IQ 138: very superior, explained
Yes. An IQ of 138 is in the very superior range, the top 2% or so of the population. It meets the usual entry level for Mensa on a supervised test.
Where 138 sits on the bell curve
An IQ of 138 is 38 points above the average of 100, or 2.53 standard deviations. It is higher than about 99.4% of people of the same age, shown by the shaded area below. Past 130 the curve is almost flat against the axis: only about 2 people in 100 reach this far.
On other IQ scales, the same result would be about 141 on a test with a standard deviation of 16, such as older editions of the Stanford-Binet, and 161 on the Cattell scale, which uses 24. Why scales differ.
IQ 138 meaning: a closer look
With an IQ of 138, you are ahead of roughly 99.4% of people, around one in 177. It sits two points below 140 and eight points above the Mensa level. In a city of one million people, about 5,600 would score 138 or higher. At this height, a single online result is a very rough guide: tests designed for the general population have relatively few hard questions, which limits how precisely they can measure high scores.
GAI or full-scale IQ: which number counts for a bright child?
The WISC-V reports a full-scale IQ, but it can also give a General Ability Index (GAI), which focuses on reasoning and leaves out working memory and processing speed. A 2019 Pearson technical report explains why that matters: gifted children's working memory and speed are usually above average but lower than their reasoning, which can pull the full-scale IQ below a programme's cut-off. The US National Association for Gifted Children recommends accepting the GAI and other reasoning-based indexes as well as the full-scale IQ. Both have an average reliability of 0.96.
Suppose a child scores a full-scale IQ of 138. If their GAI is several points higher, the report is saying that reasoning is a particular strength and that speed or holding information in mind is relatively weaker. Neither number is the "real" IQ: the GAI is a narrower measure of reasoning, while the full-scale IQ includes skills that matter in everyday schoolwork. A large gap is worth discussing with the psychologist, because the same pattern is common in ADHD, autism and learning disorders, which can occur alongside a 138 IQ.
Source: Raiford, Silverman, Gilman and Courville (2019), "WISC-V Technical Report #5: Expanded General Ability Index", NCS Pearson.
What 138 looks like among real people
If you lined up 100 people of your age, about 99 would score lower than 138 and about 1 would score the same or higher. The orange dot marks your place in the line.
In a room of 100 people, typically only about 2 would score 130 or higher.
How precise is a score of 138?
No IQ test measures to the exact point. On a professional test, a result of 138 usually comes with a likely range of about five points either way: 133 to 143. That range runs from the 99th to the 99.7th percentile, all within the very superior range.
Scores this high are rare, so tests have fewer people to compare you with and become less precise. Two good tests can disagree by more than they would near 100.
On the Assessivo test, 138 is the score for 33 correct answers out of 36. How our score is worked out.
So if you scored 138 once, a retest on another day could reasonably land anywhere from 133 to 143. Online tests are less precise still, so treat any online result as a rough estimate.
IQ 138 and mental age in children
Early IQ tests for children worked with a "mental age", the age whose typical performance a child matched. The IQ was that mental age divided by the child's real age, times 100. Turned around, the formula shows what a score of 138 would have meant for children of different ages: working ahead of their years.
| Real age | Mental age at IQ 138 |
|---|---|
| 5 | 6 years 11 months |
| 7 | 9 years 8 months |
| 9 | 12 years 5 months |
| 11 | 15 years 2 months |
| 13 | 17 years 11 months |
The same 138 stands for a gap of about 1 year 11 months at age 5 but 4 years 11 months at 13, because the formula scales with age. That is one reason it broke down for teenagers and adults, whose test performance stops rising every year. Today's tests compare you with people of the same age instead, so a mental age is only a way to picture a child's score, never a description of an adult.
What an IQ of 138 means for you
It sits in the middle of the very superior band, which runs from 130 to 145.
- You likely find abstract reasoning, patterns and complex problems easier than almost everyone around you.
- This is the level many schools and societies use as a benchmark, such as Mensa's top 2%.
- A high score doesn't measure creativity, emotional understanding or persistence, which matter just as much.
How far 138 is from other levels
Famous names reported near 138
Very few famous people have published IQ scores, and most numbers online are invented. These are the ones with a documented report or a published estimate. Each is labelled so you can see what kind of figure it is.
Rated by psychologist Catharine Cox in 1926 from records of his early life: about 135 for childhood (to age 17) and 140 for ages 17 to 26. Estimates like these are rough, and he never took an IQ test.
Published estimate, not a test · Cox, Genetic Studies of Genius, Vol. II (1926)Rated by psychologist Catharine Cox in 1926 from records of his early life: about 135 for childhood (to age 17) and 140 for ages 17 to 26. Estimates like these are rough, and he never took an IQ test.
Published estimate, not a test · Cox, Genetic Studies of Genius, Vol. II (1926)Rated by psychologist Catharine Cox in 1926 from records of his early life: about 135 for childhood (to age 17) and 140 for ages 17 to 26. Estimates like these are rough, and he never took an IQ test.
Published estimate, not a test · Cox, Genetic Studies of Genius, Vol. II (1926)How 138 compares with nearby scores
Want a score that isn't listed, or the share of people between two scores? Try the IQ calculator.
| IQ | Percentile | Classification | Score this high or higher |
|---|---|---|---|
| 128 | 97th | Superior | 1 in 32 |
| 133 | 99th | Very superior | 1 in 72 |
| 138 | 99.4th | Very superior | 1 in 177 |
| 143 | 99.7th | Very superior | 1 in 482 |
| 148 | 99.9th | Very superior | 1 in 1,455 |
Questions about an IQ of 138
What percentile is an IQ of 138?
An IQ of 138 is at about the 99.4th percentile, which means it is higher than about 99.4% of people of the same age.
Is 138 a high IQ?
Yes. 138 is a high IQ by any common definition, in the top one percent of the population.
Can an IQ of 138 get into Mensa?
On most tests, yes. Mensa accepts people who score in the top 2% on an approved, supervised test, which is 130 or above on tests that use a standard deviation of 15. Online test scores are not accepted.
How common is an IQ of 138 or higher?
About 0.56% of people score 138 or higher, roughly 1 in 177. In a stadium of 50,000 people, about 282 would score at this level or above.
What if my child's GAI is higher than their 138 full-scale IQ?
That pattern is common in bright children. The General Ability Index focuses on reasoning, while the full-scale IQ also includes working memory and processing speed, which are often relative weaknesses in gifted children. Many gifted programmes accept either score. Ask the psychologist what the gap means for your child, as it can also point to attention or learning needs.
What mental age is an IQ of 138?
Under the old ratio formula, a 9-year-old with an IQ of 138 would perform like a typical child of about 12 years 5 months, roughly 41 months ahead. The idea only works for children: an adult who scores 138 simply did better than most adults of the same age on the test.
Should I take a professional test with a score of 138?
If you want an official result, for example to join Mensa or for a school programme, yes: only an approved test given under supervision counts. A psychologist can give one, and Mensa runs its own supervised testing sessions.
Is 138 a gifted IQ?
Often, yes. There is no single definition, but 130, two standard deviations above average, is a common benchmark for giftedness. Schools also look at more than one score.
Is an IQ of 138 genius?
No test uses the word genius. In everyday use people usually mean 140 or more, but the label says little: real achievement depends on much more than a score.
Our guide to what counts as a good IQ score covers the high-IQ societies, Mensa IQ requirements lists the qualifying score on each test, and IQ of famous people shows where well-known names really stand. Every score range is in the IQ range chart.
A full IQ score of 138 combines several skills. Our guides explain each one: verbal reasoning, processing speed, fluid vs crystallized intelligence, abstract reasoning and spatial reasoning, or try the free pattern recognition test.
Famous names are often linked to scores like 138, with or without a source. We checked the evidence behind Nikola Tesla's IQ, Stephen Hawking's IQ, Bill Gates' IQ, Elon Musk's IQ, Garry Kasparov's IQ, Terence Tao's IQ, Einstein's IQ and Isaac Newton's IQ.
What would you score?
Take the free Assessivo IQ test: 36 questions, 25 minutes, and your estimated IQ score and percentile as soon as you finish.
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