What does an IQ of 60 mean?
An IQ of 60 is higher than about 0.38% of people, so roughly 1 in 261 scores this low or lower. It is in the extremely low range on professional tests. People often ask what "mental age" goes with it; that idea comes from the earliest IQ tests for children and doesn't describe adults at all.
Where 60 sits on the bell curve
An IQ of 60 is 40 points below the average of 100, or 2.67 standard deviations. About 0.38% of people of the same age score lower, the shaded sliver at the far left of the curve below.
On a test with a standard deviation of 16, such as older Stanford-Binet editions, the same result would be about 57, and on the Cattell scale, which uses 24, about 36. Why scales differ.
A closer look at an IQ of 60
The first practical intelligence test, published by Alfred Binet and Théodore Simon in 1905, described children by the age whose typical performance they matched. IQ began as that mental age divided by real age, times 100. By that old formula, a 10-year-old performing like a typical 6-year-old would score 60.
Modern tests dropped the formula because it breaks down for adults, whose raw performance stops rising in the same way. Today an adult's 60 means a result about two and two-thirds standard deviations below other adults, not "the mind of a six-year-old". Adults with low scores have adult experience, interests and relationships, and describing them by a child's age is both inaccurate and unkind. On the Assessivo test, 60 means two correct answers out of 36.
How an IQ of 60 is classified
Different tests and manuals use different words for the same score, and the words have changed over time. Here is where 60 falls on each of the systems you are most likely to meet.
Sources: American Psychiatric Association, DSM-5 fact sheet on intellectual disability; World Health Organization, ICD-11, 6A00 disorders of intellectual development; Peltopuro, M. and others (2014), "Borderline intellectual functioning: a systematic literature review", Intellectual and Developmental Disabilities, 52(6), 419–443. WISC-V descriptors from Pearson's interpretive reports, as on our good IQ score guide.
Is an IQ of 60 an intellectual disability?
A score of 60 on its own never makes a diagnosis. The American Psychiatric Association's DSM-5 describes intellectual disability as "approximately two standard deviations or more below the population, which equals an IQ score of about 70 or below", and requires three things together:
- Low intellectual functioning, confirmed by a clinical assessment and individually given, standardised testing.
- Difficulties with everyday adaptive skills in at least one of three domains: conceptual (language, reading, maths, memory), social (communication, judgement, friendships) and practical (personal care, money, work and school tasks).
- A start during the developmental period, in childhood or adolescence.
Severity is set by those everyday skills, not by the IQ number. That is why only about 1% of people have an intellectual disability (a 2011 meta-analysis of 52 population studies found about 10 per 1,000), even though about 2.3% score below 70 on the bell curve. Because tests have a margin of error, DSM-5 treats roughly 65 to 75 as the uncertain zone around 70.
Sources: American Psychiatric Association, DSM-5 fact sheet on intellectual disability; Maulik, P. K. and others (2011), "Prevalence of intellectual disability: a meta-analysis of population-based studies", Research in Developmental Disabilities, 32(2), 419–436; Hall v. Florida, 572 U.S. 701 (2014), which cites the DSM-5 range of 65 to 75.
Could a score of 60 be wrong?
Low scores are the most fragile results on any test, because almost everything that goes wrong on the day pulls a score down. Common reasons include:
- Running out of time. On timed tests, including ours, an unanswered question counts as wrong.
- Nerves. A review of 238 studies found test anxiety consistently linked with lower scores.
- Tiredness. Sleep loss hits attention and speed hardest, which costs points against the clock.
- Language and format. Taking a test in a second language, on a small screen or in an unfamiliar format can lower a result without saying anything about reasoning.
What a 60 means on our test
On the Assessivo test, 60 means 2 correct answers out of 36. Every question has four options, so someone guessing every answer at random averages nine correct, a score of 78. Random guessing scores this low only about once in 379 attempts. The likeliest explanations are the clock, a refresh at the wrong moment or a very interesting phone, not your reasoning.
If any of this sounds like your session, retake the free IQ test when you are rested and have 25 quiet minutes. A score that moves a lot between attempts was never very solid.
Sources: von der Embse, N. and others (2018), "Test anxiety effects, predictors, and correlates: a 30-year meta-analytic review", Journal of Affective Disorders, 227, 483–493; Lim, J. and Dinges, D. F. (2010), "A meta-analysis of the impact of short-term sleep deprivation on cognitive variables", Psychological Bulletin, 136(3), 375–389. Guessing figures are worked out from the binomial distribution for 36 four-option questions.
What is the mental age for an IQ of 60?
The first IQ tests, for children, described performance as a "mental age": the age whose typical performance a child matched. IQ was mental age divided by real age, times 100. Run that old formula backwards and you get the figures below, for children only.
| Child's age | Performs like a typical child of about |
|---|---|
| 6 | 3 years 7 months |
| 8 | 4 years 10 months |
| 10 | 6 years |
| 12 | 7 years 2 months |
| 14 | 8 years 5 months |
For adults the idea doesn't work, which is why David Wechsler replaced it in 1939 with today's method: compare each person with others of the same age. An adult who scores 60 has an adult's knowledge, interests and experience. The score only says how their test performance compares with other adults'.
How common is an IQ of 60?
Line up 100 people of the same age and about 1 would score 60 or lower; the orange dot marks the place. In a town of 10,000 people, that is about 38.
The bar shows the likely range on a professional test, about five points either way: 55 to 65, from the 0.13th to the 0.98th percentile.
How 60 compares with nearby scores
| IQ | Percentile | Classic label | Score this low or lower |
|---|---|---|---|
| 50 | 0.04th | Extremely low | 1 in 2,330 |
| 55 | 0.13th | Extremely low | 1 in 741 |
| 60 | 0.38th | Extremely low | 1 in 261 |
| 65 | 0.98th | Extremely low | 1 in 102 |
| 70 | 2nd | Borderline | 1 in 44 |
Questions about an IQ of 60
What percentile is an IQ of 60?
An IQ of 60 is at about the 0.38th percentile: it is higher than about 0.38% of people of the same age, and roughly 1 person in 261 scores this low or lower.
Is 60 a low IQ?
Yes. 60 is 40 points, or 2.67 standard deviations, below the average of 100. On the classic Wechsler labels it is extremely low. A single score is an estimate with a margin of error of about five points, so 60 is best read as roughly 55 to 65.
Is an IQ of 60 a learning disability?
Not on its own. 60 is in the range where an intellectual disability (called a learning disability in the UK) is considered, but a diagnosis also needs significant difficulties with everyday skills that began during childhood, assessed by a qualified psychologist.
What is the mental age for an IQ of 60?
Mental age is an idea from the earliest tests for children. By the old formula, a 10-year-old scoring 60 would perform like a typical child of about 6 years. For adults it has no meaning: modern IQ tests compare adults with other adults, and an adult who scores 60 is not like a child.
What is the mental age of someone with an IQ of 60?
For a child, the old ratio formula gives mental age as IQ times real age divided by 100, so a 10-year-old scoring 60 would perform like a typical 6-year-old. For adults the idea doesn't apply: modern tests compare adults with other adults, and an adult with an IQ of 60 is not like a child.
Related: the IQ range chart, what counts as an average IQ, what IQ measures and misses and how to tell if an online IQ test is accurate.
A full IQ score of 60 combines several skills. Our guides explain each one: fluid vs crystallized intelligence, abstract reasoning, spatial reasoning, verbal reasoning and processing speed, or try the free pattern recognition test.
Information and support
If a professional assessment has given you, your child or someone you care for a score like 60, these organisations explain what it means in practice and what help is available.
Want a second reading?
Take the free Assessivo IQ test when you are rested and have 25 quiet minutes: 36 questions, and your estimated score and percentile as soon as you finish.
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