George BerkeleyPhilosopher
Cox rated him 175 for ages 17 to 26, the same as this page's score. Cox's childhood rating for him was 150.
What does an IQ of 175 mean?
An IQ of 175 is exactly five standard deviations above average, higher than about 99.999971% of people: roughly 1 in 3,488,556. That is the same "five sigma" threshold particle physicists use to announce a discovery. It is also the level mathematician Terence Tao gives as a realistic estimate of his own IQ.
99.999971stpercentile
1 in 3,488,556score 175 or higher
Exceptionally giftedlevel of giftedness
175IQ scoreTop 0.000029%
How far out on the bell curve is 175?
Plot 175 on the bell curve and it lands 5 standard deviations, or 75 points, to the right of the average. The area beyond it, coloured orange below, holds only 0.000029% of people, too thin to see without zooming in.
Five standard deviations: on the whole planet, about 2,350 people would score 175 or higher.
What makes 175 different
In physics, a result is only called a discovery when the chance of seeing it by fluke is below five sigma, about 1 in 3.5 million; the Higgs boson was announced on that standard in 2012. An IQ of 175 sits at precisely the same point on the bell curve. If a random person scored 175, it would be about as surprising as a five-sigma fluke.
Terence Tao, who scored 230 on a childhood ratio test, has said the test is "extremely noisy at these scales" and that "greater than 175" is a more realistic estimate. Among historical figures, Catharine Cox rated the philosopher George Berkeley and the historian Barthold Niebuhr at about 175 for their young adulthood.
How many people have an IQ of 175?
To meet one person scoring 175 or above, you would need, on average, a crowd of 3,488,556. Here is that crowd, built up step by step.
A crowd of 3,488,556 people
3,488,556
Every dot stands for a person. Only the orange one, one in the whole crowd, would be expected to reach 175.
People scoring 175 or higher, by population
| Worldwide (8.2 billion people) | about 2,350 |
| India | about 420 |
| United States | about 98 |
| United Kingdom | about 20 |
| Canada | about 12 |
| Australia | about 8 |
Population: World Bank, total population, 2025. Counts assume the same bell curve in every country and are rounded. Real tests can't sort people this finely, as the next sections explain.
Which high-IQ societies accept an IQ of 175?
Each society below admits a set top slice of the population and lists the score that matches it on the Wechsler adult scale. With a supervised result of 175, you would meet every one of these bars.
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MensaTop 2% (98th percentile) on an approved, supervised test130met
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IntertelTop 1% (99th percentile); lists a Wechsler full-scale IQ of 135135met
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Triple Nine Society99.9th percentile; lists a WAIS full-scale IQ of 146146met
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International Society for Philosophical Enquiry99.9th percentile; lists a WAIS-III or WAIS-IV full-scale IQ of 146146met
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Prometheus Society1 in 30,000 (99.997th percentile), four standard deviations above average160met
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Mega SocietyOne in a million, beyond the range of standard tests171met
Scores for Mensa, Intertel, Triple Nine and ISPE are the Wechsler figures those societies list or that match their percentile. Prometheus and Mega give only a rarity; the scores shown are the matching points on the standard scale. Prometheus says no test currently being given is approved for its entry. Online test results are not accepted by any of them.
Can an IQ test measure 175?
A score of 175 is 15 points past the ceiling of the main clinical tests, which stop at 160. The bars show the highest full-scale result each test can give; only the extended scales, used mainly with exceptionally able children, can report 175.
Behind every score is a norm sample: for the WAIS-IV, 2,200 adults. The bell curve predicts about 0.00063 of them at 175 or above, far less than one person, so no standard test has ever compared anyone with real 175 scorers. Extended norms are built from children who reach the ceiling of the standard test, and their scores rest on that projection.
Add the usual margin of error, about five points either way, and a result of 175 really means somewhere near 170 to 180. Very few people have ever been tested this high, so even extended scales are working near the limit of their evidence. No online test can pin down a score like this, ours included. What online tests can and can't tell you.
Sources: WAIS-IV range and norm sample from Canivez (2010), Mental Measurements Yearbook review; Stanford-Binet 5 and its Extended IQ from PRO-ED; WISC-V extended norms from Pearson Technical Report #6 (2019). Striped bars are extended scales, used only when a person hits the normal ceiling.
Is 175 the same on every IQ scale?
IQ tests don't all use the same yardstick. A scale with a larger standard deviation turns the same rank into a bigger number, especially this far above average.
175standard scale (SD 15), used by Wechsler tests and on this page
180older Stanford-Binet scale (SD 16)
220Cattell scale (SD 24), used by some older and online tests
Turn it around: if a test using the Cattell scale reports 175, the standard-scale equivalent is just 147. From an SD 16 test, 175 converts to about 170. Check the scale before comparing any high score. IQ standard deviations explained.
Historical figures rated at about 175
The figures below are not test scores. In 1926 the psychologist Catharine Cox rated 301 eminent people from records of their youth, giving each a childhood estimate and a second one for ages 17 to 26.
Estimate, not a test
Barthold Georg NiebuhrHistorian
Cox rated him 175 for ages 17 to 26, the same as this page's score. Cox's childhood rating for him was 165.
Source: Cox, C. M. (1926), Genetic Studies of Genius, Vol. II: The Early Mental Traits of Three Hundred Geniuses, Stanford University Press. Cox stressed that thin records pull estimates down. Read more in where the historical genius IQ estimates came from.
Five sigma: the same odds as a physics discovery
"Five-sigma corresponds to a p-value, or probability, of 3x10-7, or about 1 in 3.5 million," as Scientific American explained when CERN announced the Higgs boson. Physicists chose such a strict line because results at three sigma had turned out to be flukes before.
IQ uses the same mathematics. A standard deviation is 15 points, so five of them above the mean of 100 is 175, and the share of a perfect bell curve beyond that point is the same 1 in 3.5 million. The difference is that a physicist can repeat an experiment millions of times, while an IQ test this high has almost no real people to calibrate against.
Sources: Scientific American, "5 sigma, what's that?" (2012); Terence Tao's estimate as quoted in our article on Terence Tao's IQ.
What does an IQ of 175 mean?
A score of 175 means a rank of about one in three and a half million for your age, five standard deviations above the mean. No adult test can measure it, so in practice it is an estimate from an extended scale or a childhood test, carrying a wide margin of error.
Where 175 falls among the levels of giftedness
115–129Mildly gifted
130–144Moderately gifted
145–159Highly gifted
160–179Exceptionally gifted
180+Profoundly gifted
Levels and ranges from Gross, M. U. M. (2000), "Exceptionally and Profoundly Gifted Students: An Underserved Population", Understanding Our Gifted. They are a guide for education, not a ranking of people.
How far 175 is from other milestones
29 points above the Triple Nine and ISPE bar (146)a score of 175 is about 3,776 times rarer than 146
15 points above the ceiling of most professional tests (160)a score of 175 is about 110 times rarer than 160
4 points above the Mega Society's one-in-a-million level (171)a score of 175 is about 3.9 times rarer than 171
5 points below the start of the profoundly gifted band (180)reaching 180 is about 6 times rarer than 175
5 standard deviations above averageaverage is 100 and one standard deviation is 15 points
IQ 175 compared with nearby scores
| IQ | Percentile | Rarity | Level |
|---|---|---|---|
| 171 | 99.99988th | 1 in 905,541 | Exceptionally gifted |
| 173 | 99.999943rd | 1 in 1,762,173 | Exceptionally gifted |
| 175 | 99.999971st | 1 in 3,488,556 | Exceptionally gifted |
| 177 | 99.999985th | 1 in 7,026,047 | Exceptionally gifted |
| 179 | 99.999993rd | 1 in 14,396,452 | Exceptionally gifted |
175 IQ: common questions
Is 175 a high IQ?
Yes. 175 is a very high IQ: about 1 person in 3,488,556 scores this high or higher, which puts it at the 99.999971st percentile. It is above the 130 that most definitions use for a high IQ, and at or above the 146 used by the Triple Nine Society for its 99.9th percentile entry.
Is 175 a genius IQ?
There is no official genius score. Lewis Terman's early Stanford-Binet labels put scores over 140 in a "near genius or genius" group, but modern tests dropped the word. 175 is very rare, yet achievements, not test scores, are what usually earn the word genius.
Can an online IQ test show a score of 175?
Some can show the number, but very few can measure it. Our own test reports up to 145, because a short online test doesn't have enough very hard questions, or enough high scorers in its data, to separate 175 from nearby scores. A supervised Wechsler or Stanford-Binet assessment is needed to confirm it.
What is an IQ of 175 on the Cattell scale?
About 220. The Cattell scale uses a standard deviation of 24 instead of 15, so the same result gives a bigger number. Going the other way, a Cattell score of 175 is only about 147 on the standard scale.
What percentile is an IQ of 175?
An IQ of 175 is at about the 99.999971st percentile. Only about 0.000029% of people score 175 or higher.
How rare is a 175 IQ?
About 1 in 3.5 million on the standard bell curve. 175 is exactly five standard deviations above average, so across 8.2 billion people you would expect only around 2,350 at this level or higher.
Related: what counts as a good IQ score, the highest IQ in the world, famous people's IQs and the full IQ scale and range chart.
Behind a single score of 175 sit several separate abilities. Read about fluid vs crystallized intelligence, abstract reasoning, spatial reasoning, verbal reasoning and processing speed, or try the free pattern recognition test.
Curious which celebrity IQs near 175 hold up? Read the full stories of Terence Tao's IQ, Einstein's IQ, Isaac Newton's IQ, Nikola Tesla's IQ, Stephen Hawking's IQ, Bill Gates' IQ, Elon Musk's IQ and Garry Kasparov's IQ.
Curious where you'd land?
Our free test takes about 25 minutes and gives an estimated IQ with its percentile. Results go up to 145, so a score like 175 can only be confirmed by a psychologist.
Take the free IQ testPortraits are pencil-style sketches by Assessivo, based on: George Berkeley after John Smibert (about 1727), public domain.