What Was Stephen Hawking's IQ? The 160 Claim vs the Evidence

What was Stephen Hawking's IQ?

Search for Hawking's IQ and you will see 160 stated as if it were fact. Some pages go further and claim he gave the number himself. Neither is true. We could find no test record, no published study estimating his IQ and no interview in which he named a score.

What we do have is his own answer to the question. In a 2004 interview with The New York Times Magazine, Deborah Solomon asked him directly: "What is your I.Q.?" Hawking replied: "I have no idea. People who boast about their I.Q. are losers."

So any honest answer has two parts. First, his IQ is unknown. Second, his recorded achievements tell us far more about his mind than a single test score could.

Where does the "160" figure come from?

The number 160 appears to be borrowed rather than measured. It is the same figure that popular lists give Albert Einstein, who also never took an IQ test, and the two names are usually listed side by side. That looks like a convenient round number for "genius" attached to famous scientists — but this is our inference, not a documented origin.

Real attempts to estimate the IQs of historical figures do exist. In 1926, psychologist Catharine Cox estimated the childhood IQs of about 300 eminent people from their biographies. But her study covered people born between 1450 and 1850 — Hawking was born in 1942, so he could not have been in it. No similar study of Hawking has been published.

What Hawking said about IQ

The full exchange from the 2004 interview is more revealing than the famous one-liner. Asked how we can know whether he qualifies as a genius, Hawking pushed back on the idea of a clear category of geniuses at all:

The media need superheroes in science just as in every sphere of life, but there is really a continuous range of abilities with no clear dividing line.— Stephen Hawking, The New York Times Magazine, 12 December 2004

Pressed on whether he was saying he was not a genius, he answered: "I hope I'm near the upper end of the range." It is a careful, modest view — and it matches how psychologists actually think about intelligence: as a continuous scale, not a club with a membership score.

What would an IQ of 160 actually mean?

Even as a hypothetical, 160 is often misunderstood. Modern IQ tests are scaled so the average is 100 and the standard deviation is 15. On that scale, a score of 160 is four standard deviations above average — roughly 1 person in 31,574.

Some popular pages get these numbers badly wrong. One claims that scores above 145 occur in about "1 in 1,000,000" people; the correct figure is about 1 in 741.

The same number can also mean different things on different tests. Older versions of the Stanford-Binet used a standard deviation of 16, on which 160 is about 1 in 11,000. And most adult tests are not designed to measure precisely at that extreme: very few people score there, so the test has little data to work with. That is one more reason a single "160" says less than it seems.

Hawking's record: from the middle of the class to the Lucasian chair

Hawking was not an obvious prodigy. His official biography says he was "never more than halfway up the class" at St Albans School — although his classmates nicknamed him "Einstein". At Oxford he later estimated he studied only about a thousand hours in three years, and his final result was borderline enough to need an oral exam before he was awarded a first-class degree in 1962.

• 1966: PhD at Cambridge with the thesis "Properties of Expanding Universes".
• 1970: with Roger Penrose, showed that the universe must have begun in a singularity if general relativity is correct.
• 1974: published "Black hole explosions?" in Nature, predicting that black holes emit radiation — now called Hawking radiation.
• 1974: elected a Fellow of the Royal Society at 32, one of the youngest ever.
• 1979 to 2009: Lucasian Professor of Mathematics at Cambridge, the chair once held by Isaac Newton.
• 1988: A Brief History of Time, which has sold more than 20 million copies according to his estate's official site.

He never won a Nobel Prize, because Hawking radiation has not yet been confirmed by experiment. But his work reshaped how physicists think about black holes, quantum theory and the origin of the universe.

Did ALS affect Stephen Hawking's intelligence?

Hawking was diagnosed with motor neurone disease, also known as ALS, in 1963 at the age of 21 and was given about two years to live. He lived another 55 years. His form of the disease was unusually slow-progressing, and over time he lost nearly all movement and his natural voice.

It is often said that ALS "leaves the mind untouched". Research shows it is more complicated. In a study of 279 people with ALS, about half showed some cognitive impairment, mostly mild changes in planning and memory, and about 15% met the criteria for frontotemporal dementia (Ringholz and colleagues, 2005). A 2021 review put cognitive change at up to 65% of patients.

No published assessment of Hawking's own cognition exists. But his continuous output of papers and books until his death in 2018 is strong evidence that his reasoning remained intact — which, given the research, makes his case even more remarkable.

Stephen Hawking vs Albert Einstein vs Elon Musk

Comparisons like these are popular, but there are no real scores to compare. Here is what is actually known.

Does IQ explain Hawking's achievements?

Only partly. Psychologist Dean Keith Simonton, who reviewed decades of research estimating the intelligence of eminent people from historical records, found that estimated intelligence is related to eminence — but only modestly (Simonton, 2009). That leaves most of the difference in eminence explained by other things: creativity, persistence, training, collaboration and opportunity.

Hawking's story fits that picture. A middling school record, a borderline final exam and a devastating diagnosis would not have predicted his career. What set him apart was not a measured number but what he did over five decades.

Sources

• Solomon, D. (2004). The Science of Second-Guessing: Questions for Stephen Hawking. The New York Times Magazine, 12 December 2004.
• Hawking, S. W. (1974). Black hole explosions? Nature, 248, 30–31. https://doi.org/10.1038/248030a0
• Hawking, S. W. (1966). Properties of Expanding Universes (PhD thesis). University of Cambridge. https://doi.org/10.17863/CAM.11283
• Carr, B. J., et al. (2019). Stephen William Hawking CH CBE. 8 January 1942 — 14 March 2018. Biographical Memoirs of Fellows of the Royal Society, 66, 267–308. https://doi.org/10.1098/rsbm.2019.0001
• The official Stephen Hawking biography, hawking.org.uk.
• University of Cambridge: Professor Stephen Hawking (cam.ac.uk/stephenhawking).
• Ringholz, G. M., et al. (2005). Prevalence and patterns of cognitive impairment in sporadic ALS. Neurology, 65(4), 586–590. https://doi.org/10.1212/01.wnl.0000172911.39167.b6
• Rusina, R., Vandenberghe, R., & Bruffaerts, R. (2021). Cognitive and Behavioral Manifestations in ALS: Beyond Motor System Involvement. Diagnostics, 11(4), 624. https://doi.org/10.3390/diagnostics11040624
• Simonton, D. K. (2009). The "Other IQ": Historiometric assessments of intelligence and related constructs. Review of General Psychology, 13(4), 315–326. https://doi.org/10.1037/a0017141
• Cox, C. M. (1926). Genetic Studies of Genius, Vol. II: The Early Mental Traits of Three Hundred Geniuses. Stanford University Press.