IQ 150

150 sits 5 points past the three standard deviation mark and 10 below 160, where most tests top out. You would outscore 99.96% of people.

The Triple Nine Society's top 0.1% line is about 146 on this scale, and 150 clears it. As with any society, membership needs a supervised test, not an online result.

A very high score is not a forecast. Eminence depends on years of work, opportunity, collaborators and luck as much as on ability.

People who score around 150, and the teachers who work with them, often describe some of the following. Treat it as a set of possibilities, not a profile:

• It can be hard to judge what is obvious to other people, so explaining clearly takes practice.
• Perfectionism and overthinking come up often in first-hand accounts.
• None of this is guaranteed. Many people at this level feel ordinary most of the time.

To check a score of 150, a test would need plenty of people at that level in its norm group. With a typical 2,200-person sample, it would expect less than one. That is why scores this high carry more uncertainty.

Ceiling effects set in when a test runs out of hard questions. Strong test-takers then bunch at the top and the score stops separating them.

Scale matters too. If your 150 was reported on an SD 24 scale, it is about 131 on the usual SD 15 scale, and on an SD 16 scale about 147.

On a bell curve with a mean of 100 and a standard deviation of 15, about 0.043% of people score 150 or higher. Applied to whole populations:

Compare the neighbours: 145 or higher is about 1 in 741, 150 or higher is 1 in 2,330, and 155 or higher is 1 in 8,137. Each point up here adds roughly 27% to the rarity.

What your 150 could really be. Treat any single score as the centre of a range. For a good supervised test, about 5 points either side is typical, so 150 really means somewhere from 145 to 155. Online tests are less precise than that.

Which scale was it on? Score reports do not always say. On the common SD 15 scale your 150 stands as it is. If the report used SD 16 it equals about 147, and if it used SD 24 about 131. The percentile follows the converted number.

Scientists, composers and philosophers often receive estimates in this range. These sit near 150. Every figure below is a retrospective estimate, not a measured score. Open a profile to see the evidence and how confident anyone can be.

Rough benchmarks from our profiles that sit within a few points of 150. Degree and university figures are estimates derived from admissions-test averages, not measured IQs.

150 is 3.33 standard deviations above the mean, about 1 in 2,330 people. In a city of 500,000 the bell curve expects about 215 people this high or higher.

Catharine Cox's 1926 study estimated IQs for 301 eminent historical figures from biographical records, and many of her estimates sat around or above this level. Those are retrospective estimates, not test scores. Public IQ claims about famous people are usually of this kind.

How 150 stacks up against the scores just around it and the round numbers people usually ask about. Each score links to its own page.

People with an IQ of 150 typically score about 1590 on the SAT and about 35 on the ACT composite. Scores vary a lot from person to person, so the range shows where about four in five land.