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What Does an IQ of 80 Mean?

Scores & Scales

What Does an IQ of 80 Mean? Is It Low, Borderline or Low Average?

An IQ of 80 is the 9th percentile on the standard scale: about 1 person in 11 scores 80 or lower. Major test charts call it the bottom of the Low Average band, and the band just below it is called borderline on some. See what 80 means, how accurate it is and what it predicts.

Bell curve of IQ scores with mean 100 and standard deviation 15, with the area at or below 80 shaded: 9.1 percent of people score 80 or lower, of whom 2.3 percent score below 70 and 6.9 percent score 70 to 79.

An IQ of 80 is the 9th percentile on the standard scale (mean 100, standard deviation 15): about 1 person in 11 scores 80 or lower and 10 in 11 score higher. It is the lowest score in the Low Average band of the Wechsler children’s test (WISC-V), the Stanford-Binet 5 and the Woodcock-Johnson, and it sits one point above the band those charts call Very Low, Borderline or Low. It is not an intellectual disability, which is assessed from a reference point of about 70 plus evidence of difficulty in everyday life, and “dumb” is not a category on any chart. This guide shows where 80 sits on the bell curve, why its label depends on the chart and on the margin of error, what borderline intellectual functioning means, and what a score of 80 does and does not predict.

  • Percentile: 9th (9.1%) on a standard deviation 15 scale; 10.6th on standard deviation 16 and 20.2nd on standard deviation 24 (our normal-curve arithmetic).
  • Rarity: about 1 person in 11 scores 80 or lower, which is 2 or 3 pupils in a class of 30.
  • Label: Low Average (80 to 89) on the WISC-V, the Stanford-Binet 5 and the Woodcock-Johnson; the band just below is called Very Low, Borderline impaired or delayed, or Low, depending on the test.
  • Accuracy: read a reported 80 as roughly 75 to 85, a range that spans two labels.
  • Disability: no. The reference point is about 70, and the US Social Security listing writes in 70 and 75.
  • Prediction: a meta-analysis found IQ correlates .56 with education, .43 with occupation and .20 with income (Strenze, 2007): tendencies in groups, not limits on a person.
Bell curve of IQ scores with mean 100 and standard deviation 15, with the area at or below 80 shaded: 9.1 percent of people score 80 or lower, of whom 2.3 percent score below 70 and 6.9 percent score 70 to 79.
Bell curve of IQ scores with mean 100 and standard deviation 15, with the area at or below 80 shaded: 9.1 percent of people score 80 or lower, of whom 2.3 percent score below 70 and 6.9 percent score 70 to 79.

The figure shades everything below 80: 9.1% of people, of whom 2.3% score under 70 and 6.9% score 70 to 79. Our guides to an IQ of 70 and an IQ of 85 cover the scores either side, and an IQ of 90 covers the band above.

What percentile is an IQ of 80?

On the standard scale an 80 sits 1.33 standard deviations below the average (z = -1.33), which puts it at the 9th percentile. The table places the scores around it on the same curve, and our IQ percentile calculator does the same for any score.

Scores around 80 on the standard scale (mean 100, SD 15, our normal-curve arithmetic)
IQ score Scoring at or below Rarity
70 2.3% 1 in 44
75 4.8% 1 in 21
80 9.1% 1 in 11
85 15.9% 1 in 6.3
90 25.2% 1 in 4.0
100 50.0% 1 in 2.0

The printed number depends on the scale. Most modern tests use a standard deviation of 15, but older Stanford-Binet editions used 16 and the Cattell scales use 24, and the same performance prints as a different number on each. Our explainer on standard deviation 15 versus 16 walks through the arithmetic, and the IQ score converter moves a score between scales. A percentile is a position within a norm sample of people, which is also why parrots have no IQ score; our guide to parrot IQ shows what researchers measure instead.

A printed 80 on three scales (our normal-curve arithmetic)
Scale Percentile of a printed 80 Score at the 9th percentile
Standard deviation 15 (Wechsler, current Stanford-Binet) 9.1% 80.0
Standard deviation 16 (older Stanford-Binet, some school tests) 10.6% 78.7
Standard deviation 24 (Cattell) 20.2% 68.0

Is an IQ of 80 low, borderline or low average?

It depends on the chart, and 80 lands exactly on a label boundary. The table shows where 80 falls on the charts we cover.

Where 80 falls on three common charts
Chart Band that contains 80 Band below it
WISC-V (Wechsler, children) 80 to 89: Low Average 70 to 79: Very Low
Stanford-Binet 5 80 to 89: Low average 70 to 79: Borderline impaired or delayed
Woodcock-Johnson (WJ IV chart) 80 to 89: Low Average 70 to 79: Low

Two things follow. Every chart places 80 above its lowest bands and none calls it a disability category. And because 80 is the first score of its band, a 79 on the same test would print a different word. A one-point gap is smaller than the error in the measurement (see below), so the label a person gets near 80 can come down to chance on the day. Simpler charts, including our own, lump the stretch from 70 to 85 together as borderline to low average. The detailed band tables are in our guides to WISC-V scores, the Stanford-Binet and the Woodcock-Johnson, and the simplified ranges are in IQ ranges and IQ classifications.

What is borderline intellectual functioning?

Borderline intellectual functioning is the term for scores in the stretch just above the intellectual disability range. The DSM-IV-TR defined it as an IQ of 71 to 84. DSM-5 dropped the IQ boundaries, leaving the concept without a clear definition, a change a 2016 paper in BJPsych Bulletin called one of the least highlighted in DSM-5 (Wieland and Zitman). On the normal curve about 13.2% of people score 71 to 84 (our arithmetic, counting each score from its lower edge up to the next whole number), so the old definition covered roughly 1 person in 8, and 80 falls inside it.

It is not a diagnosis of disability. The same authors describe it as a frequently unrecognised condition relevant to the diagnosis and treatment of psychiatric disorders. A 2025 systematic review in Psychiatry Investigation reviewed 45 studies covering 93,396 people with an IQ of 71 to 84 and found higher rates of psychiatric problems, including anxiety, mood, personality and neurodevelopmental disorders, than in average-IQ groups, with outcomes typically between those of average-IQ and mild intellectual disability groups (Cho and colleagues). That is an association across studies, not evidence that a score of 80 causes any outcome. A 2026 paper on disability certification in India adds that people with this profile are often overlooked there because the condition is not recognised as a benchmark disability (Kumar and colleagues), a reminder that the label means different things in different systems.

Is an IQ of 80 an intellectual disability?

No. Intellectual disability is diagnosed from low scores on a standardised test, commonly a reference point of about 70, together with evidence of difficulty in everyday functioning that began in the developmental period. An 80 is about 10 points above that reference, which is more than the roughly 5 points of error either side of a single score. Benefit rules show how fixed the numbers are: the US Social Security listing for intellectual disorder writes in 70, or 71 to 75 with a verbal or performance score of 70 or below, and each sits inside a three-part test (see our news explainer on what the score rules say). An 80 meets neither number. Our guide to low IQ versus learning disability explains why a learning disability is a different thing again, and our guide to an IQ of 70 covers the threshold itself.

How accurate is a score of 80?

Not very, at the level of single points. Every score carries a standard error of measurement, commonly 2 to 3 points on a full-scale adult battery, which gives a 95% interval of about 5 points either side. A reported 80 is best read as 75 to 85. That range crosses the line between the 70 to 79 and 80 to 89 labels, so whether a report prints “Low Average” or the label below it for someone near 80 can come down to chance on the day. Our explainer an IQ score is a range, not a number shows how to read the band, and how to read an IQ test report shows where a real report prints it. A score from an online test depends on how that test was normed, so compare it with a clinical report only with care.

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Take the IIF-certified assessment and get your score with the scale it was measured on, the percentile it corresponds to and the confidence range around it — the three figures most online tests leave out.

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Does the age of the test change a score of 80?

It can. Test norms go out of date because raw performance has risen over the last century. A meta-analysis of 271 samples from 1909 to 2013 estimated gains of 0.28 full-scale IQ points a year, roughly 3 points a decade, and found that the gains have decreased in more recent decades (Pietschnig and Voracek, 2015). As an illustration only, twenty years at 0.28 a year is 5.6 points, which would turn an 80 on stale norms into roughly a 74 on fresh ones and move it from the Low Average band into the one below on the charts above. The real gap depends on the country and the test, and the effect has slowed, so treat the arithmetic as a reason to ask which edition produced a score. Our news piece on why IQ norms expire covers the evidence.

What happens when a score of 80 is retested?

Scores regress toward the average when they are repeated, because part of what put the first score so far below 100 was chance. For two tests on one scale, the expected second score is 100 plus the correlation between the tests times the distance of the first score from 100, which for an 80 is minus 20, twice the pull on a 90. The table applies that formula using correlations reported in studies of how stable cognitive scores are.

Expected next score after an 80 (our arithmetic from the regression formula)
Gap between tests Correlation between scores Expected next score
Age 7 to age 12 .45 91.0
Age 12 to age 16 .59 88.2
Age 16 to age 21 .65 87.0
Adults at age 20, five years apart .76 84.8

These are group averages on an idealised model, not predictions for one person, and an individual’s score can move in either direction. The first three rows come from one study of 11,119 children whose tests changed with age (what 11,119 children show), so a change in the test itself adds to the shift. The adult row is the mean rank-order stability for age 20 and a five-year gap in a meta-analysis of 205 longitudinal studies (Breit and colleagues, 2024). Our page on regression to the mean explains the effect.

What does an IQ of 80 predict?

Test scores predict later outcomes in groups, but loosely. A meta-analysis of longitudinal studies found correlations of .56 with educational attainment, .43 with occupational level and .20 with income (Strenze, 2007). Squared, those figures say how much of the spread in an outcome goes with the score: about 31% for education, 18% for occupation and 4% for income. Most of the variation in how people do sits outside the test, so an 80 shifts the odds and sets no ceiling on an individual.

For the detail behind those numbers, see does IQ predict school success, does IQ predict income and average IQ by education level. For what can and cannot move a score, see can you improve your IQ and does school raise IQ.

Quick answers about an IQ of 80

  • Is an IQ of 80 low? It is below average, at the 9th percentile. The major charts call it Low Average, the first score of that band.
  • Is 80 an intellectual disability? No. The reference point is about 70, and a diagnosis also needs evidence of difficulty in everyday functioning.
  • Is an IQ of 80 borderline? The band just below is called borderline on some charts, and the old DSM-IV-TR definition of borderline intellectual functioning, 71 to 84, includes 80.
  • Is 80 IQ dumb? “Dumb” is not a term any test manual uses. A score describes performance on one test and carries about 5 points of error either side.
  • What percentile is an IQ of 80? The 9th on a standard deviation 15 scale, the 10.6th on standard deviation 16 and the 20.2nd on standard deviation 24.
  • How rare is an IQ of 80? About 1 person in 11 scores 80 or lower.
  • Can someone with an IQ of 80 study, work and drive? A score alone does not decide it. Licences, jobs and courses rest on their own tests and requirements, and an 80 sits well above the levels written into disability rules.

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Parrot IQ

Understanding IQ

Parrot IQ: How Smart Are Parrots Compared With Humans?

Parrots have no IQ score: no validated test gives one. Studies measure single skills instead. Alex, a grey parrot, named the number in sets of up to six items and used none for zero, kea predicted draws from odds, and parrot brains hold about twice as many neurons as primate brains of the same mass.

Bar chart of the number of neurons in the whole brain of five parrot species: Goffin's cockatoo 1.16 billion, grey parrot 1.57 billion, sulphur-crested cockatoo 2.12 billion, kea 2.15 billion and blue-and-yellow macaw 3.14 billion, from a 2016 count by Olkowicz and colleagues, with the human brain at 86 billion for scale.

Parrots do not have an IQ score. No validated intelligence test produces one for any parrot, so a number quoted as a parrot IQ is not a test result. What researchers can measure is a set of separate abilities, and parrots do well on several: a grey parrot named Alex named the number in sets of up to six items and used “none” for zero, kea used the relative numbers of two kinds of item to predict what would be drawn, a cockatoo made and used a tool without being shown how, and companion parrots use human names in ways that look like labels. The brain behind this is small, yet parrots hold on average about twice as many neurons as a primate brain of the same mass. This guide sets out what the studies found, how parrots compare with crows, dogs and humans, and why no test can reduce it to one number.

  • Parrot IQ: none. There is no norm sample and no standard test, so researchers test one skill at a time, usually on a handful of birds.
  • Brain: the grey parrots counted had brains of 8.8 g holding about 1.57 billion neurons, and the largest brain in the parrot sample, a blue-and-yellow macaw’s at 20.7 g, held 3.14 billion (Olkowicz and colleagues, 2016; one or two birds per species).
  • Counting: Alex named the number in sets of up to six items with accuracy above 80% and used “none” for zero (Pepperberg and Gordon, 2005).
  • Reasoning: kea combined relative quantities, a barrier and an experimenter’s biased sampling to predict the outcome of a draw (Bastos and Taylor, 2020).
  • Names: in a 2026 owner survey, 47% of the reports on 884 companion parrots included name use, and some birds used a name for one individual only (Benedict and colleagues).
Bar chart of the number of neurons in the whole brain of five parrot species: Goffin's cockatoo 1.16 billion, grey parrot 1.57 billion, sulphur-crested cockatoo 2.12 billion, kea 2.15 billion and blue-and-yellow macaw 3.14 billion, from a 2016 count by Olkowicz and colleagues, with the human brain at 86 billion for scale.
Bar chart of the number of neurons in the whole brain of five parrot species: Goffin’s cockatoo 1.16 billion, grey parrot 1.57 billion, sulphur-crested cockatoo 2.12 billion, kea 2.15 billion and blue-and-yellow macaw 3.14 billion, from a 2016 count by Olkowicz and colleagues, with the human brain at 86 billion for scale.

Is there a parrot IQ test?

No. An IQ score is a position on a bell curve: a test is given to thousands of people, the results are ranked, and each person’s rank is printed on a scale whose average is 100 (an IQ of 80, for example, is simply the 9th percentile; see what an IQ of 80 means). Nothing like that exists for parrots. There is no standard test, no norm sample and no agreed way to compare a cockatoo with a macaw, so researchers run single experiments, each measuring one narrow skill with a few birds, and report whether the birds beat chance. Our explainer on how IQ tests work shows what a real score needs that a parrot experiment lacks.

The field is growing fast. A 2023 update on parrot cognition counted more than 50 new parrot studies in the four years or so since the previous comprehensive review in 2018, and notes that the field was long pioneered by Irene Pepperberg’s work with Alex, whose name stands for Avian Learning EXperiment. Popular claims that a parrot thinks like a young child borrow the idea of mental age (see IQ and mental age), but the published claims are narrower and tied to single skills, as the sections below show.

How big is a parrot’s brain, and what does it hold?

Small, but densely packed. A 2016 count in PNAS used the isotropic fractionator method to count the cells in the brains of 11 parrot species, 13 songbird species and 4 other bird species. Across the parrots, body mass ranged from 23 to 1,008 grams, brain mass from 1.15 to 20.73 grams and the number of neurons in the brain from 227 million to 3.14 billion. The authors found that songbirds and parrots hold about twice as many neurons as primate brains of the same mass, and that parrots and corvids keep an unusually large share of their neurons in the pallium, the forebrain region that does the work the cerebral cortex does in mammals.

Brains of five parrot species (Olkowicz and colleagues, 2016; one or two birds per species)
Parrot Brain mass Neurons in the whole brain
Goffin’s cockatoo 8.3 g 1.16 billion
Grey parrot 8.8 g 1.57 billion
Sulphur-crested cockatoo 10.1 g 2.12 billion
Kea 13.6 g 2.15 billion
Blue-and-yellow macaw 20.7 g 3.14 billion

Read the table with care, because each figure comes from one or two birds. Against the human brain, which holds about 86 billion neurons (the average used in our guide to elephant IQ), a grey parrot holds about 1.8%, or roughly 1 neuron for every 55. The authors’ point is not that parrots match us. It is that a brain of under ten grams can hold as many neurons as a much larger primate brain: large-brained parrots and corvids have forebrain neuron counts equal to or greater than primates with much larger brains. They suggest that these numbers, packed at high density into the forebrain, contribute substantially to the neural basis of avian intelligence.

The insult “bird brain” is therefore out of date. In 2005 an international consortium of neuroscientists proposed replacing the 100-year-old terminology for the bird cerebrum, because the avian pallium has neocortex-like cognitive functions that the old names hid (Jarvis and colleagues). Our guide to crow IQ covers the other bird group the 2016 paper singles out.

Can parrots count?

One grey parrot could, within limits. Alex was trained to name how many items were in a set, and a 2005 study in the Journal of Comparative Psychology tested whether he understood those answers as numbers rather than as sounds. Without extra training he was asked questions such as “What color?” or “What object?” about a stated number of items in a collection shown all at once, for example subsets of 4, 5 and 6 blocks in three colours, or subsets of 2, 4 and 6 keys, corks and sticks. His accuracy was above 80% and was not affected by the quantity, the mass or the outline of the array. He also used “none” to describe the absence of items, which the authors call a zero-like concept.

A 2006 review by the same researcher adds that he could sum small quantities and concludes that his sense of number compares favourably with that of chimpanzees and young human children. Two cautions follow. The results come from one bird in a long research programme, and they cover sets of up to six, so they show what a grey parrot can learn with training, not what a typical parrot does. They also use spoken English labels, which makes the test closer to a human number test than most animal studies, and that is part of why the result is quoted so often. Our guide to chimpanzee IQ sets out the ape results the review compares with.

Do parrots understand words, or only repeat them?

Mimicry alone does not explain Alex, because the 2005 test asked questions he had not been drilled on and he answered them correctly. For companion parrots the evidence is looser but broader. In a 2026 study in PLOS One, researchers surveyed owners about the words and phrases their birds use. Of the reports on 884 birds, 47% included examples of name use, and those 413 parrots spoke 802 phrases that included names. For a subset the owners gave context: reports on 88 birds of 30 species suggested that parrots applied names appropriately as vocal labels for people and animals, and in some birds the evidence was strong that a name was used for one individual only, not as a category label.

The same paper warns against reading too much into this. Many parrots also used names outside human convention, such as calling their own name to get attention, and the data are owner reports, not controlled tests. A 2025 study in Cognitive Science looked at the other side of language, mistakes. When a grey parrot called Apollo used the word “ball” for a bead, his word choices followed the pattern a model of toddlers’ overextension predicted better than models based on word frequency or sound similarity, using more than 200 pairs of objects and utterances from his YouTube channel. Both studies treat parrot speech as something to model rather than a trick. For wild elephants that appear to address each other with name-like calls, see elephant IQ.

Do parrots use tools and solve problems?

Some do, and at least one cockatoo did it without a lesson. A 2012 report in Current Biology described spontaneous innovation in tool manufacture and use in a Goffin’s cockatoo. The 2023 update counts four new spontaneous innovations described in parrots over the previous four years. It also describes how often the simplest test is passed: as of the earlier review it builds on, string-pulling, in which a bird reels in food hanging from a string, was the task used with the largest number of parrot species, and parrots were generally successful at the basic version, though results were mixed on control versions that check whether the bird understands what it is doing. A pass on the basic task is not, on its own, proof of insight.

Reasoning is harder to show, and kea provide the strongest case. In a 2020 study in Nature Communications, kea were tested on whether they could use the relative numbers of two kinds of item to predict the outcome of a draw, and then combine that with the presence of a barrier and with an experimenter’s biased sampling. They showed three signatures of statistical inference. The authors read this as evidence that true statistical inference is found outside the great apes, and that parts of domain-general thinking can evolve in brains built very differently from ours.

Your own number

Where would your own score land?

Take the IIF-certified assessment and get your score with the scale it was measured on, the percentile it corresponds to and the confidence range around it — the three figures most online tests leave out.

Find your IQ score now! →

Secure & encryptedInstant results10–20 minutes

Do parrots keep a beat?

One cockatoo did. A 2009 study in Current Biology played a sulphur-crested cockatoo a musical excerpt whose tempo was changed across a wide range. The bird spontaneously adjusted the tempo of its rhythmic movements to stay in sync with the beat, which the authors took as evidence that synchronising to a beat is not uniquely human. They link the skill to vocal learning, the ability to copy complex sounds: the hypothesis predicts that only vocal learners, such as humans and some birds, can do it. It is one animal, so it shows what is possible rather than a species norm, but it shows why parrot research looks beyond puzzle boxes.

How do parrots compare with crows, dogs and humans?

There is no common test, so the comparison goes brain cell by brain cell and ability by ability. On brain cells, the 2016 paper puts parrots and corvids together: the raven and the kea have about 1.2 billion neurons in the pallium, more than the pallium of a capuchin monkey, and the blue-and-yellow macaw has about 1.9 billion, more than a rhesus monkey’s. For comparison, the 2017 counts quoted in dog IQ and cat IQ put the cerebral cortex at 627 million neurons in a golden retriever and about 250 million in a domestic cat, so a kea’s pallium holds roughly twice the golden retriever figure (the regions are not defined identically, so treat this as a rough guide).

On ability the pattern is mixed. On counting, the grey parrot’s results are comparable with chimpanzees and young children in the researcher’s own review. On tool innovation a cockatoo joins the crows described in crow IQ. On names, the 2026 evidence is owner reports rather than controlled tests. For the other animals in our series, see dolphin IQ, gorilla IQ and octopus IQ. The honest summary is that parrots belong with the most capable non-human animals, but no study ranks them against one another, and a single number would be invented.

Why do parrot results come from so few birds?

Most parrot experiments test a handful of birds, and the best-known numerical result comes from one. The brain counts above rest on one or two birds per species. That does not make the findings wrong, but it limits how far they stretch: read “grey parrots can count to six” as “one grey parrot, trained in a research programme, did”, and wait for replication in other birds. The 2023 update expects the number of parrot studies to keep rising, so the picture will sharpen.

Quick answers about parrot IQ

  • What is the IQ of a parrot? There is none. No validated test produces a parrot IQ.
  • Which parrot is the smartest? No study ranks species. The grey parrot has the strongest number and language results, mostly from one bird; cockatoos have tool and rhythm results; kea have the inference result.
  • Are parrots smarter than dogs? No study measures that directly. A kea’s pallium holds roughly twice the neurons counted in a golden retriever’s cortex, but dogs have been tested on far more tasks.
  • Are parrots as smart as humans? No test compares them. A grey parrot’s brain holds about 1.8% of the neurons in a human brain.
  • Do parrots understand what they say? Alex answered new questions with words correctly. For pet parrots the evidence is owner reports, which suggest some birds use names as labels.
  • Can a parrot count? One grey parrot named the number in sets of up to six and used “none” for zero.

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What Does an IQ of 90 Mean?

Scores & Scales

What Does an IQ of 90 Mean? Is It Low, Average or Below Average?

An IQ of 90 is the 25th percentile on the standard scale: about 1 person in 4 scores 90 or lower. Major test charts call it the bottom of the Average band, while simpler charts call it low average. See what 90 means, how accurate it is and what it predicts.

Bell curve of IQ scores with mean 100 and standard deviation 15, split at 90 and 110: 25 percent of people score 90 or lower, 50 percent score between 90 and 110 and 25 percent score 110 or higher.

An IQ of 90 is the 25th percentile on the standard scale (mean 100, standard deviation 15): about 1 person in 4 scores 90 or lower and 3 in 4 score higher. It is not a low score. The Wechsler children’s test (WISC-V), the Stanford-Binet 5 and the Woodcock-Johnson all put 90 at the bottom of their Average band, and half of all people score between 90 and 110. It is “below average” only in the literal sense of sitting 10 points under 100, and some simpler charts label the 85 to 99 stretch “low average”. This guide shows where 90 sits on the bell curve, how the labels differ by chart and by scale, how far to trust one score and what a score of 90 does and does not predict.

  • Percentile: 25th (25.2%) on a standard deviation 15 scale; 26.6th on standard deviation 16 and 33.8th on standard deviation 24 (our normal-curve arithmetic).
  • Rarity: not rare. About 1 person in 4 scores 90 or lower, which is 7 or 8 pupils in a class of 30.
  • Label: Average on the WISC-V and Stanford-Binet 5 (90 to 109) and on the Woodcock-Johnson (90 to 110); low average on simpler charts that call 85 to 99 low.
  • Accuracy: read a reported 90 as roughly 85 to 95.
  • Prediction: a meta-analysis found IQ correlates .56 with education, .43 with occupation and .20 with income (Strenze, 2007): tendencies in groups, not limits on a person.
Bell curve of IQ scores with mean 100 and standard deviation 15, split at 90 and 110: 25 percent of people score 90 or lower, 50 percent score between 90 and 110 and 25 percent score 110 or higher.
Bell curve of IQ scores with mean 100 and standard deviation 15, split at 90 and 110: 25 percent of people score 90 or lower, 50 percent score between 90 and 110 and 25 percent score 110 or higher.

The figure shows why 90 matters on the bell curve: the quartile lines fall at 89.9 and 110.1, so 90 is the point where the middle half of the population begins. Our guides to an IQ of 85 and an IQ of 115 cover the scores either side.

What percentile is an IQ of 90?

On the standard scale a 90 sits two thirds of a standard deviation below the average (z = -0.67), which puts it at the 25th percentile. The table places the scores around it on the same curve, and our IQ percentile calculator does the same for any score.

Scores around 90 on the standard scale (mean 100, SD 15, our normal-curve arithmetic)
IQ score Scoring at or below Scoring higher
80 9.1% 90.9%
85 15.9% 84.1%
90 25.2% 74.8%
95 36.9% 63.1%
100 50.0% 50.0%
105 63.1% 36.9%
110 74.8% 25.2%

The printed number depends on the scale. Most modern tests use a standard deviation of 15, but older Stanford-Binet editions used 16 and the Cattell scales use 24, and the same performance prints as a different number on each. Our explainer on standard deviation 15 versus 16 walks through the arithmetic, and the IQ score converter moves a score between scales. A percentile is a position within a norm sample of people, which is also why animals have no IQ score; our guide to elephant IQ shows what researchers measure instead.

A printed 90 on three scales (our normal-curve arithmetic)
Scale Percentile of a printed 90 Score at the 25th percentile
Standard deviation 15 (Wechsler, current Stanford-Binet) 25.2% 89.9
Standard deviation 16 (older Stanford-Binet, some school tests) 26.6% 89.2
Standard deviation 24 (Cattell) 33.8% 83.8

Is an IQ of 90 low, average or below average?

It depends on the chart, so check which chart a label comes from. The table shows where 90 falls on the charts we cover.

Where 90 falls on four common charts
Chart Band that contains 90 Band below it
WISC-V (Wechsler, children) 90 to 109: Average 80 to 89: Low Average
Stanford-Binet 5 90 to 109: Average 80 to 89: Low average
Woodcock-Johnson 90 to 110: Average 80 to 89: Low Average
Our simplified IQ ranges guide 85 to 115: average range, with 85 to 99 called low average 70 to 85: borderline to low average

Three of the four charts call 90 plainly average, and the fourth splits its average range at 100. None of them treats 90 as a concern in itself. The detailed band tables are in our guides to WISC-V scores, the Stanford-Binet and the Woodcock-Johnson, and the simplified ranges are in IQ ranges and IQ classifications.

“Below average” is literally true, because 90 is under 100, and so is the score of half the population. It is also 20 points above the reference point of about 70 used in assessing intellectual disability, a diagnosis that needs evidence of difficulty in everyday functioning as well as a score; our guide to an IQ of 70 explains it.

How accurate is a score of 90?

Not very, at the level of single points. Every score carries a standard error of measurement, commonly 2 to 3 points on a full-scale adult battery, which gives a 95% interval of about 5 points either side. A reported 90 is best read as 85 to 95. That range crosses the line between the 80 to 89 and 90 to 109 labels, so whether a report prints “Low Average” or “Average” for someone near 90 can come down to chance on the day. Our explainer an IQ score is a range, not a number shows how to read the band, and how to read an IQ test report shows where a real report prints it. A score from an online test depends on how that test was normed, so compare it with a clinical report only with care.

Does the age of the test change a score of 90?

It can. Test norms go out of date because raw performance has risen over the last century. A meta-analysis of 271 samples from 1909 to 2013 estimated gains of 0.28 full-scale IQ points a year, roughly 3 points a decade, and found that the gains have decreased in more recent decades (Pietschnig and Voracek, 2015). As an illustration only, twenty years at 0.28 a year is 5.6 points, which would turn a 90 on stale norms into roughly an 84 on fresh ones. The real gap depends on the country and the test, and the effect has slowed, so treat the arithmetic as a reason to ask which edition produced a score. Our news piece on why IQ norms expire covers the evidence.

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What happens when a score of 90 is retested?

Scores regress toward the average when they are repeated, because part of what put the first score below 100 was chance. For two tests on one scale, the expected second score is 100 plus the correlation between the tests times the distance of the first score from 100, which for a 90 is minus 10. The table applies that formula using correlations reported in studies of how stable cognitive scores are.

Expected next score after a 90 (our arithmetic from the regression formula)
Gap between tests Correlation between scores Expected next score
Age 7 to age 12 .45 95.5
Age 12 to age 16 .59 94.1
Age 16 to age 21 .65 93.5
Adults at age 20, five years apart .76 92.4

These are group averages on an idealised model, not predictions for one person, and an individual’s score can move in either direction. The first three rows come from one study of 11,119 children whose tests changed with age (what 11,119 children show), so a change in the test itself adds to the shift. The adult row is the mean rank-order stability for age 20 and a five-year gap in a meta-analysis of 205 longitudinal studies (Breit and colleagues, 2024). Our page on regression to the mean explains the effect.

What does an IQ of 90 predict?

Test scores predict later outcomes in groups, but loosely. A meta-analysis of longitudinal studies found correlations of .56 with educational attainment, .43 with occupational level and .20 with income (Strenze, 2007). Squared, those figures say how much of the spread in an outcome goes with the score: about 31% for education, 18% for occupation and 4% for income. Most of the variation in how people do sits outside the test, so a 90 nudges the odds and sets no ceiling.

For the detail behind those numbers, see does IQ predict school success, does IQ predict income and average IQ by education level. For how a college entrance score maps onto this scale, see SAT score to IQ, and for the average itself see what the average IQ test score is.

Quick answers about an IQ of 90

  • Is an IQ of 90 low? Not on the major charts. It is the 25th percentile and the first score in the Average band on the WISC-V, the Stanford-Binet 5 and the Woodcock-Johnson.
  • Is 90 below average? Literally yes, because it is under 100, and so is the score of half the population.
  • How rare is an IQ of 90? It is not rare: about 1 person in 4 scores 90 or lower.
  • What percentile is 90? The 25th on a standard deviation 15 scale, the 26.6th on standard deviation 16 and the 33.8th on standard deviation 24.
  • Is 90 an intellectual disability? No. The reference point is about 70, and a diagnosis also needs evidence of difficulty in everyday functioning.
  • How accurate is it? Read a reported 90 as roughly 85 to 95.

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Elephant IQ

Understanding IQ

Elephant IQ: How Smart Are Elephants Compared With Humans?

Elephants have no IQ score: no validated test gives one. Studies measure single skills instead. One of three Asian elephants passed the mirror mark test, six waited for a partner before pulling a rope, and wild herds use name-like calls, yet one elephant’s cortex held 5.6 billion neurons, a third of the human count.

Bar charts of neuron counts: the African elephant brain holds 257 billion neurons against 86 billion in the human brain, but the elephant cerebral cortex holds 5.6 billion against 16.3 billion in the human cortex, from a 2014 count by Herculano-Houzel and colleagues.

Elephants do not have an IQ score. No validated intelligence test produces one for elephants, so any number quoted as an elephant IQ is not a test result. What researchers can measure is a set of separate abilities, and the set is impressive: an Asian elephant passed the mirror mark test, elephants waited for a late partner before pulling a rope together, a young male stood on a cube to reach food, and wild African elephants appear to address one another with name-like calls. The brain behind this is the largest on land, yet a count of one African elephant found 5.6 billion neurons in its cerebral cortex, about a third of the human figure. This guide sets out what the studies found, how elephants compare with dogs, dolphins and chimpanzees, and why no test can reduce it to one number.

  • Elephant IQ: none. There is no norm sample and no standard test, so researchers test one skill at a time, usually on a handful of animals.
  • Brain: 257 billion neurons in all, 97.5% of them in the cerebellum, but only 5.6 billion in the cerebral cortex against about 16.3 billion in the human cortex (Herculano-Houzel and colleagues, 2014; one adult male African elephant).
  • Mirror: one of three Asian elephants passed the mark test (Plotnik, de Waal and Reiss, 2006).
  • Cooperation: six elephants waited for a late partner before pulling a rope, on average 93% of the time (Plotnik and colleagues, 2011).
  • Calls: in wild African elephants a call’s sound could be matched to the individual it was addressed to, and elephants answered calls addressed to them differently (Pardo and colleagues, 2024).
Bar charts of neuron counts: the African elephant brain holds 257 billion neurons against 86 billion in the human brain, but the elephant cerebral cortex holds 5.6 billion against 16.3 billion in the human cortex, from a 2014 count by Herculano-Houzel and colleagues.
Bar charts of neuron counts: the African elephant brain holds 257 billion neurons against 86 billion in the human brain, but the elephant cerebral cortex holds 5.6 billion against 16.3 billion in the human cortex, from a 2014 count by Herculano-Houzel and colleagues.

Is there an elephant IQ test?

No. An IQ score is a position on a bell curve: a test is given to thousands of people, the results are ranked, and each person’s rank is printed on a scale whose average is 100 (an IQ of 90, for example, is simply the 25th percentile; see what an IQ of 90 means). Nothing like that exists for elephants. There is no standard test, no norm sample and no agreed way to make an elephant try. Researchers run single experiments, each measuring one narrow skill with a few animals, and report whether they beat chance. Our explainer on how IQ tests work shows what a real score needs that an elephant experiment lacks.

Elephants are also difficult subjects. The authors of a 2011 cooperation study put the shortage of systematic evidence down mainly to the danger and difficulty of testing the largest land animal. The trunk adds a second problem: the team behind a 2011 problem-solving study argued that earlier tool tests may have failed because they asked elephants to hold a stick in the trunk, which interferes with its use as a sensory organ for locating the food. A test designed around a human hand does not suit an animal that explores with its nose. Any figure that circulates as an elephant IQ comes without a test, a sample or a scale, so it cannot be read as a score.

How big is an elephant’s brain, and what does it hold?

Very big, and unevenly organised. A 2014 count in Frontiers in Neuroanatomy measured the brain of one adult male African elephant. It weighed 4,619 grams, about three times the human brain, and held 257 billion neurons, three times the human average of 86 billion. But 97.5% of those neurons, 251 billion, sit in the cerebellum, which the authors suggest might be related to the elephant’s sensorimotor specialisations, such as the trunk.

Elephant and human brains compared (Herculano-Houzel and colleagues, 2014)
Measure African elephant (one adult male) Human (average)
Brain mass 4,619 g about a third as heavy
Neurons in the whole brain 257 billion 86 billion
Neurons in the cerebral cortex 5.6 billion 16.3 billion

The cortex is where the authors look for the difference. The elephant cortex weighs more than twice as much as the human cortex, yet it holds only 5.6 billion neurons, about a third of the human count. They argue that the larger number of cortical neurons in humans, not the size of the whole brain, is what goes with the cognitive edge humans have over elephants and other large-brained mammals. A 2008 review by Hart and colleagues adds that elephant cortical neurons are much less densely packed than in large-brained primates, which the reviewers link to slower, less compartmentalised processing.

Against the other animals in our guides the elephant cortex is large. Its 5.6 billion neurons are about 9 times the 627 million counted in a golden retriever and about 22 times the roughly 250 million in a domestic cat (the 2017 counts quoted in dog IQ and cat IQ). One caution: the elephant figure comes from a single animal, so read it as an estimate for one adult male rather than an average for the species.

Can an elephant recognise itself in a mirror?

One Asian elephant did. In a 2006 study in PNAS, three Asian elephants named Happy, Maxine and Patty were given a large mirror. All three spent far more time near it when it was open than when it was covered (Happy 19.4% of the time against 0.2%, Maxine 37.9% against 1.3%, Patty 49.7% against 3.3%), which shows that the reflection, not the novelty of the equipment, held their interest.

Then came the mark test: a visible mark on one side of the head and an invisible sham mark on the other, so that only sight could tell them apart. Only Happy passed. She repeatedly touched the visible mark and not the sham mark, and did so again while standing directly in front of the mirror. The authors compare the way the elephants’ responses progressed with those of apes and dolphins and suggest convergent cognitive evolution linked to complex sociality and cooperation. Passing is usually read as a sign of self-awareness, but this is one test on one animal out of three, and failing it, as two elephants did, is hard to interpret.

Do elephants cooperate, use tools and solve problems?

Cooperation is the strongest result. In a 2011 study in Thailand, twelve elephants first learned to pull a rope attached to a sliding table that carried food. Six were then tested in pairs on a version where two elephants had to pull the two ends of one rope at the same time to bring the food within reach. When one elephant was released later than its partner, the six waited before pulling between 88% and 97% of the time, a mean of 93%, for delays of up to 45 seconds. They also stopped pulling when the partner had no access to a rope. The authors suggest that elephants may have reached a cooperative skill level on a par with chimpanzees.

Insight has been harder to show. A 2011 paper in PLOS ONE offered three Asian elephants food out of reach overhead. Without prior trial and error, a 7-year-old male moved a large plastic cube and stood on it to get the food, then fetched the cube from different places and, when given smaller objects, tried stacking them. One animal out of three is a thin base. The 2008 review by Hart and colleagues rates elephant performance on tool use, visual discrimination learning and insight tests as unimpressive next to chimpanzees, so the honest picture is mixed, and the stick problem described above may explain part of the gap.

Do elephants have names, and do they understand pointing?

Possibly names, yes. Dolphins and parrots address one another by imitating the addressee’s calls. In a 2024 study in Nature Ecology & Evolution on wild African elephants, researchers used machine learning to show that the receiver of a call could be predicted from the call’s acoustic structure, however similar it was to the receiver’s own voice, and elephants responded differently to playbacks of calls that had been addressed to them than to calls addressed to someone else. The authors read this as individual addressing without imitation, which is why the calls are described as name-like rather than as names.

Pointing is a skill dogs are famous for, and elephants have never been domesticated. A 2013 study found that a group of 11 captive African elephants, seven of them significantly as individuals, could use a human pointing gesture to find hidden food, including when the experimenter’s distance from the hiding place varied and when the gesture was visually subtle (Smet and Byrne). Wild elephants also sort people: family groups in Amboseli National Park, Kenya, became more defensive after playbacks of Maasai voices than after voices of a less threatening group, and responded less to Maasai women and boys (McComb and colleagues, 2014). An earlier study found that elephants tell the two groups apart by scent and by the colour of clothing (Bates and colleagues, 2007).

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Take the IIF-certified assessment and get your score with the scale it was measured on, the percentile it corresponds to and the confidence range around it — the three figures most online tests leave out.

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The main elephant studies at a glance

What each experiment tested and what happened
Study Elephants What was tested What happened
Mirror mark test, 2006 3 Asian Touch a mark visible only in a mirror One of three passed
Rope cooperation, 2011 6 Asian, tested in pairs Pull two ends of one rope together Waited for a late partner 88% to 97% of the time
Cube stacking, 2011 3 Asian Reach food hung overhead A 7-year-old male stood on a cube without trial and error
Pointing, 2013 11 captive African Find hidden food from a pointing gesture Seven were significant as individuals
Human voices, 2014 Family groups in Amboseli Playbacks of Maasai and other voices More defensive after Maasai voices, less after women and boys
Name-like calls, 2024 Wild African Is the receiver predictable from the call Yes, and playbacks addressed to them drew a different response

Do elephants never forget?

The saying is an exaggeration, because nobody has measured “never”, but there is a real finding behind it. The 2008 review by Hart and colleagues concludes that elephants seem to excel in long-term spatial and temporal memory and in social memory, while performing less impressively on tool use, discrimination learning and insight tasks than chimpanzees. It also notes reactions to disabled and dead companions that are mindful of what researchers call theory of mind. Memory is the ability reviewers single out, and it is the one an IQ-style test would measure least well in a wild animal.

How does elephant intelligence compare with dogs, dolphins and chimpanzees?

There is no common test, so the comparison has to go ability by ability. On mirror self-recognition, one elephant joined the apes and dolphins in a 2006 comparison. On cooperation, the 2011 authors place elephants possibly on a par with chimpanzees. On tool use and insight, the 2008 review ranks them below chimpanzees. On cortical neurons, elephants sit between the animals counted in our guides and humans. For the other species, see dog IQ, cat IQ, dolphin IQ, chimpanzee IQ, gorilla IQ, crow IQ and octopus IQ.

Quick answers about elephant IQ

  • What is the IQ of an elephant? There is none. No validated test produces an elephant IQ.
  • Are elephants smarter than dogs? No study measures that directly. An elephant cortex holds about 9 times the neurons counted in a golden retriever, but dogs have been tested on far more tasks.
  • Are elephants as smart as humans? No test compares them. The human cortex holds about 16.3 billion neurons against 5.6 billion in the elephant counted.
  • Can elephants recognise themselves in a mirror? One of three Asian elephants passed the mark test in 2006.
  • Do elephants have names for each other? Wild African elephants appear to use calls addressed to individuals, which researchers call name-like.
  • Do elephants never forget? Reviewers single out long-term spatial and social memory; “never” has not been measured.

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What Does an IQ of 145 Mean?

Scores & Scales

What Does an IQ of 145 Mean? How Rare Is It and Is It Genius?

An IQ of 145 is three standard deviations above average: the 99.87th percentile, roughly 1 person in 741. It is where the Stanford-Binet 5 changes its label to very gifted, but on the Cattell scale the same printed number is only the 97th percentile. See what 145 means, how rare it is and how far to trust one score.

Three grids of 1,000 squares showing how many people score a printed 145 or higher: 1 in 741 on the standard deviation 15 Wechsler scale, 1 in 407 on a standard deviation 16 scale and about 30 in 1,000 on the standard deviation 24 Cattell scale.

An IQ of 145 is three standard deviations above the average of 100 on the standard scale (mean 100, standard deviation 15). That is the 99.87th percentile: about 1 person in 741 scores 145 or higher. The Stanford-Binet 5 labels everything from 145 up “very gifted or highly advanced”, the Wechsler tests put 145 in the same top band as 130, and a printed 145 on the Cattell scale is only the 97th percentile. This guide shows where 145 sits on the bell curve, what the labels mean, how far to trust a single score and what happens when it is retested.

  • Percentile: 99.87th on a standard deviation 15 scale (our normal-curve arithmetic); 99.75th if the 145 was printed on a standard deviation 16 scale; 97.0th on the standard deviation 24 Cattell scale.
  • Rarity: 0.135% of people score 145 or higher, about 1 in 741. Of the world’s roughly 8 billion people, the curve puts about 11 million at 145 or above (model arithmetic, not a head count).
  • Label: Very gifted or highly advanced on the Stanford-Binet 5 (145 to 160); Very Superior on the WAIS-IV and Extremely High on the WISC-V, the same labels those tests use from 130.
  • Precision: with a standard error of 2 to 3 points, a reported 145 fits a true standing of roughly 140 to 150.
  • Evidence behind the number: a Wechsler norm sample of about 2,200 people would contain only about 3 people this high, so the top of the norm table is largely the curve extended.
Three grids of 1,000 squares showing how many people score a printed 145 or higher: 1 in 741 on the standard deviation 15 Wechsler scale, 1 in 407 on a standard deviation 16 scale and about 30 in 1,000 on the standard deviation 24 Cattell scale.
Three grids of 1,000 squares showing how many people score a printed 145 or higher: 1 in 741 on the standard deviation 15 Wechsler scale, 1 in 407 on a standard deviation 16 scale and about 30 in 1,000 on the standard deviation 24 Cattell scale.

To check any score yourself, enter it into our IQ percentile calculator, or turn it into another test’s scale with the IQ score converter. The neighbouring pages in this series are an IQ of 140 and an IQ of 150; for every band at once, read IQ ranges.

How rare is an IQ of 145?

On the standard scale an IQ of 145 is exactly three standard deviations above the mean. On a normal curve that is the 99.865th percentile: 99.865% of the reference sample scored lower and 0.135% scored 145 or higher, one person in 741. The whole 145 to 159 band holds about 0.13% of people (1 in 759), and everything from 160 up about 0.003% (1 in 31,600). Our page on the IQ bell curve shows the shape.

Scores around 145 on the standard scale (mean 100, standard deviation 15)
IQ score Percentile Scoring this high or higher: about 1 in
130 97.7th 44
135 99.0th 102
140 99.6th 261
145 99.87th 741
150 99.96th 2,330
155 99.99th 8,140
160 99.997th 31,600

Read the table as a ladder that narrows fast: each five-point step above 140 makes the score roughly three times rarer (1 in 261, 1 in 741, 1 in 2,330). A 145 is about 2.8 times rarer than a 140 and about 3.1 times more common than a 150. For how this arithmetic is built, see how rare a high IQ score actually is.

Is 145 IQ genius?

There is no official IQ cut-off for genius. The word was attached to scores over 140 in Terman’s 1916 table for the first Stanford-Binet revision, which called them “near genius or genius”, and the habit stuck. No current Wechsler or Stanford-Binet manual defines it. What 145 does earn is a place in the top 0.14%. Françoys Gagné’s model of giftedness defines “highly gifted” as the top 1 in 1,000, and the IQ often quoted for that level is 145, although one in 1,000 on this scale works out at about 146 (our arithmetic).

For the wider question see is 130 IQ genius?, what a genius IQ level is and where celebrity IQ numbers come from.

What is a 145 on other IQ scales?

The standard deviation is a publishing choice, and it changes what a printed 145 means. Wechsler tests and the current Stanford-Binet use 15, older Stanford-Binet forms and several school ability tests use 16, and the Cattell scales use 24.

The same printed 145 on three scales
Scale Standard deviation Percentile of a printed 145 Scoring that high: about 1 in Same standing on the Wechsler scale
Wechsler, current Stanford-Binet 15 99.87th 741 145
Older Stanford-Binet, some school tests 16 99.75th 407 142
Cattell scales 24 97.0th 33 128

A Cattell 145 is therefore about a Wechsler 128, and the Cattell score that matches a Wechsler 145 is 172. It also falls just short of the 148 that matches a Wechsler 130, the Mensa line on that scale. The conversion has two steps: subtract 100, divide by the scale’s standard deviation, then multiply by 15 and add 100. The standard deviation 15 vs 16 explainer walks through the arithmetic, and the Mensa guide applies it to a well-known cut-off.

How accurate is a score of 145?

Not very, at the level of single points. Every score carries a standard error of measurement, commonly 2 to 3 points on a full-scale adult battery, which gives a 95% interval of about 5 points either side. A reported 145 is best read as 140 to 150. The error is no worse at 145 than elsewhere in principle, but the evidence behind the number is thinnest here: a sample of 2,200 people holds about three people this high, and near a test’s ceiling there is less information left to separate people (why test scores stop near 160). Our explainer an IQ score is a range, not a number shows how to read the band, and how to read an IQ test report shows where a real report prints it.

What happens when a 145 is retested?

Scores regress toward the average when they are repeated, because part of what made the first score extreme was chance. For two tests on one scale, the expected second score is 100 plus the correlation between the tests times the distance of the first score from 100. The table applies that formula to a 145 using correlations reported in studies of how stable cognitive scores are.

Expected next score after a 145 (our arithmetic from the regression formula)
Gap between tests Correlation between scores Expected next score
Age 7 to age 12 .45 120
Age 12 to age 16 .59 127
Age 16 to age 21 .65 129
Adults at age 20, five years apart .76 134

These are group averages on an idealised model, not predictions for any one person. The first three rows come from one study of 11,119 children whose tests changed with age, so a change in the test itself adds to the drop (what 11,119 children show). The adult row is the mean rank-order stability for age 20 and a five-year gap in a meta-analysis of 205 longitudinal studies (Breit and colleagues, 2024). A retest a few weeks later on the same test would regress far less, because the correlation is much higher. Our page on regression to the mean explains the effect.

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Where would your own score land?

Take the IIF-certified assessment and get your score with the scale it was measured on, the percentile it corresponds to and the confidence range around it — the three figures most online tests leave out.

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Does 145 qualify for Mensa and other high-IQ societies?

Yes for Mensa, which takes roughly the top 2%, about 130 on a Wechsler scale; a 145 clears that line by 15 points. The Triple Nine Society asks for the 99.9th percentile, which works out at about 146 on this scale, so a strict reading puts a 145 a point short, although societies publish their own cut-off tables for each accepted test and those can differ from the arithmetic. The Prometheus Society asks for the 99.997th percentile, about 160. See high-IQ societies and Mensa IQ score requirements.

What does an IQ of 145 predict?

Higher scores keep predicting better outcomes through the top of the range, but the link is a tendency in groups, not a promise for a person. At the far end, a long-running US study followed 320 youths identified before age 13 as top 1 in 10,000 in mathematical or verbal reasoning for nearly three decades, and found many of them in leadership positions in business, health care, law, the professoriate and STEM (Kell, Lubinski and Benbow, 2013). That is a rarer group than 145. For school and income outcomes, see does IQ predict school success and does IQ predict income.

Why do online tests say 145?

A short quiz that reports 145 is not comparable with a Wechsler or Stanford-Binet result. Online tests are untimed or loosely timed, unsupervised and often normed on whoever clicked, and some print scores above the 160 that supervised tests stop at. The same logic applies to quizzes that hand a pet an IQ: with no norm sample there is no test result behind the number (see cat IQ). Look for the test name, the scale and the date before trusting a number; what to check before trusting an online score sets out the checks, and what makes an IQ test official explains the difference.

If you scored 145

Treat it as roughly 140 to 150 on the scale and test it was measured on. Check that it was a full-scale score from a named test, note the standard deviation, and expect a retest to land a little lower. If you want your own number on a stated scale with its percentile and margin of error, take our IQ test.

Quick answers about an IQ of 145

  • Is 145 a good IQ? It is a very high score, in the top 0.14% on the standard scale.
  • What percentile is a 145 IQ? The 99.87th on a standard deviation 15 scale.
  • How rare is a 145 IQ? About 1 in 741.
  • Is 145 IQ genius? There is no official cut-off. Terman’s 1916 table used scores over 140, and “highly gifted” is usually set at about 145.
  • Is 145 enough for Mensa? Yes. The Triple Nine Society line is about a point higher.
  • How accurate is it? Read a reported 145 as roughly 140 to 150.

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