What Does an IQ of 140 Mean?

An IQ of 140 is at the 99.62nd percentile: it is higher than about 99.62% of people of the same age, and about 1 in 261 people scores 140 or higher. On the WAIS-IV it is classed as Very Superior. Like every IQ score it is an estimate with a margin of error of several points, and it predicts outcomes only on average.

IQ 140 percentile and how it is calculated

IQ tests are scaled so that scores follow an approximately normal distribution with a mean of 100 and a standard deviation (SD) of 15. A score of 140 is 2.67 standard deviations above the mean (z = +2.667). Plugging that into the normal cumulative distribution function gives a percentile of 99.62. Put simply: in a representative group of 1,000 people of your age, about 4 would score 140 or higher.

Some reports use a slightly different convention — for example the percentage of people scoring strictly below 140, or a value read from the test’s own norm tables rather than the ideal curve — so you may see a percentile a fraction of a point different. The full list for every score from 55 to 160 is in our IQ percentile chart.

How 140 compares with nearby scores

Is 140 a good IQ score?

Yes — 140 is exceptionally high, about 1 in 260 people. See also what counts as a good IQ score.

How rare is a 140 IQ?

On the normal model, about 1 in 261 people scores 140 or higher. That is about 3,830 per million people, or roughly 191,500 people in a country of 50 million. Rarity grows quickly in the tails: each extra 5 points above 100 multiplies the rarity, which is why the step from 140 to 145 (1 in 261 → 1 in 741) is much bigger than the step from 135 to 140.

140 IQ classification

Different tests use different descriptive words for the same number. For a full-scale score of 140:

These labels describe where a score falls relative to peers; they are not diagnoses. Newer reports, such as the WAIS-5 sample report, use plainer wording (“Average”, “Above average”, “Very high”). See all bands in IQ score ranges and classification.

What an IQ of 140 means in practice

140 is about 2.67 standard deviations above the mean, at the 99.6th percentile: roughly one person in 260 scores this high. Terman (1916) labelled scores above 140 on his original Stanford-Binet as “near genius or genius”, a label modern psychologists no longer use because it confuses a test score with achievement.

A 140 is high enough that test ceilings start to matter. If a child answers nearly every item correctly on several subtests, the composite may underestimate ability; that is why some gifted-assessment specialists use extended norms (such as the extended norms Pearson has published for the WISC) or above-level achievement tests to differentiate among very high scorers.

It is also worth knowing that early-childhood scores this high are less stable than adult scores. Regression to the mean means a child who scores 140 at age 6 will, on average, score somewhat lower on re-test years later, even though they remain well above average.

140 IQ jobs, education and life outcomes: what research says

Large meta-analyses agree that IQ predicts educational and occupational outcomes on average, with plenty of individual exceptions. Strenze (2007), pooling longitudinal studies, found corrected correlations of about .56 between intelligence and education, .43 with occupational level and .20 with income. For job performance, Schmidt and Hunter (1998) estimated a validity of about .51 for general mental ability; a 2022 re-analysis by Sackett and colleagues revised it to about .31, still useful but leaving most differences in performance to other factors such as experience, conscientiousness and job knowledge.

How does 140 look against real occupations? The table uses Wolfram’s (2023) estimates from the UK Understanding Society survey and assumes a typical spread of about 13 points inside each occupation (the study found only about a quarter of IQ variance lies between occupations). It shows how many people in each group would be expected to score below 140 — a reminder of how much occupations overlap.

Read more in average IQ by occupation. These are group estimates from a short test battery, not entry requirements.

Measurement error: how precise is a score of 140?

A full-length clinical test such as the WAIS-IV or WAIS-5 has very high reliability (internal consistency around .97–.98 for the full-scale IQ), which still leaves a standard error of measurement (SEM) of about 2–3 points; Pearson’s WAIS-5 sample report lists an FSIQ SEM of 3.00. A 95% confidence interval is roughly ±1.96 SEM, so a measured 140 is best read as about 134 to 146. Shorter tests have larger errors (SEM 4–5 or more), widening the band to roughly 131–149.

Extreme scores also tend to move toward the mean on re-testing (regression to the mean). With a reliability of .96, the best estimate of the “true” score behind an observed 140 is about 138.4, which is why many reports centre the confidence interval slightly below the obtained score.

What an IQ of 140 does not tell you

• It cannot be compared across very different tests or eras without adjusting for norms.
• It does not measure creativity, practical wisdom, emotional skills, motivation or character.
• It is a sample of performance on one day; sleep, stress, language and familiarity with tests all affect it.
• Index scores (verbal, spatial, reasoning, memory, speed) can differ widely behind the same full-scale number.
• It does not fix the future: correlations of .2 to .6 leave room for very different outcomes among people with the same score.

The Flynn effect and old norms

A score of 140 also depends on when the test was normed. During the 20th century, average performance on IQ tests rose by about 3 points per decade (Pietschnig & Voracek, 2015; Trahan et al., 2014), so publishers periodically re-norm. Using norms that are 20 years out of date could add roughly 6 points, turning a current-norm 134 into a reported 140.

Online IQ tests and a score of 140

Most online IQ tests are not normed on a representative sample, are taken unsupervised, often have no time control and are completed by a self-selected audience. Many also inflate results to encourage sharing or paid certificates. Treat an online 140 as a rough hint at best; see how accurate online IQ tests are.

How to get a proper IQ assessment

A valid IQ score comes from an individually administered, standardized test (for example the WAIS-5/WAIS-IV for adults, WISC-V for children, or Stanford-Binet 5) given by a licensed or registered psychologist. Expect 60–120 minutes of testing, a written report with index scores and confidence intervals, and a fee that varies by country and provider. Schools, university disability services, and clinical or neuropsychology services can refer you. Ask which test and which norms were used, and for the confidence interval, not just the single number.