What makes an intelligence test real, and the routes an adult has

0 The short answer

An intelligence test is a standardized set of tasks, scored against a described reference group, that samples several mental abilities and combines them into a general score; a quiz that counts correct answers and attaches a number is not one. An adult has three real routes: a psychologist's battery such as the WAIS-5 (Pearson lists 45 minutes for the Full Scale IQ and about 60 for the 10 primary subtests, and one university training clinic lists 900 to 1,800 dollars for a comprehensive cognitive assessment), a normed online battery such as ACIS (Quick 25 dollars and about 45 minutes, Optimized 35 dollars and about 110 minutes, Full Scale 59 dollars and about 175 minutes, prices read on November 4, 2026, and able to change again), and free screeners, which are fine for curiosity but give a position among adults only when their page names an adult norm group. The decisive limit is that an unsupervised online score, ACIS included, is a personal estimate and not a clinical or institutional result.

1 What Makes Something an Intelligence Test and Not a Quiz?

Three properties turn a set of puzzles into an intelligence test: a standardized procedure, a described group of people your score is compared with, and enough different tasks to support one general score. Remove any one and what is left is closer to a quiz, however polished it looks. A quiz tells you how many items you got right. An intelligence test tells you where that result sits among adults like you, and how much to trust the position.

The Standards for Educational and Psychological Testing, the joint document of the American Educational Research Association, the American Psychological Association and the National Council on Measurement in Education, define a test in their 2014 edition as an evaluative device or procedure in which a systematic sample of a test taker's behavior in a specified domain is obtained and scored using a standardized process. Each word in that definition does work. "Systematic sample" means the tasks were chosen on purpose to cover a domain, not collected because they were fun. "Standardized process" means every person gets the same instructions, the same time rules and the same scoring, so that a difference between two scores is not a difference between two sets of conditions.

An intelligence test is a test whose specified domain is general cognitive ability. That is a wider target than a vocabulary quiz or a memory game, which sample one narrow ability. The distinction is drawn in an editorial signed by 52 researchers and reprinted in Intelligence in 1997 states that intelligence tests measure intelligence well, that they are among the most accurate of all psychological tests when accuracy means reliability and validity, and that they do not measure creativity, character, personality or other important differences among individuals. That is a statement of what the instrument is for, and also of what it is not for, and both halves matter to an adult deciding what to take.

Here is the practical test of any page that calls itself an intelligence test. First, does it name the group your score is compared with? Second, does it sample several kinds of reasoning, memory and knowledge, or only one? Third, does it report a general score with some statement of how precise that score is? A page that fails the first question is a quiz by the Standards' own logic, because a score with no described reference group has no position to report. The section on norms below takes up the first question, and the section on breadth takes up the second.

Two scope notes. This page is about the instrument and the routes. The ACIS test built for this reader has its own page, the page on the IQ test for adults. The definition of intelligence itself is the job of the page on what intelligence means, the taxonomy of formats belongs to the page on the types of IQ tests, and cognitive tests in general are covered by the page on what a cognitive test is. We also sell ACIS, so every ACIS statement here is limited to what the site and its prices say, and the last section states the conflict and the limits.

2 What Does an Intelligence Test Mean by "Intelligence"?

In a test, "intelligence" means a very general mental capability that shows up as reasoning, planning, solving problems, thinking abstractly, comprehending complex ideas and learning from experience, and it does not mean book learning, creativity or character. That is the definition given in the 1997 editorial in Intelligence mentioned above. The editorial adds that intelligence in this sense is not a narrow academic skill or a knack for taking tests.

The honest complication is that researchers do not share one definition. The American Psychological Association task force report by Neisser and colleagues (1996) observes that when two dozen prominent theorists were asked to define intelligence, they gave two dozen somewhat different definitions. The same report notes that individuals differ from one another in their ability to understand complex ideas, and that concepts of intelligence are attempts to clarify and organize that complex set of phenomena. It also reports that subtests measuring different abilities tend to be positively correlated, that a general factor called g represents what all the tests have in common, and that there is no full agreement on what g actually means.

Those three points settle how to read the word "intelligence" on a test page. First, it is a measured construct, defined by the tasks and the statistics, not a verdict on a person. Second, the construct is general because the tasks that measure different things move together across people. Third, the meaning of that shared variance is still debated, so a careful test describes what it measures instead of claiming to measure all of intelligence. The page on what IQ measures goes through the debate in detail and the page on the g factor test covers the general factor on its own.

Modern batteries describe the structure with the Cattell-Horn-Carroll model, usually abbreviated CHC. McGrew (2009) presents CHC as the combination of the Cattell-Horn Gf-Gc model and Carroll's three-stratum model, whose strong correspondence led to an umbrella term, and proposes it as a common taxonomy for research. In CHC, the broad abilities are named with short codes: Gf for fluid reasoning, Gc for crystallized knowledge, Gq for quantitative knowledge, Gv for visual processing, Gwm for working memory capacity and Gs for processing speed. A test that tells you which of these it samples, and how it combines them, is describing its construct. A test that says only "measures your intelligence" is not. The page on the CHC model lists the abilities and what each one covers.

One consequence is worth saying plainly. An intelligence test is built around a definition that reasonable researchers accept as a working one, and it is silent on a great deal that people value, such as creativity, judgment, wisdom, drive and character. That silence is by design. It is the reason a score should be read as one fact about a person and never as a summary of the person.

3 Is an Intelligence Test the Same Thing as an IQ Test?

In everyday search they are the same thing, but strictly an intelligence test is the instrument and an IQ is one score the instrument may report. The two phrases overlap so heavily that most adults who type "intelligence test" want what the rest of the web calls an IQ test. Where the difference matters is in what you can trust, and a few cases show it.

An instrument can be a real intelligence test and report no single IQ. A battery may report only domain scores for the abilities it covers, or may withhold a general score unless the full set of subtests is taken. A product can also report an "IQ" without being an intelligence test: a ten minute quiz that converts a count of correct answers to a number on the IQ scale produces the label without the norms or the breadth that give the label its meaning. So the reliable question is never "does it give an IQ" but "what is the number a position in".

The scale itself is a convention. Modern IQ scores place the average of the reference group at 100, and the editorial in Intelligence describes the spread as a bell curve with most people clustered around that average. ACIS reports its Full Scale IQ and six indices on a scale with a mean of 100 and a standard deviation of 15, with scaled subtest scores from 1 to 19 (mean 10, standard deviation 3), percentiles and a 95 percent confidence interval. The WAIS-5 also reports a Full Scale IQ, with five primary index scores, according to Pearson's own overview brochure.

A score and a percentile are different things, and mixing them up is the commonest reading error. A score of 130 is a position on the scale and a percentile says what share of the reference group scores at or below it. The page on IQ score versus percentile shows why the two cannot be averaged or swapped freely. Where the number came from historically belongs to the page on the history of IQ testing.

For the rest of this page we use "intelligence test" for the instrument and "IQ" for the score. When a section says an adult can take one online, it means a battery that returns a score on this scale and states whom the score is compared with.

4 Why Do Norms Decide Whether the Score Means Anything?

A score on an intelligence test means something only because it is compared with a clearly described group of people, and a test that does not describe its group cannot tell you where you stand. The Standards state the requirement in a single line: norms, if used, should refer to clearly described populations, and those populations should include the individuals or groups with whom test users will ordinarily wish to compare their own examinees. For an adult, that means a norm group of adults.

Two parts of the sentence carry the weight. "Clearly described" means you can find out who was in the group, from where and when. "Ordinarily wish to compare" means the group has to be the one you actually care about. A test normed on teenagers answers a question about teenagers, and a test normed on its own website visitors answers a question about people who visit that website. Neither is wrong as a description, and neither is the adult population. The APA's Guidelines for Psychological Assessment and Evaluation, approved in March 2020, say in Guideline 8 that psychologists strive to be aware of the need for test selection, scoring and administration to reflect the appropriate normative comparison, situational influences, effort and standardized administration.

Norms also age. When average performance on a test rises over time, an old norm group makes new test takers look better than they are. The meta-analysis by Pietschnig and Voracek (2015) pooled 271 samples from 31 countries, with nearly 4 million participants, covering 1909 to 2013, and estimated yearly gains of about 0.41 points for fluid IQ, 0.30 for spatial IQ, 0.28 for full scale IQ and 0.21 for crystallized IQ, with gains that have slowed in recent decades. At 0.28 points a year, that works out to roughly 2.8 points a decade (our arithmetic), which is why a publisher refreshes its norms and why the date of the norm sample belongs on the test page. Pearson says the US norms of the WAIS-5 were collected in 2023 and 2024 and that the sample matches the most current census on five key demographic variables.

The cleanest example of a test with no norms is a research instrument. The International Cognitive Ability Resource, ICAR, is hosted by a university statistics group, and its own FAQ answers the question "Do you have norms?" with "No". It adds that there was no attempt to use existing data or to collect data for that purpose, and that because of this you cannot infer an individual's IQ from it. It also says the instrument is intended for academic use, that individual results have to be interpreted with great care, and that it cannot replace a proper cognitive ability assessment under controlled conditions. That is a respectable position for a research tool and a useful reminder: a tool can be well made and still not be an IQ test for an individual.

For an adult choosing a test, norms come down to two questions you can ask of any page. Who is in the comparison group, by age and country? When was it collected? ACIS reports adult norms covering ages 16 to 90, and the documentation is in the technical manual. The mechanics of how a raw result becomes a standard score are covered in the page on how IQ scores are normed.

5 Why Does a Real Intelligence Test Use Many Different Tasks?

A real intelligence test samples several abilities because the general score is built from what the tasks share, and a single task cannot show what it shares with the others. If one test used only vocabulary, you would learn about word knowledge and nothing about reasoning with new material. If it used only matrices, you would learn about one kind of abstract reasoning and nothing about memory or speed.

The empirical reason goes back to the pattern Neisser and colleagues describe: tasks that look unlike each other are still positively correlated across people. The general factor in a battery is the statistical summary of that overlap. Warne and Burningham (2019) tested whether the pattern appears outside Western samples. They analyzed 97 samples from 31 countries, totaling 52,340 people, and a single factor emerged clearly in 71 of the samples, which is 73.2 percent. The first factor explained an average of 45.9 percent of the variance, a figure reported as similar to that in Western samples. The point for a test taker is not the percentage but the logic: if a general factor were an artifact of one culture, it would not keep appearing.

At the same time, the general factor is not the whole story, which is why batteries report more than one number. In CHC terms, the six domains ACIS reports, and the five that the WAIS-5 reports, are different broad abilities. Pearson's brochure lists the WAIS-5's five domains as verbal comprehension, visual spatial, fluid reasoning, working memory and processing speed. ACIS reports quantitative reasoning as a sixth index. A profile can be even or uneven, and an uneven profile is information a single number would hide.

Breadth has a precision benefit as well. The Standards state in their reliability chapter that if an assessment is shortened by decreasing the number of items or tasks, the reliability is likely to decrease, and that lengthening it with comparable tasks is likely to increase it. A longer battery is therefore not just more of the same: it is a larger sample of behavior, and each added task lowers the chance that one lucky or unlucky answer decides the result. That is also why a ten question quiz and a 20 subtest battery should not be compared as if they were the same kind of object.

Breadth is not the same as length for its own sake. A long vocabulary test measures vocabulary well and still says nothing about reasoning. The useful kind of breadth covers distinct abilities that a model names. Verbal and knowledge tasks also depend on schooling and language, a dependence the ACIS technical manual acknowledges. The page on the cognitive ability test shows how ACIS organizes its tasks into domains.

6 Which Routes Does an Adult Have, and How Do They Compare?

An adult has three routes to an intelligence test score: a battery given by a psychologist, a normed battery taken online, and free screeners, and they differ most in who supervises, whom the score is compared with and what you can do with the result. The table sets them side by side. Publisher and clinic facts were read on pages we opened on November 4, 2026, and ACIS prices were read on November 4, 2026. Every price can change.

The table hides one more difference that matters for planning. ACIS also offers a Custom Test at 10 dollars per subtest: any domain you complete returns its full index score and every subtest returns its scaled score, but the Full Scale IQ needs the Full Scale battery, and from six subtests the Full Scale form costs less than Custom. Breaks are allowed, progress is saved between subtests and you have 30 days to finish.

Read the table by the use you have in mind, not by price. If the score has to be accepted by a school, a clinic, an employer or a court, only the first row can help, and even then the party that asks for the number decides what it accepts. If you want a private, adult-normed picture of how your abilities compare, the ACIS rows give one, with the limits of any unsupervised online test. If you are curious and want to see what the tasks feel like, a free route costs nothing and tells you correspondingly little about your position. The page on where to take an IQ test lists the options in more places, and the full price breakdown of IQ tests covers the fees in every setting.

7 What Does a Psychologist's Battery Give You?

A psychologist's battery gives you a standardized administration watched by a trained examiner, a recent norm sample and an interpretation written for your situation, at a price in the hundreds to low thousands of dollars. The best known example for adults is the Wechsler Adult Intelligence Scale, fifth edition, WAIS-5, published in 2024. Pearson's overview brochure, read on November 4, 2026, calls the WAIS the most widely used measure of intelligence in adults and older adolescents ages 16 through 90:11, a claim that is the publisher's own. It describes a primary battery of 10 subtests covering five cognitive domains, a Full Scale IQ obtained from seven subtests, and a completion time of 45 minutes for the seven subtest Full Scale IQ and 60 minutes for the 10 primary subtests. It lists a qualification level of C, scoring on paper or on Pearson's online platform, and digital manuals and stimulus books.

Those are the publisher's completion times for the tests themselves, while a clinic fee covers a whole assessment, so the two numbers are not directly comparable. The only fee we found for an adult cognitive assessment on a page we opened is at a training clinic. The Emory University psychological center lists a fee for a comprehensive cognitive assessment of 900 to 1,800 dollars, set on a sliding scale based on income and household size, with the exact fee given at phone intake. The same page says the clinic is staffed by doctoral students in clinical psychology who practice under the direction of licensed clinical psychologists and receive intensive supervision. A fee for a comprehensive assessment may cover more than one test, so it is not a price for the WAIS-5 alone. Another university clinic, CU PATH at the University of Colorado, lists 2,100 dollars for a comprehensive adult evaluation, with a 200 dollar deposit to join the waiting list. That page describes neuropsychological evaluations for ADHD, learning disabilities and similar concerns and does not mention IQ testing, so we use it only to show the range in which comprehensive evaluations fall.

What does the examiner add that a screen cannot? The Standards note, in their chapter on psychological testing and assessment, that test administration may give skilled examiners the opportunity to observe the performance of test takers under standardized conditions. A person who sees you work can note fatigue, a misheard instruction or a response that suggests a problem the score alone would not. The APA guidelines make a related point: they state that standardized administration is most important because the validity of the responses may be compromised when adherence to standardization is not met. That is the strongest argument for the supervised route, and it is also the reason an unsupervised result is treated with more caution, as the section on online conditions below explains.

A caution about use: even a psychologist's battery can be wrongly chosen. Pearson says the US version of the WAIS-5 is available for use when the examiner determines that US norms are clinically appropriate, and the APA guidelines ask psychologists to consider whether the norm group fits the person assessed. That is a decision for a professional with your whole situation in view. For the official routes, the page on the professional IQ test sets out what a professional assessment involves and the page on the WAIS test online explains what can and cannot be done with that name on the internet. If you are in your fifties or later and wondering whether age changes the choice, the page on the IQ test for 50 year olds covers it.

8 What Can a Free Intelligence Test Give You, and What Can It Not?

A free intelligence test can show you what the tasks feel like and which abilities a battery samples, but unless it names an adult norm group and reports a precision for its score, it cannot tell you where you stand. Free is a price and not a quality, and free tools range from research instruments to quizzes that state no method. The way to sort them is the same three questions as before: whom is the score compared with, how many abilities are sampled and how precise is the score.

The research instrument described above shows the best case and its limits at once. ICAR is a large collection of assessment instruments for cognitive abilities that research groups use worldwide, and its FAQ is direct: the instruments have no norms, an individual's IQ cannot be inferred from them, test results of individuals have to be interpreted with great care and the instrument cannot replace a proper cognitive ability assessment under controlled conditions. A reader who finds an ICAR style test online and gets a score out of a possible total has learned something about that test and has not learned an IQ.

Quizzes and games usually fail a different way. A quiz that returns "your IQ is 128" from a short set of items has to answer where 128 comes from. If the page cannot say which adults the 128 is compared with, the number sits on the IQ scale without a reference group, and the Standards' logic applies: a score with no clearly described population has no position to report. If the page does say, in plain words, that the comparison group is its own recent visitors, then it is at least honest, and the number is a rank among those visitors. The page on the free IQ test and the page on the best online IQ tests compare specific options.

ACIS offers a free trial with no card, one per person: the site refuses a second trial from the same email address or the same browser. Finished trial subtests are kept if you later unlock a form that includes them, so the time is not wasted. The trial is a way to see the format, the instructions and a report before you pay, and the pages for Vocabulary, Matrix Reasoning and Digit Span describe three of the tasks in prose before you start. They do not substitute for the trial. A trial is also not a full battery, so we do not describe it as one.

The decision rule is short. If your question is "what do these tasks feel like", a free route answers it. If your question is "where do I stand among adults", you need a described norm group, which means the first or the last three rows of the table, not the free rows.

9 What Changes When You Take an Intelligence Test Online and Unsupervised?

Taking the test online and unsupervised removes the examiner, and with the examiner goes the guarantee that everyone worked under the same conditions, so the score has to be read as an estimate and your own conditions matter more. The Standards address this directly. In their discussion of fairness in testing they warn that unproctored test administrations, where standardization cannot be ensured, could give some test takers an advantage over others and that in these situations results should be interpreted with caution. They also say that examinees working on older, slower equipment may be unfairly disadvantaged relative to those on newer equipment, since differences in the speed of devices or the fidelity of visuals can let irrelevant factors influence test performance. And in the chapter on psychological testing, they say the interpreter of results should be informed if a test was unproctored.

None of this makes an online battery worthless. It makes the conditions part of the measurement, and several of them are in your hands. Use a device and a screen you are comfortable with. Take the test in a quiet room where you will not be interrupted. Do not look anything up and do not repeat a subtest, since a second pass measures practice and not ability. Take breaks between subtests, not during one, and use the progress saving ACIS provides: you have 30 days to finish, and splitting a long battery across days is allowed. Three ACIS subtests, Digit Span, Alphanumeric Sequencing and Arithmetic, present their items as audio and need working sound, so check your speakers or headphones before starting. The speed subtests, Coding and Symbol Search, depend on a responsive device, and the page on Coding describes the task.

The language also matters. ACIS is English only, and its technical manual notes that verbal and knowledge tasks can be affected by English proficiency and educational exposure. A reader who learned English as an adult may therefore score lower on verbal indices than on reasoning indices for reasons that have little to do with reasoning. That is a property of the test to keep in mind, not a judgment on the person.

Finally, the question to ask of any unsupervised result is what you plan to do with it. For a personal estimate, to see a profile, to decide whether a full evaluation is worth the money or to settle a curiosity, an unsupervised online score is a reasonable instrument if the norms are described. For anything an outside party decides on, it is not. The APA guidelines make the general point that psychologists consider the intended use of any scores when choosing a test, and the same logic applies to you as the person choosing.

10 How Should You Read the Score You Get?

Read an intelligence test score as a position with a margin of error, on a scale with a known mean and spread, and never as a fixed property of you. Four numbers do the work. Scaled subtest scores run from 1 to 19 with a mean of 10 and a standard deviation of 3. Indices and the Full Scale IQ sit on the scale with a mean of 100 and a standard deviation of 15. A percentile says what share of the reference group scored at or below you. A 95 percent confidence interval gives the range in which the score plausibly sits, and the Standards define a confidence interval as an interval that includes the parameter of interest with a specified probability.

If scores follow a normal curve with a mean of 100 and a standard deviation of 15, the conversion to percentiles is mechanical. Our arithmetic on the normal curve gives these approximate values.

Real norm tables are built from data and round differently, so treat the table as a guide to the shape and not as a lookup. For exact conversions, the IQ percentile calculator does the arithmetic.

Why does the interval matter? Because every score is an estimate. The Standards require that for each total score, subscore or combination of scores that is to be interpreted, estimates of the relevant indices of reliability and precision should be reported. That is Standard 2.3, and it is the reason a good battery reports precision for the Full Scale IQ and for each index and not only for the headline number. It also explains the ladder of confidence: a single subtest rests on a small sample of behavior, an index rests on several subtests, and a Full Scale IQ rests on all of them. By the Standards' own principle that more comparable tasks raise reliability, the higher rungs are usually more precise than the lower ones. The page on reliability and validity defines the terms, and ACIS publishes its documentation in the technical manual.

Three habits keep a reader out of trouble. First, read the interval before the point estimate, and compare two scores only when their intervals are clearly apart. Second, look at the shape of the profile before the total: an index well above or below the others means the average hides something. Third, never read a group statistic as a statement about you. The editorial in Intelligence states that a high IQ no more guarantees success than a low IQ guarantees failure, and that many other factors affect performance in education, training and work. The score tells you about one set of abilities on one day under one set of conditions.

A final point on what a score cannot do. It is not a diagnosis. An intelligence test sampling cognitive abilities is one input in a clinical evaluation done by a qualified professional, and an unsupervised online score is not clinical evidence at all. If you suspect a condition, the route is a clinician.

11 Which ACIS Form Fits, and What Does Each Part Measure?

ACIS offers three forms of one battery, Quick, Optimized and Full Scale, and the right one depends on whether you want an estimate, a profile across several abilities or all six indices. Every form reports a Full Scale IQ with its 95 percent confidence interval. The Full Scale form measures all 20 subtests, and the shorter forms sample fewer tasks, which by the principle above means a less precise score.

The 20 subtests sit in six CHC domains, each reported as an index. The Verbal Comprehension Index, VCI, covers crystallized knowledge, Gc, through Antonyms, Vocabulary, Information, Synonyms and Similarities. The Fluid Reasoning Index, FRI, covers fluid reasoning, Gf, through Matrix Reasoning, Figure Weights, Visual Number Series, Logic Grid and Complex Relations. The Quantitative Reasoning Index, QRI, covers Gq through Mathematical Achievement and Arithmetic. The Visual Spatial Index, VSI, covers Gv through Visual Puzzles, Layer Rotation and Spatial Comprehension. The Working Memory Index, WMI, covers Gwm through Digit Span, Alphanumeric Sequencing and Visual Sequence. The Processing Speed Index, PSI, covers Gs through Symbol Search and Coding. The technical manual is the place for the full documentation.

Each subtest has its own page, and the pages describe the tasks without reproducing items. Reading a few before paying is useful, and the Vocabulary and Matrix Reasoning pages above are two. Similarities asks you to compare concepts, which samples abstract verbal reasoning. Figure Weights uses balance-scale problems that sample fluid reasoning and quantitative logic. Alphanumeric Sequencing asks you to reorder letters and numbers and needs working sound. Visual Puzzles asks you to assemble shapes mentally and sits in the visual spatial domain, and Symbol Search asks you to scan symbols quickly and accurately.

• Quick, 25 dollars, about 45 minutes. Six subtests in 3 domains: Similarities, Vocabulary, Matrix Reasoning, Figure Weights, Digit Span and Alphanumeric Sequencing. A fast, adult-normed estimate, with the widest band of the three forms in principle.
• Optimized, 35 dollars, about 110 minutes. Thirteen subtests in 5 domains, adding Antonyms, Synonyms, Logic Grid, Spatial Comprehension, Layer Rotation, Coding and Symbol Search. A profile across five domains.
• Full Scale, 59 dollars, about 175 minutes. All 20 subtests in six domains. Seven subtests appear only here: Information, Arithmetic, Mathematical Achievement, Visual Number Series, Complex Relations, Visual Puzzles and Visual Sequence.

Prices were read on November 4, 2026, and can change again. The technical manual also lists composites built from predefined subtest sets, available when their subtests are available. Two of its descriptions are easy to quote: the Cognitive Proficiency Index combines working memory and processing speed as cognitive proficiency, and the Nonverbal Index emphasizes nonverbal reasoning, visual spatial ability, working memory and speed with minimal reliance on verbal content. The General Ability Index is among the composites the manual lists.

If you cannot decide, the page on which IQ test to take walks through the choice, and the how smart am I test page addresses the plain version of the question.

12 Where ACIS Sits, and What a Buyer Should Do

ACIS is an adult-normed online battery that gives a private, structured estimate of where your abilities sit, and it is not a clinical instrument, a supervised test or a credential. We sell it, so read this section as the disclosure of that conflict and of the limits.

The strengths are specific. ACIS compares you with adult norms covering ages 16 to 90, samples up to 20 subtests in six CHC domains, reports a Full Scale IQ and six indices with a 95 percent confidence interval and a scaled score for every subtest, costs one time with no subscription, and lets you stop and resume across 30 days. The site states a refund condition that you should read before paying: "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." It is not an unconditional guarantee.

The limits are as specific. ACIS is online and unsupervised, in English only, and on the research page the site states that it "is not intended for clinical diagnosis, hiring decisions, accommodation determinations or admission to high IQ societies" (read on the page on ACIS for research). Its manual notes that verbal and knowledge tasks are affected by English proficiency and educational exposure. A score from it is a personal estimate. It does not replace an assessment by a psychologist when a decision, a diagnosis or an accommodation depends on the number.

The Standards for Educational and Psychological Testing (AERA, APA and NCME, 2014) say how a buyer should treat any such score. Standard 5.8 asks for norms that refer to clearly described populations, Standard 2.3 asks that precision be reported for each score that is interpreted, Standard 3.4 and its comment ask that unproctored results be read with caution, and Standard 1.0 asks that each intended interpretation of a score for a specified use be clearly articulated and supported by validity evidence. The APA's Guidelines for Psychological Assessment and Evaluation (2020) add that test selection should reflect the appropriate normative comparison and standardized administration. Applied to you: check the comparison group, read the interval, record the conditions you took it in, and use the result only for the purpose it supports.

What should a buyer do next? If the question is personal, start with the free trial, which needs no card, read the technical manual for the documentation and pick the form that matches the profile you want. If the score must be accepted by someone else, book a psychologist and ask which instrument and which examiner that party accepts. If you are not sure, take the free trial first, look at the report and decide with the format in front of you.

13 Sources Behind This Page

Every figure and attribution on this page traces to one of the sources below, each opened on November 4, 2026 or checked by DOI against Crossref.

• American Educational Research Association, American Psychological Association and National Council on Measurement in Education (2014). Standards for Educational and Psychological Testing. American Educational Research Association. Open access edition.
• American Psychological Association, APA Task Force on Psychological Assessment and Evaluation Guidelines (2020). APA Guidelines for Psychological Assessment and Evaluation. Approved by the APA Council of Representatives, March 2020. PDF.
• Neisser, U., Boodoo, G., Bouchard, T., Boykin, A., Brody, N., Ceci, S., Halpern, D., Loehlin, J., and three coauthors (1996). Intelligence: Knowns and unknowns. American Psychologist, 51(2), 77 to 101. DOI.
• Gottfredson, L. (1997). Mainstream science on intelligence: An editorial with 52 signatories, history, and bibliography. Intelligence, 24(1), 13 to 23. DOI.
• McGrew, K. (2009). CHC theory and the human cognitive abilities project: Standing on the shoulders of the giants of psychometric intelligence research. Intelligence, 37(1), 1 to 10. DOI.
• Warne, R., and Burningham, C. (2019). Spearman's g found in 31 non-Western nations: Strong evidence that g is a universal phenomenon. Psychological Bulletin, 145(3), 237 to 272. DOI.
• Pietschnig, J., and Voracek, M. (2015). One century of global IQ gains. Perspectives on Psychological Science, 10(3), 282 to 306. DOI.
• Pearson Clinical Assessment (2025). WAIS-5 overview brochure, Canada. Pearson Education. Brochure PDF, read November 4, 2026.
• Emory University Psychological Center. Frequently asked questions: fees for a comprehensive cognitive assessment. Emory page, read November 4, 2026.
• University of Colorado Boulder, Clinical Psychology. CU PATH, psychological assessment clinic. CU PATH page, read November 4, 2026.
• International Cognitive Ability Resource (ICAR) project page and FAQ, TU Dortmund. ICAR page, read November 4, 2026.

14 Frequently Asked Questions