The IQ test for adults over 40: scored against your own age group, and what group studies say about speed and words

0 The short answer

An adult over 40 can take the same IQ tests as any adult, and a properly normed test scores them against adults of a similar age, so the number is not a verdict on their age. The options are a psychologist giving a full battery, a supervised society exam, free screeners of uncertain quality, and normed online batteries such as ACIS, which offers a Quick form at 15 dollars (about 45 minutes), an Optimized form at 30 dollars (about 110 minutes) and a Full Scale form at 50 dollars (about 175 minutes), prices read October 29, 2026. Group studies point the same way: vocabulary and knowledge tend to hold or keep rising into the 60s while processing speed tends to slip from early adulthood, so a profile at 45 often looks uneven, and that is a group average, not a forecast for any one person. The decisive limit is that an IQ test is not a memory test, a dementia screening or a diagnosis: a reader with memory concerns should see a clinician.

1 What Does an IQ Test Score Mean for Someone Over 40?

A score on a normed IQ test is a position inside a reference group, and for an adult over 40 the fair reference group is people of a similar age. The Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014), published jointly by the American Educational Research Association, the American Psychological Association and the National Council on Measurement in Education, say in Standard 5.8 that norms should refer to clearly described populations, and that these populations should include the individuals or groups with whom test users will ordinarily wish to compare their examinees. The comment to that standard names age groups among the differentiated norms that may be useful. Read plainly, a 45 year old who wants to know how they compare with adults will usually want to be compared with adults near 45, not with a pooled crowd of 20 year olds.

That is how adult batteries are built. Hartshorne and Germine (2015) note in their paper in Psychological Science that early IQ tests lumped everyone aged 16 and over into one homogeneous category called "adult," and that the WAIS-III manual now provides a distribution of scaled scores for each age group. Their re-analysis used the WAIS-III normative sample of 2,450 Americans aged 16 to 89, with 200 participants in each of the bins 35 to 44, 45 to 54 and 55 to 64. Each bin is one age group, and a scaled score in it says how a person performed relative to people in that bin.

Two consequences follow. First, the average of the reference group sits at the middle of the scale: on the standard scale used by the main adult batteries, which ACIS also reports, the mean is 100 and the standard deviation is 15, and the page on how IQ scores are normed explains the mechanics. A 45 year old and a 25 year old who each score 100 are each average for their own age group. They are not necessarily equal in raw performance on every task, and the later sections show why that matters. Second, the question "what is the average IQ for a 40 year old" has a built-in answer of 100 when the test is age normed. The more useful question is how the raw performance of 40 year olds differs from that of 25 year olds on each ability, and the page on average IQ by age treats that across the whole lifespan.

The same logic answers a common worry. Someone who takes an IQ test at 50 and fears that their age will drag the number down is picturing a test normed on one pooled adult group. With age bands, the comparison is built to take age into account. What it cannot do is remove everything else that differs between people of the same age, such as education, language or health, and the Standards make that point themselves in Standard 10.12, which says the interpretation of test scores should consider other factors that may influence a particular testing outcome, and lists educational level, effort, health status and the testing situation among them. A later section returns to that.

2 Which IQ Tests Can an Adult Over 40 Take, and What Do They Cost?

There are four routes, and they differ more in supervision, cost and what the report contains than in the age of the person taking them. Pearson publishes the WAIS-5, the Wechsler battery for adults, and its product page, read on October 29, 2026, gives an age range of 16:0 to 90:11, a qualification level of C, and completion times of 45 minutes for the 7 subtest Full Scale IQ and 60 minutes for the 10 primary index subtests. The complete print kit is listed at 1,784 dollars, a price that tells a reader the test is bought by professionals, not by the person tested. The page also says the test was normed on individuals whose primary language is English. A person over 40 therefore falls well inside the adult range, and nothing on the page treats midlife as a special case.

American Mensa's testing page, read on October 29, 2026, lists regular prices of 60 dollars for a proctored local group session and 99 dollars for private electronic testing, and says a qualifying score is at or above the 98th percentile of the general population. The page showed a promotion that ends October 31, which this page does not use. Mensa offers testing from age 14, so a person over 40 is eligible, but the exam answers one question only, whether the person qualifies.

The first row is the only one that includes a clinician who can ask why a profile looks the way it does. The table also shows why an adult should ask three questions of any test before paying: who the norm group is, whether anyone supervised the session, and what the report returns. The page on the best online IQ tests compares online options on exactly those points, and the page on where to take an IQ test lists in person and online routes together. The page on the IQ test for adults covers the general case before age enters the picture.

Two cautions come with that table. A free screener is not wrong because it is free, but a number with no named norm group cannot be placed on any age band, so a 50 year old who sees "112" cannot tell whether that means 112 among all adults, among test takers on that site, or something else. And a job screening practice test is built to predict how someone will do on a hiring assessment, which is a different purpose from estimating general cognitive ability. Neither is a stand-in for a normed battery.

3 What Do Group Studies Show About Cognition in the 40s and 50s?

Group studies agree that abilities do not move together in midlife: knowledge tends to hold or rise while speed and fluid reasoning tend to drift down, and the size of the drift depends on how the study was built. The summary below names the design of each study, because a result from comparing different people at one time and a result from following the same people over years answer different questions.

Hartshorne and Germine (2015) combined a re-analysis of the WAIS-III normative data with web samples, and the design was cross-sectional throughout, which means that different people of different ages were compared at one point in time. Their abstract reports that some abilities peak and begin to decline around high school graduation, some plateau in early adulthood and begin to decline in the 30s, and still others do not peak until the 40s or later. Their evidence combined 48,537 web participants with the normative data, and the point of the paper is that the age of peak performance depends on the ability measured.

Salthouse (2009) examined when decline begins, in a paper in Neurobiology of Aging. He reports that cross-sectional comparisons consistently show lower performance with higher age even within the range of 18 to 60 years, and that a major factor in the apparent disagreement with longitudinal studies is that people who take the same tests again benefit from prior test experience, which masks age-related declines in longitudinal comparisons. His conclusion is that some aspects of age-related cognitive decline begin in healthy, educated adults when they are in their 20s and 30s. That is a statement about averages and about particular aspects of cognition, not about a person's whole ability.

The Whitehall II study followed 5,198 men and 2,192 women, who were civil servants aged 45 to 70 when cognitive testing began in 1997 to 1999. Singh-Manoux and colleagues tested them three times over 10 years. All scores except vocabulary declined in all five age categories, from 45 to 49 up to 65 to 70, with faster decline in the older groups. For reasoning, the 10 year decline, expressed as change divided by the test range and multiplied by 100, was 3.6 percent among men aged 45 to 49 at baseline and 9.6 percent among men aged 65 to 70, and 3.6 percent and 7.4 percent among women. The authors conclude that cognitive decline is already evident in middle age, and this is the figure behind headlines that say decline starts at 45. Two details put it in proportion. The decline in the youngest group is small relative to the range of the test, and the same paper reports that comparing different age groups at one time overstated the decline for women because of cohort differences in education. In women aged 45 to 49 the longitudinal analysis showed a reasoning decline of 3.6 percent, and the cross-sectional comparison suggested 11.4 percent.

A second longitudinal study points the same way with a different, telephone-based battery. Hughes and colleagues analyzed the Midlife in the United States study, in which 2,518 people with the cognitive assessment at the third wave were aged 42 to 92 and had been tested on two occasions an average of 9 years apart. All subtests and factors showed very small but significant declines over the 9 years, with processing speed showing the earliest and steepest decrements, and people with higher educational attainment scored better on all tests except reaction time.

The Seattle Longitudinal Study, which Schaie summarized in 2005, followed people across the adult years and compared two kinds of evidence. In its cross-sectional data, four of the six ability factors showed consistent negative age differences, including inductive reasoning, spatial orientation and perceptual speed, which were significant at age 46, and the gap between the youngest and oldest groups on those four factors was about 2 standard deviations. In its 7 year longitudinal data, the earliest reliably observed decline was by age 60 for perceptual speed and numeric facility, by age 67 for inductive reasoning and spatial orientation, and by age 81 for verbal ability. Schaie reads the cross-sectional figures as misleading if taken as estimates of decline, and he puts the gap down mainly to cohort or generational differences. A later section returns to why the two designs differ.

The pattern that matters for an IQ test is therefore not "everything falls" and not "nothing changes." It is that different abilities follow different curves, so a person of 50 can have a vocabulary score above their reasoning score and be entirely typical. The page on how IQ changes with age gives the whole-lifespan view, and the page on fluid and crystallized intelligence gives the distinction these studies rest on.

4 What Happens to Vocabulary and Knowledge After 40?

Vocabulary and general knowledge are the abilities that group studies most consistently show holding or rising through the 40s and 50s. In the WAIS-III norm data Hartshorne and Germine found that the five tasks invoking learned knowledge, which they list as vocabulary, information, comprehension, arithmetic and similarities, peaked significantly later than nearly every other task, with vocabulary peaking around age 50. In the web sample the vocabulary peak came later, around age 65, and the authors suggest the difference may reflect cohort differences, because the Wechsler data were collected two decades earlier and the proportion of adults in cognitively demanding careers may have grown. They also say it could point to confounds in one or both datasets. Neither number is a rule about when anyone peaks.

Salthouse (2019) compared more than 5,000 adults cross-sectionally and almost 1,600 longitudinally in a paper in Psychology and Aging, and found that vocabulary knowledge increased until the decade of the 60s in cross-sectional, quasi-longitudinal and longitudinal comparisons alike. Singh-Manoux and colleagues found vocabulary the single score that did not decline in any age category over 10 years. Three designs, one direction.

In the CHC framework, which the page on the CHC model lays out, this is crystallized intelligence (Gc): the breadth and depth of acquired knowledge and the ability to use it. ACIS measures Gc with five subtests that make up its verbal comprehension index: Antonyms, Vocabulary, Information, Synonyms and Similarities. The Vocabulary subtest page describes the task as word definition questions, and the Information subtest page describes general knowledge about the world. A reader who wants the research on word knowledge and general ability can read the page on vocabulary and IQ, and the sibling page on the crystallized intelligence test treats Gc in depth.

Two limits keep this from becoming flattery. First, vocabulary and knowledge tasks reflect what a person has had the chance to learn, so they depend on education, reading and language. The ACIS technical manual says that verbal and knowledge tasks are affected by English proficiency and educational exposure, and ACIS is English only. A reader who learned English as an adult should read their Gc results with that in mind. Second, a high Gc is not evidence that the other abilities are intact, and a lower speed score is not evidence that Gc is weaker. The abilities are correlated but separable, which is why batteries report indices and not only one number.

5 What Happens to Processing Speed and Fluid Reasoning?

Processing speed is the ability group studies show falling earliest and most steadily, and fluid reasoning follows a slower, accelerating curve, so a timed task is where a 50 year old is most likely to feel the difference from their younger self. In the WAIS-III norm data, digit symbol coding, a task in which symbols must be matched to numbers against the clock, peaked in the late teens, earlier than any other task Hartshorne and Germine highlight. In their large web samples, processing speed again peaked first, working memory tasks around 30, and vocabulary later. Salthouse (2019) reports that the cross-sectional and quasi-longitudinal comparisons imply nearly linear declines from early adulthood in speed, and accelerating declines in reasoning. In the MIDUS data, speed had the earliest and steepest decrements. In Seattle, perceptual speed was the earliest to show reliable longitudinal decline, by age 60.

Processing speed (Gs) in CHC terms is the ability to perform simple tasks quickly and accurately under time pressure, and the ACIS processing speed index uses two subtests. The Coding subtest page describes matching symbols to numbers as quickly as possible, and the Symbol Search subtest page describes scanning symbols quickly and accurately. The page on processing speed explains why this domain is the one that declines first in group data, and the page on the processing speed test describes a short route to a speed index for readers who want only that.

Fluid reasoning (Gf) is solving novel problems with no stored answer. ACIS measures it with Matrix Reasoning, Figure Weights, Visual Number Series, Logic Grid and Complex Relations, and the Matrix Reasoning subtest page describes visual pattern problems that sample abstraction, logic and nonverbal reasoning. The studies above treat reasoning in different ways, so the safe summary is the one the Whitehall II numbers support: a measurable but small average decline from the late 40s, larger in the 60s. Hartshorne and Germine also found heterogeneity among fluid tasks in the WAIS-III data, with some peaking later than others, so "fluid reasoning" is not one curve.

What this means for the test, and not for the person, is practical. A timed subtest scored against age norms already accounts for the average slowing. A 50 year old who finishes fewer symbol items than a 25 year old can still land at the middle of their own age band. The mistake to avoid is reading a raw count of items finished as an age-free measure of intelligence, and the opposite mistake of assuming that a speed score below a vocabulary score means something is wrong. Gaps between indices are common, as the page on index score differences shows.

6 What Happens to Working Memory, and Is It the Same as Memory?

Working memory is the ability to hold and rearrange information for a few seconds while using it, it is a different construct from everyday memory, and measuring it does not tell you about either everyday forgetting or memory disorders. In the CHC model it is Gwm, and ACIS measures it with Digit Span, Alphanumeric Sequencing and Visual Sequence. The Digit Span subtest page describes forward and backward recall of digits, and ACIS presents Digit Span, like Alphanumeric Sequencing and Arithmetic, as audio, so those subtests need working sound.

The group evidence on this ability is mixed by task. In the WAIS-III norm data Hartshorne and Germine found digit span peaking in the early twenties. In their web data, visual and verbal working memory both peaked around age 30. These are cross-sectional results from different people at different ages, and the authors warn that cross-sectional data may be subject to cohort effects.

The page on a short term memory test treats memory tasks as a topic of their own. This page uses working memory only as one of the six areas an IQ battery covers, alongside verbal comprehension, fluid reasoning, quantitative reasoning, visual spatial ability and processing speed. A low or high Digit Span result on an IQ test is a score on a task, set against adults of a similar age, and it is not a finding about the health of anyone's memory. The next sections make that boundary explicit.

7 Why Do Studies Disagree About When Decline Begins?

The studies disagree because comparing different people at one time and following the same people over years each distort the picture in a known direction, so neither one is a forecast for an individual. A cross-sectional study sets 25 year olds beside 55 year olds. If the 55 year olds grew up with fewer years of schooling or less familiarity with tests, they look as though they declined when they may not have. Schaie (2005) states the mechanism directly: with a positive cohort difference, older people in a cross-sectional study look as if they had declined from an earlier peak even though they may have remained stable, and with a negative cohort difference the reverse happens. In the Seattle data he reports substantial positive and linear cohort differences for inductive reasoning and perceptual speed, of about one standard deviation over the 70 year range of birth cohorts studied.

A longitudinal study has the opposite problem. The same people take the same kinds of tests again, and practice helps. Salthouse (2009) argues that this is a major reason longitudinal studies show later decline than cross-sectional ones, because gains from prior test experience hide real change. Salthouse (2019) tested the idea by adding quasi-longitudinal comparisons, which draw on people from the same birth cohorts but with no prior test experience. Those comparisons looked more like the cross-sectional ones than the longitudinal ones, which he takes to mean that, at least up to about age 65, longitudinal age trends are distorted by prior test experience.

So researchers do not agree on a single age at which decline begins, and the honest summary is a range. Salthouse reads the evidence as showing slow decline in some abilities from early adulthood. Schaie reads the longitudinal data as showing reliable average decline in most abilities later, in the 60s and beyond, with verbal ability last. Singh-Manoux and colleagues found small declines in reasoning already in the late 40s, and also found that cross-sectional comparisons overstated the decline for women because of educational differences between cohorts.

For a reader considering a test, three points follow:

• Age-normed scores already absorb the average. The score compares you with people close to your age at the time the norms were collected, so the average slope of any of these curves is built into the comparison.
• A trend is not a trajectory. Every study above reports group means. None can say what will happen to any one 45 year old.
• A second attempt is not a clean remeasurement. If you take a test twice, prior test experience can raise the second result, which the sibling page on retaking an IQ test explains, and which is the same effect Salthouse describes in longitudinal data.

The Flynn effect is a further piece of the same puzzle, since Schaie notes that studies of successive cohorts of school children found substantial increments in intellectual performance over the past century. The page on the Flynn effect covers the norms side of it. The Standards make the consequence explicit in the comment to Standard 5.3: a score point defined as the mean of a reference population should no longer be read as average performance if the scale is held constant over time and the examinee population changes.

8 Where Does an IQ Test Stop, and Who Should You See About Memory Concerns?

An IQ test describes a profile of abilities at one moment relative to people of a similar age, and it is not designed, validated or sold to find memory problems or any cognitive disorder, so memory concerns belong with a clinician. This page is about ability tests, and it needs one clear line drawn through it. A person who is worried about their memory, who has noticed changes in thinking or in coping with everyday tasks, or who is worried about someone close to them, should talk to a doctor or a clinician, and should not wait for an online score or take comfort from one.

Three sources make the line firm. The Standards for Educational and Psychological Testing say in Standard 10.15 that interpretation of test or battery results for diagnostic purposes should be based on multiple sources of test and collateral information and on an understanding of the foundations and limitations of the tests, and the comment adds that a given pattern of test performances is a cross-sectional view of the individual in a particular context. Standard 10.1 says those who use psychological tests should confine their testing and related assessment activities to their areas of competence, demonstrated through education, training, experience and appropriate credentials. And the American Psychological Association publishes separate guidelines for the evaluation of dementia and age-related cognitive change. Mast and Levy (2022) give an overview of the 2021 revision of those guidelines in an abstract in Innovation in Aging. Evaluating dementia is a clinical activity with its own guidance, and it is a different activity from taking a consumer IQ test.

What follows for ACIS is plain. ACIS is online and unsupervised, and it is not a clinical or diagnostic instrument. A Digit Span or Alphanumeric Sequencing result in an ACIS report is a score on a working memory task set against adults of similar age. It is not a statement about memory in daily life and not a finding about health. An ordinary result is not reassurance and a low result is not a warning, because a session at home depends on sound, attention, sleep, mood and the device, which is the testing situation that Standard 10.12 asks interpreters to weigh.

Where a clinical question exists, the route is a clinician. The page on neuropsychological testing for adults describes what that assessment involves and what it costs. The page on IQ tests for adults over 60 covers the older age bands. The rest of this page is about ability, and only about ability.

9 How Should a Score at 45 or 55 Be Read?

Read a score as a position among adults of a similar age, with a range around it, and read the profile before the headline number. On the ACIS report, indices and the Full Scale IQ are on the standard scale with a mean of 100 and a standard deviation of 15, scaled subtest scores run from 1 to 19 with a mean of 10 and a standard deviation of 3, and the report gives percentiles and a 95 percent confidence interval. The page on the standard deviation of 15 explains why the numbers have those values, and the page on IQ score versus percentile explains why a score and a percentile are not interchangeable and cannot be averaged.

The confidence interval matters more than most readers expect. The Standards say in Standard 6.10 that interpretations should describe in simple language what the test covers, what scores represent and the precision of the scores, and the comment says precision might be shown by error bands or likely score ranges. A Full Scale IQ reported with a 95 percent confidence interval is telling the reader that the interval, not the single number, is the reasonable statement of where the person stands.

One subtest is less precise than the battery, and the Standards give the reason in Standard 2.3: the consistency of total scores may be acceptably high while subscores have unacceptably low reliability, depending on how they are defined and used. That is why a lone Coding score is a weaker basis for a conclusion about speed than an index built from two speed subtests, and why a Full Scale IQ is steadier than any single piece of it. The page on reliability and validity explains the vocabulary in general terms.

For a reader over 40, three reading habits help:

1. Compare indices with each other. A verbal comprehension index above a processing speed index is a shape that the group studies above make unsurprising in midlife.
2. Do not compare with the score you got at 22. Two scores from different ages are positions in two different reference groups, so the same raw performance can yield different numbers, and the second attempt also carries a practice effect.
3. Treat a score as a snapshot. It describes the tested abilities on the day, under the session conditions, with the stated error.

10 What Does an Unsupervised Session Need to Go Well After 40?

An unsupervised session works when the conditions are the ones the test assumes: a screen you can read comfortably, working sound, a quiet room and breaks taken between subtests rather than inside them. The Standards ask a test professional to take the capabilities of the test taker into account when deciding whether technology-based administration is appropriate, in Standard 10.9, and an unsupervised online test leaves that decision to the person at the keyboard.

A short checklist covers the points that most often matter:

• Sound. Digit Span, Alphanumeric Sequencing and Arithmetic present their items as audio and need working sound, so test your speakers or headphones before starting.
• Vision and screen. Use the glasses you normally use for a screen, and a display large enough to see symbols and patterns without strain. Timed visual subtests such as Coding and Symbol Search ask for visual scanning at speed.
• Input device. Use the mouse, trackpad or keyboard you are fastest and most accurate with, and keep it the same across the session.
• Time and breaks. ACIS allows breaks, saves progress between subtests and gives 30 days to complete a form. The Full Scale form takes about 175 minutes, so plan it across several sittings.
• Language. ACIS is English only. Layer Rotation, per the technical manual, carries no words at all, and the verbal subtests depend on English proficiency.

Do not start a session when you are unwell, exhausted or distracted, since the Standards list effort, health status and the testing situation among the factors that can influence an outcome.

11 Does a Score at This Age Predict Daily Life or Work?

A score tells you how you performed on specific tasks relative to peers, and group research shows that cognitive differences between ages in the laboratory often have small consequences in everyday life. Salthouse (2012) reviewed the question in the Annual Review of Psychology. He writes that adult age differences in a variety of cognitive abilities are well documented and that many of those abilities are related to success in the workplace and in everyday life, yet that increased age is seldom associated with lower levels of real-world functioning, and the reasons for this lab-life discrepancy are not well understood. The review closes by discussing possible explanations for why age-related declines often have little or no consequence in everyday functioning.

This matters for two readers. One is the 50 year old whose speed score sits below their vocabulary score and who reads that as a loss of competence. That inference goes further than the research supports, and the score does not measure experience, judgment or expertise. The other is the 45 year old whose Full Scale IQ is high and who expects it to guarantee anything about work. It does not. A test of general cognitive ability is one input to understanding a person, and it is not a measure of job performance.

It also bears on how the profile is read. Each domain is a defined set of tasks, and the ACIS report returns the domains separately so that a reader can see where they are strong, not to rank them. In Whitehall II, the 10 year reasoning decline for men and women aged 45 to 49 at baseline had the same point estimate, 3.6 percent, so a woman taking an IQ test at 40 or 50 is in the same position as a man: compared with adults of that age.

12 Where ACIS Sits, and What a Buyer Should Do

ACIS is one normed online option for an adult over 40 who wants a profile of abilities, and it is neither a clinical instrument nor a substitute for a psychologist, so the right use is an informed look at where you stand among adults near your age. The strengths are concrete. ACIS reports a Full Scale IQ with its 95 percent confidence interval in every form, indices on the standard scale where the form includes their subtests, and adult norms that cover ages 16 to 90, so a 45 year old is compared with adults of that age band. The Full Scale form measures all 20 subtests in six domains, and any session allows breaks, saves progress between subtests and gives 30 days to finish.

The limits are as plain. The test is online and unsupervised, it is not a clinical or diagnostic instrument, it is English only, and it is not for hiring, school accommodations or admission to high IQ societies. Nothing in an ACIS report can answer a question about memory problems, cognitive decline or dementia, and a person with that question should see a clinician. The technical manual notes that verbal and knowledge tasks are affected by English proficiency and educational exposure, and the technical manual is where the documentation of the instrument lives.

The Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014) set the bar by which a score of this kind should be judged. Standard 1.1 says the test developer should delimit clearly the population for which a test is intended and describe the construct it assesses, and Standard 5.8 says norms should refer to clearly described populations that include the groups with which users will wish to compare examinees. Standard 10.12 says interpretation should consider other factors that may influence a testing outcome, and Standard 10.15, described above, points away from using a single test for diagnostic conclusions. The American Psychological Association's guidelines for the evaluation of dementia and age-related cognitive change are the relevant APA guidance for a clinical question, and they concern the evaluation of dementia, which is a clinical task. Taken together, these say what a buyer should expect: a named population, a defined construct, a stated margin of error, and a refusal to stretch the score into medical territory.

Which form suits an adult over 40 depends on what the reader wants to see. The Quick form has six subtests in three domains: Similarities and Vocabulary for verbal comprehension, Matrix Reasoning and Figure Weights for fluid reasoning, and Digit Span and Alphanumeric Sequencing for working memory. It has no speed subtest, so it cannot show the contrast between words and speed that this page describes. The Optimized form has 13 subtests in five domains and adds Coding and Symbol Search, so it returns both a verbal comprehension view and a processing speed view. The Full Scale form covers all 20 subtests and reports six indices. Seven subtests are only in the Full Scale form: Information, Arithmetic, Mathematical Achievement, Visual Number Series, Complex Relations, Visual Puzzles and Visual Sequence. A reader who wants only one ability can use the Custom Test at 5 dollars per subtest, where any domain completed returns its full index score, with the Full Scale IQ requiring the Full Scale battery, and at 10 subtests the Full Scale form costs the same. The page on the free IQ test is the entry page for the no card trial.

Prices were read on October 29, 2026 and can change. ACIS is a one time payment with no subscription, and its guarantee reads, in its own words: "Full refund within 5 days if the report does not deliver the features described at checkout or a technical issue prevents you from accessing your results." That is a conditional refund, not an unconditional money back guarantee. There is one free trial per person, with no card, and finished trial subtests are kept if the person later unlocks a form that includes them.

13 Sources Behind This Page

Every figure above is traceable to one of the following, and each is linked at the point where it is used. Prices and age ranges were read on October 29, 2026 and can change. Any figure we derived ourselves is labeled in the text as our arithmetic.

• American Educational Research Association, American Psychological Association and National Council on Measurement in Education. Standards for Educational and Psychological Testing. American Educational Research Association, 2014. Standards 1.1, 2.3, 5.3, 5.8, 6.10, 10.1, 10.9, 10.12 and 10.15, read in the open access PDF on October 29, 2026.
• Hartshorne J, Germine L. When Does Cognitive Functioning Peak? The Asynchronous Rise and Fall of Different Cognitive Abilities Across the Life Span. Psychological Science, 2015, volume 26, issue 4, pages 433 to 443. Full text in PubMed Central: PMC4441622.
• Salthouse T. When does age-related cognitive decline begin? Neurobiology of Aging, 2009, volume 30, issue 4, pages 507 to 514.
• Salthouse T. Trajectories of normal cognitive aging. Psychology and Aging, 2019, volume 34, issue 1, pages 17 to 24.
• Salthouse T. Consequences of Age-Related Cognitive Declines. Annual Review of Psychology, 2012, volume 63, issue 1, pages 201 to 226.
• Singh-Manoux A, Kivimaki M, Glymour M, Elbaz A, Berr C, Ebmeier K, Ferrie J, Dugravot A. Timing of onset of cognitive decline: results from Whitehall II prospective cohort study. BMJ, 2012, volume 344, article d7622.
• Hughes M, Agrigoroaei S, Jeon M, Bruzzese M, Lachman M. Change in Cognitive Performance From Midlife Into Old Age: Findings from the Midlife in the United States (MIDUS) Study. Journal of the International Neuropsychological Society, 2018, volume 24, issue 8, pages 805 to 820.
• Schaie K. What Can We Learn From Longitudinal Studies of Adult Development? Research in Human Development, 2005, volume 2, issue 3, pages 133 to 158. Full text in PubMed Central: PMC1350981.
• Mast B, Levy S. APA Guidelines for the Evaluation of Dementia: Overview and Key Updates. Innovation in Aging, 2022, volume 6, issue Supplement 1, pages 198 to 199.
• Pearson Assessments. Wechsler Adult Intelligence Scale, Fifth Edition (WAIS-5) product page. Age range, qualification level, completion times, kit price and norming language, read October 29, 2026.
• American Mensa. Testing page. Regular prices for local group and private electronic testing, minimum age and qualifying percentile, read October 29, 2026.

14 Frequently Asked Questions