926), The Early Mental Traits of Three Hundred Geniuses, Stanford University Press (Genetic Studies of Genius, vol. 2).
• Gagné, F. (2021), Differentiating Giftedness from Talent: The DMGT Perspective on Talent Development, Routledge.
• Rarity figures are computed from the normal distribution. The labels by test are those in our guides to IQ classifications, the Stanford-Binet and WISC-V scores.