In c.1933, Richard Feynman, aged 17, at Far Rockaway High School, New York, to a standardized IQ test, scoring between 120 and 125, as has been reported by his sister and himself, at various times; as shown below:
- “He had a normal IQ. I snuck off, one day, and got into the files and looked up our IQs. Mine was 124, his was 123. So, I was actually smarter than he was.”
- — Joan Feynman (c.1942), Publication; cited by Christopher Sykes (1994) in No Ordinary Genius (pg. 25) 
- “My IQ in high school was tested at 125.”
- — Richard Feynman (1966), “Address to Far Rockaway High School Audience”
- “I may have an IQ of 120, but it's all aimed at physics.”
- — Richard Feynman (1977), as recalled by Murray Gell-Mann’s graduate student Christopher Hill 
In 1939, Feynman, age 21, as an MIT senior, had the highest score in the nation on the Putnam.
In 1941, Feynman, age 23, was said to have had a physics prowess power as comparable to Einstein and Lev Landau.
In 1979, Feynman was named, by Omni magazine, as the "smartest man in the world".
Feynman, currently, is ranked as follows: (IQ:185|#48) (RGM:79|1,350+). In other words, his "real IQ", gauged in retrospect, via per review and meta-analysis, in comparison with all geniuses and top minds, of all time, defines his IQ or "intellectual brightness" (Cox, 1926), as "185", not "125" (age 15).
IQ 125 trope?
The following is an example of how the Feynman "elementary school IQ" of 125 often tends to be employed as a trope or meme of sorts:
Here, supposedly, if we are reading this message correctly, a person can have a "just above average" level of intelligence, i.e. IQ of 125, yet teach one's self calculus, which fewer than 2 percent of the world even understand? In other words, what a person scores on some test in elementary school or high school does not defined their intelligence or IQ or what these become in adulthood. Moreover, Feynman was known to only be mediocre in history English, spelling, and frequently made grammatical errors in his notebooks. In other words, when Feynman was tested, say age 10 to 15, he probably didn't care much for the subjects, as he found them boring. Hence, if he was asked a question such as: "who was the fifth queen of England"? he probably didn't know the answer, because he wasn't interested in this subject, and thus received an IQ of 123 score. The problem, which is inherent in the concept of IQ itself, is that people, such as the person who made the above image, believes that Feynman's IQ is set in stone at 123 (or 125), and that this value is (a) "verified" and (b) holds throughout his existence, as his defining value, which is incorrect. Moreover, some like to use this value to boast that they are smarter than Feynman, which again is incorrect logic.
As to why Feynman would frequently boast that is IQ was 120 or tell a high school audience that his 125, we can only conjecture? Possibly, in respect to the high school kid, barring a reading of the full transcript, that he was trying to say something like "hey, you don't have to have a high IQ to do great thing", or something along these lines? Some have intuited that Feynman, being a notorious joker, was doing a "reverse humble brag" of sort.
Another factor to consider is the so-called "reverse IQ effect", wherein children who when young are told that their IQ is in the "genius range" (140+) or near or above the "ceiling genius range" (210, currently), more often than not (see: Termanites), through some sort of possible reverse psychology, tend to become anonymous over-typical basic career minded types as adults. Whereas others who are told that they are "dunces" as children, e.g. Newton, Maxwell, Einstein, and Edison, e.g. were all labeled or classified as “dunces” in childhood, as adults often tend to rise into the genius range.
In 2013, Edward Wilson (SPE:12|66AE) (Becker 160:73|4L) (Simmons 100:83) (CR:10), the American myrmecologist noted for his "sociobiology" theory (1975), commented about how his IQ was tested at 123, and reflected on this in respect to Feynman's IQ, and things such as: "native intelligence", "genius IQs", "certified geniuses", "extreme brightness", Mensa, and how it the "work" of a person at the frontier that, in reality, defines "genius", not what one's so-called "certified native intelligence" is or was, according to some grade school or high school test:
- “But, you may well ask, isn't the cutting edge a place only for geniuses? No, fortunately. Work accomplished on the frontier defines genius, not just getting there. In fact, both accomplishments along the frontier and the final eureka moment are achieved more by entrepreneurship and hard work than by ‘native intelligence’. This is so much the case that in most fields most of the time, extreme brightness may be a detriment. It has occurred to me, after meeting so many successful researchers in so many disciplines, that the ideal scientist is smart only to an intermediate degree: bright enough to see what can be done but not so bright as to become bored doing it. Two of the most original and influential Nobel Prize winners for whom I have such information, one a molecular biologist and the other a theoretical physicist, scored IQs in the low 120s at the start of their careers. I personally made do with an underwhelming 123. Darwin is thought to have had an IQ of about 130.
- What, then, of certified geniuses whose IQs exceed 140, and are as high as 180 or more? Aren't they the ones who produce the new groundbreaking ideas? I'm sure some do very well in science, but let me suggest that perhaps, instead, many of the IQ-brightest join societies like MENSA and work as auditors and tax consultants. Why should the rule of optimum medium brightness hold? And I admit this perception of mine is only speculative. One reason could be that IQ-geniuses have it too easy in their early training. They don't have to sweat the science courses they take in college. They find little reward in the necessarily tedious chores of data-gathering and analysis. They choose not to take the hard roads to the frontier, over which the rest of us, the lesser intellectual toilers, must travel. Being bright, then, is just not enough for those who dream of success in scientific research.”
- — Edward Wilson (2013), Letters to a Young Scientist (pgs. 78-79) 
Wilson, here, seems seems to give the impression that he believes that he is a "lesser intelligence" and that he was not born "bright", or something along these lines, and that he had to "work" to get to where he is. What we see here, in short, which is possibly what was going through the mind of Feynman, is the difference between a "certified genius with an IQ exceeding 140 or 180 or more", as Wilson phrases things, which are classified as "fake geniuses", technically speaking, and "real geniuses", whose genius level IQs are assigned in retrospect, based on a time-digest weighing of the work they have done, similar the "Cox IQ" method, give or take.
“It’s a likely historical fact that Feynman has once solved an IQ test and the result was 125. There is nothing impossible about it. He found the test stupid, he didn’t care much about the result, he didn’t try hard enough, whatever. The tests aren’t really designed to measure too high IQs too well. Most of those tests didn’t allow results above 150 at all. And even if they allowed these or other high scores, they weren’t terribly good at distinguishing the people. If you define “having some IQ” as getting this result on an IQ test, Feynman had the IQ of 125, I think.
If you want a morally meaningful definition of the IQ, the measure of one’s general mental abilities that sorts the people and reparameterizes the rank so that the currently living people are ordered to a normal distribution centered around 100 with the standard deviation of 15, Feynman almost certainly had a vastly higher IQ, perhaps above 160 and maybe much more than that. The smartest person on earth, whoever he or she is, probably has the IQ between 190 and 200 [see: IQ ceiling].
But this high IQ must be focusing on the mathematical and physics-related abilities, abstract reasoning of this kind, computational skills, and not things like languages. If the languages were the focus, he could have had just 125 if not less than that. Feynman was at most average in foreign languages – although many of us have good enough memory to remember the “Consequentemente, apprendi Portugues” story. ;-)
There are reasons to say that Feynman has belonged to the hundred of smartest people on earth, i.e. the IQ above 180 or so. On the other hand, the legends he liked to spread – that he was basically a genius that randomly emerged in modest conditions, and he’s created that ingenious mind himself, by hard work – are partially true. Since the childhood, Feynman had a very independent, curious approach to questions which was encouraged by his father. He took that approach and because he was vastly smarter than his father, he could achieve impressive things in science. But the attitude – including independence, critical thinking, constant efforts to refuse nonsense (especially reject someone’s efforts for him to fill his mind with nonsense) – have been important. He has focused on physics in a nearly optimal way.
I think that by the 1980s, when theoretical physics moved to things like string theory, his approach to physics was already rather convenient and he couldn’t have possibly belonged among the top 10 powerful minds of that moment. Maybe one could say such things already in the 1970s. But between the 1940s and the 1960s, he simply was a top mind (Feynman was also a Putnam Fellow and had similar clear achievements as a teenager and young man) and any measurement of the IQ that would assign him 125 must be considered silly, even if such an exercise has taken place.”
This is a fairly accurate assessment of things; Feynman probably found the questions on the test boring or stupid, and hence didn't put effort into preparation, say as compared to other children, greased by their parent's gears to score high, so to get into the best college.
- Feynman, Richard. (1994). No Ordinary Genius: the Illustrated Richard Feynman (editor: Christopher Sykes) (IQ, pgs. 25, 29). Norton.
- Brotman, Barbara. (1992). “Genius at Work”, Chicago Tribune, Nov 17.
- Gleick, James. (1992). Genius: The Life and Science of Richard Feynman (IQ, pgs. 30, 448; Landau, pg. 129). Publisher.
- (a) Weigner, Eugene. (1942). Oral Examination of Feynamn's PhD thesis (co-examiner: John Wheeler); Examiners’ report is held in the Mudd Library, Princeton.
(b) Oppenheimer, Robert. (1980). Letters and Recollections (editors: A.K. Smith and C. Weinger) (pg. 269).
(c) Farmelo, Graham. (2009). The Strangest Man: the Hidden Life of Paul Dirac, Mystic of the Atom (pg. 234). Basic Books.
- Smartest Man in the World – Fotuva.org.
- Wai, Jonathan. (2011). “A Polymath Physicists on Richard Feynman’s ‘Low’ IQ and Finding Another Einstein: a Conversation with Steve Hsu” (Ѻ), Psychology Today, Dec 26.
- Mislabeled geniuses and IQ tests – Hmolpedia 2020.
- TIL Feynman’s IQ of 125 was probably bogus – r/TodayILearned.
- Anon. (2016). “Richard Feynman’s IQ Score was ‘only’ 125, and He Loved Joking About It” (Ѻ), Forbes, Nov 8.
- Pickover, Clifford. (2009). A Beginner’s Guide to Immortality: Extraordinary People, Alien Brains, and Quantum Resurrection (pg. #). Hachette.
- Edward Wilson – Hmolpedia 2020.
- Wilson, Edward O. (2013). Letters to a Young Scientist (IQ, pg. 79). Liveright.
- Lubos Motl – Hmolpedia 2020.
- Was Richard Feynman’s IQ really 125? (2018) – Quora.
- Thims, Libb. (2016). “Prodigies and Calculus” (YT) (Feynman IQ: 125, forum discussion), Human Chemistry 101, Nov 15.
- Feynman's IQ – Hmolpedia 2020.