IQ tests for teens: which tests are used at ages 13 to 19

The right IQ test for a teenager depends almost entirely on age. Through age 16, the standard individually administered test is the Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V), which the publisher Pearson norms for ages 6:0 through 16:11. From age 16:0 onward, examiners can switch to adult instruments such as the Wechsler Adult Intelligence Scale, Fifth Edition (WAIS-5), which covers ages 16 through 90. Alongside these clinical tests, most teenagers encounter group ability tests at school, such as the CogAT or the OLSAT. This article walks through each option for ages 13 to 19, explains how stable scores are during adolescence, and covers when formal testing is actually worth pursuing. Parents of younger children should start instead with our guide to IQ testing for kids, which covers ages 12 and under in detail.

Modern IQ tests report a "deviation IQ," a score that compares a person's performance to other people of the same age. A 14-year-old is compared to other 14-year-olds, and an 18-year-old to other 18-year-olds, with the average for each age group set at 100 and a "standard deviation" (a measure of how spread out scores are) of 15 points.

This is why the test's "norm sample," the reference group used to convert raw performance into an IQ score, matters so much. Reasoning ability grows rapidly during adolescence, so a test scored against the wrong age group produces a misleading number. Giving a 14-year-old a test normed on adults will typically understate their standing relative to their actual peers, and an unnormed online quiz has no legitimate reference group at all. Test publishers handle this by building separate instruments, with separate norm samples, for childhood and adulthood, and the boundary between them falls right in the middle of the teenage years.

For most of the teen years, the gold-standard individual test is the WISC-V. According to Pearson, the WISC-V was published in 2014, covers children aged 6:0 through 16:11, and takes roughly 60 minutes for the core subtests. It measures overall intellectual ability along with five cognitive domains, producing a full-scale IQ plus index scores that show where a teen's particular strengths and weaknesses lie. We describe the test's structure and scoring in more depth in our article on the WISC test.

A licensed psychologist or other qualified examiner administers the WISC-V one on one, which is a real advantage for younger teens: the examiner can observe effort, attention, and anxiety, and can note when a score probably understates ability. That context is a large part of what families pay for in a professional evaluation, and it is something no group test or online test can replicate.

Pearson published the WAIS-5, the current adult Wechsler scale, in 2024. The publisher lists its age range as 16:0 through 90:11, with administration taking about 45 minutes for the seven-subtest full-scale IQ or about 60 minutes for the ten primary index subtests. Like the WISC-V, it is an individually administered clinical instrument given by a qualified examiner.

Notice the overlap: a 16-year-old falls inside the range of both tests. In that window the examiner chooses, and the decision usually turns on practical factors such as which norms are most recent and whether the teen may be retested in adulthood, since starting on the adult scale makes later comparisons cleaner. From age 17 the WISC-V is no longer an option, and any individually administered IQ testing for a 17-, 18-, or 19-year-old proceeds on adult instruments.

Many teenagers have already taken an ability test without a psychologist in the room. Schools administer group tests to whole classrooms, mainly for gifted-program screening and instructional planning.

• CogAT: the Cognitive Abilities Test, published by Riverside Insights, is used from kindergarten through grade 12 and measures verbal, quantitative, and nonverbal reasoning. It is one of the most common instruments American schools use to identify students for gifted and advanced programs.

• OLSAT 8: the Otis-Lennon School Ability Test, Eighth Edition, published by Pearson in 2003, covers kindergarten through grade 12 in its paper format and assesses verbal, nonverbal, and quantitative ability.

Group tests are efficient and reasonably accurate for screening, but they are not diagnostic evaluations. Scores are usually reported as percentile ranks or ability indexes rather than clinical IQ scores, and a single group testing session cannot rule out the attention, motivation, or testing-condition problems an individual examiner would catch. When a group test result triggers a high-stakes decision, schools and psychologists generally confirm it with an individually administered test.

Adolescence is the period when scores settle toward their adult levels, but individual teens can still shift. In a brain-imaging study published in Nature in 2011, Sue Ramsden and colleagues tested 33 healthy, neurologically normal young people early and late in adolescence and found that verbal and nonverbal IQ rose in some individuals and fell in others, with the changes tracking corresponding grey-matter changes in speech-related and movement-related brain regions. The authors concluded that a teenager's intellectual standing relative to peers can genuinely move during these years, in either direction.

At the same time, the rank-order stability of scores from late childhood onward is substantial. In a follow-up of the 1932 Scottish Mental Survey published in the journal Intelligence, Ian Deary and colleagues re-tested 101 adults at age 77 on the same test they had taken at age 11 and found the two scores correlated 0.63, rising to about 0.73 after correcting for the restricted ability range of the re-tested sample. In plain terms, a score from adolescence predicts adult standing fairly well for most people, while leaving room for meaningful individual change. Both findings fit the broader evidence we review in does IQ change with age.

The practical takeaway for parents: a score obtained at 13 or 14 is informative but should not be treated as a permanent label, and a consequential decision made years later deserves a current score, not one from middle school.

Formal IQ testing costs time and, privately, often significant money. It tends to be worth it in a few specific situations.

• Gifted program placement: many districts require a recent ability score for entry into advanced coursework or gifted services, sometimes from a group screener and sometimes from an individual test.

• Evaluation for learning difficulties: when a teen struggles despite effort, an IQ test given as part of a comprehensive psychoeducational evaluation helps distinguish a specific learning disorder from other explanations, since diagnosis depends on comparing achievement to measured ability.

• Documentation for accommodations: applications for extended time or other supports on schoolwork and standardized tests typically require recent formal testing.

• Self-knowledge for older teens: an 18- or 19-year-old weighing educational and career options can reasonably want an accurate picture of their cognitive strengths, in which case a well-normed adult test is appropriate.

If none of these apply, there is usually no urgency. A teenager's day-to-day schooling already generates plenty of evidence about how they are doing, and a test score adds the most value when a concrete decision hangs on it.

Once a teenager turns 18, the full range of adult tests opens up, including well-built online options. The RIOT IQ test, developed by RIOT IQ with psychometrician Dr. Russell T. Warne, is designed for adults 18 and older. It consists of 15 subtests across six cognitive indices (verbal reasoning, fluid reasoning, spatial ability, working memory, processing speed, and reaction time), takes about 52 minutes, and reports scores on the familiar mean-100, standard-deviation-15 scale. That makes it a legitimate option for an 18- or 19-year-old who wants a serious measure of general cognitive ability without a clinical appointment, though it does not replace an individually administered diagnostic evaluation when a disability determination or clinical question is on the table. Younger teens should stick to age-normed instruments like the WISC-V and school group tests. If you are 18 or older and curious where you stand, you can take the RIOT IQ test online.

An individually administered evaluation at 13 uses the WISC-V, which Pearson norms for ages 6:0 through 16:11. At school, a 13-year-old is more likely to encounter a group ability test such as the CogAT or OLSAT.

Yes. The WAIS-5 age range begins at 16:0, so 16-year-olds fall in the overlap between the WISC-V and the WAIS-5, and the examiner selects whichever instrument fits the situation better.

Only at 18 or 19. The RIOT IQ test is normed for adults 18 and older, so scores for younger teens would not be meaningful. Teens under 18 should use age-normed tests such as the WISC-V.

They can. A 2011 Nature study found measurable rises and falls in individual teenagers' verbal and nonverbal IQ across adolescence. Long-term follow-up studies still show substantial stability for most people from late childhood into adulthood.

Not exactly. Group tests like the CogAT and OLSAT measure closely related reasoning abilities and are useful screeners, but they are usually reported as percentiles or ability indexes and lack the diagnostic depth of an individual evaluation.

It is 100 at every age, by construction. IQ scores compare each person to peers of the same age, so the average 13-year-old and the average 19-year-old both score 100 relative to their own age group.

1. Pearson. (2014). Wechsler Intelligence Scale for Children, Fifth Edition (WISC-V). pearsonassessments.com

2. Pearson. (2024). Wechsler Adult Intelligence Scale, Fifth Edition (WAIS-5). pearsonassessments.com

3. Pearson. (2003). Otis-Lennon School Ability Test, Eighth Edition (OLSAT 8). pearsonassessments.com

4. Riverside Insights. (n.d.). CogAT: Cognitive Abilities Test. riversideinsights.com

5. Ramsden, S., Richardson, F. M., Josse, G., Thomas, M. S. C., Ellis, C., Shakeshaft, C., Seghier, M. L., & Price, C. J. (2011). Verbal and non-verbal intelligence changes in the teenage brain. Nature, 479, 113-116. nature.com

6. Deary, I. J., Whalley, L. J., Lemmon, H., Crawford, J. R., & Starr, J. M. (2000). The stability of individual differences in mental ability from childhood to old age: Follow-up of the 1932 Scottish Mental Survey. Intelligence, 28(1), 49-55. abdn.elsevierpure.com

Hero photo: a student seen from behind writing a university-entrance exam in Donostia. Photo by Joxemai, CC BY-SA 3.0, via Wikimedia Commons; cropped to 16:9.