IQ 191
Profoundly Gifted
Quick answer
Yes, and it is extremely rare. An IQ of 191 is higher than all but about 1 in 1.5 billion people.
That is 31 points beyond the ceiling most major tests publish, so the number itself is less certain than its rarity suggests.
Not sure your number is right? Take the free IQ test and compare.
Where 191 falls on the bell curve
191 is plotted on a curve stretched to 200. The tail to its right is real but far too thin to see, which is the visual version of 1 in 1.5 billion.
IQ 191: beyond what most tests can measure
191 is 6.07 standard deviations above the mean. On a bell curve that works out to about 1 in 1.5 billion people, which would mean fewer than one (0.04 expected) in the UK and about 5 worldwide. The bell curve is a model, though, and at this height it is doing most of the work.
No test has enough people in its norm sample to check its accuracy at 191. In a 2,200-person sample the bell curve expects effectively nobody at 191 or higher.
None of this means nobody is this able. It means a single number is not a reliable way to describe them.
How claims like "191 IQ" arise
Most very high numbers you see online come from one of a few sources, and knowing which one produced a 191 tells you how much weight to put on it.
- Different scales. Some tests use a standard deviation of 24, so a 191 there is about 157 on the usual SD 15 scale.
- Historiometric estimates. Researchers such as Catharine Cox (1926) estimated IQs for famous people from biographies. Some of her adjusted estimates went above 200. They are educated guesses, not test results.
- Unnormed online quizzes. A test with no norm data can print any number. Very high outputs usually say more about the scoring than the person.
Famous estimates: Newton, da Vinci and the 160+ club
Nobody in history has a measured IQ of 191. The highest estimates on this site, for figures such as Isaac Newton and Leonardo da Vinci, come from reading their work and lives, not from tests. 37 profiles here are estimated at 160 or more.
Two people with identical estimates can have very different evidence behind them. Each profile explains what its estimate is based on and how confident anyone can be.
How many people have an IQ of 191 or higher?
If IQ follows the standard bell curve, 0.000000066% of people score 191 or higher. Here is what that share means across whole populations:
| Where | Population | IQ 191 or higher |
|---|---|---|
| UK | about 68 million | fewer than one (0.04 expected) |
| US | about 335 million | fewer than one (0.22 expected) |
| World | about 8.1 billion | about 5 |
You would need the whole world to expect about 5 people at 191 or higher.
Exactly 191, counting anyone between 190.5 and 191.5, is about 1 in 3.7 billion. In the US that is fewer than one person, and in the UK fewer than one person.
Treat these as orders of magnitude, not census data. They apply the standard model to everyone, and individual tests have their own norms.
How rare is an IQ of 191?
An IQ of 191 or higher is 7.5 times rarer than 186 or higher, and 196 or higher is 8.4 times rarer again. At this point on the curve, each extra point makes a score about 52% rarer.
What your 191 could really be. Even a good supervised test has a margin of error of roughly 5 points either side, and far more at this height. A true score from 186 to 196 would span rarities from 1 in 200 million to 1 in 13 billion.
Which scale was it on? Score reports do not always say. On the common SD 15 scale your 191 stands as it is. If the report used SD 16 it equals about 185, and if it used SD 24 about 157. The percentile follows the converted number.
Famous people with an estimated IQ near 191
Estimates this high are reserved for a small group of scientists, artists and thinkers. These are the closest to 191. Every figure below is a retrospective estimate, not a measured score. Open a profile to see the evidence and how confident anyone can be.
Fictional characters near 191
Just for fun: the fictional characters whose fan-estimated IQs sit closest to 191.
191 compared with nearby scores
Nearby scores and the round-number landmarks, so you can see how quickly the percentile changes around 191. Every row links to that score's page.
| IQ | Classification | Percentile | Score higher |
|---|---|---|---|
| IQ 10091 lower | Average | 50th | 50% |
| IQ 11081 lower | High Average | 74.8th | 25% |
| IQ 12071 lower | Superior | 90.9th | 9.1% |
| IQ 13061 lower | Gifted | 97.7th | 2.3% |
| IQ 14051 lower | Gifted | 99.62nd | 0.38% |
| IQ 15041 lower | Genius | 99.96th | 0.043% |
| IQ 1865 lower | Profoundly Gifted | 99.9999995th | 0.00000049% |
| IQ 1901 lower | Profoundly Gifted | 99.9999999th | 0.000000099% |
| IQ 1921 higher | Profoundly Gifted | 99.999999956th | 0.000000043% |
| IQ 1965 higher | Profoundly Gifted | 99.9999999921st | 0.0000000078% |
Is 191 a good IQ?
Yes. 191 is far above average, about 1 in 1.5 billion people on the bell curve. At this height, though, tests lose precision, so a single result of 191 is best read as "well above 150" rather than an exact figure you can compare point for point.
What percentile is an IQ of 191?
On the standard scale, 191 lands at about the 99.999999934th percentile: only 0.000000066% of people match or beat it. Percentiles depend on the scale, so check that your score report uses a standard deviation of 15 before comparing it with this page.
Is 191 genius level?
Informally, yes, since 191 is far beyond the 140 to 145 range where popular genius labels begin. But genius in the historical sense means achievement, like Newton's or da Vinci's, and their famous numbers are estimates. No test measures 191 precisely.
What does an IQ of 191 mean?
A 191 means your result on a timed reasoning test was 91 points above the average of 100, which this site labels Profoundly Gifted. Most tests cannot measure this high precisely. It reflects one test on one day, and it does not measure knowledge or character.
How rare is an IQ of 191?
About 1 in 1.5 billion people score 191 or higher. In the UK that is fewer than one person, in the US fewer than one and worldwide about 5. About 1 in 3.7 billion score exactly 191. These are bell curve estimates, not census counts.
What is the mental age for an IQ of 191?
There is no real mental age for adults. The idea comes from early ratio tests for children: a 6-year-old with a ratio IQ of 191 would reason like a typical 11.5-year-old. Today's tests use deviation scores, which rank you against your own age group.