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Professional TestsIs there math on an IQ test? How much of a score rests on it, and which tests leave it out
Arithmetic counted toward the WAIS-IV Full Scale IQ but sits outside the WAIS-5 seven. See which subtests use calculation and which ACIS forms skip it.
Professional TestsThe IQ test for teenagers: what a 16 or 17 year old can take, and who has to say yes
Pearson's WISC-V ends at 16:11 and its WAIS-5 starts at 16:0, so age 16 is the overlap. See which IQ test a teen can take, what it costs and who consents.
ArticlesVocabulary IQ test: how well word knowledge reflects general ability
Vocabulary loaded 0.70 on g in the WAIS-IV normative sample, second of ten core subtests. How a normed vocabulary IQ test differs from a word quiz.
Professional TestsThe IQ test for couples: how two partners take a real test and compare the scores fairly
Two partners can each take a normed IQ test from 15 dollars. Our arithmetic: about 1 in 3 couples differ by 15 points or more. See how to compare them fairly.
ArticlesA visual memory test for adults: the four item limit, the Corsi span, and how to take a normed one
Visual working memory holds about four items. See how Corsi span, long term recall and fluid reasoning differ, and where to take a normed visual memory test.
Professional TestsThe IQ test for career guidance: what an ability profile adds to interests and values
Cognitive ability tests predict job performance at .31 in the 2022 revision. See what an IQ profile adds to a career choice, what it leaves out and its cost.
ArticlesA spatial IQ test that reports a normed index, not a quiz
Spatial ability tracked 400,000 students for 11 years and marked who reached STEM degrees. Compare test options and take a normed spatial index from 15 dollars.
Professional TestsAn IQ test for autistic adults: what to take, what the research shows and how to read the profile
No IQ test diagnoses autism. A 2007 study of autistic children found Raven scores 30 percentile points above Wechsler; a replication found 9. See what to take.-
Take the assessment
You get a profile, not a number
ACIS measures six CHC domains across 20 subtests and reports each one with its own normed score.
ArticlesA pattern recognition test: what it measures, whether IQ is just that, and where to take a normed one
Raven's shares about 50 percent of its variance with g (Gignac, 2015). What a pattern recognition test measures, the meme, autism research and normed options.
Professional TestsIQ testing for adults with ADHD: which test to take, what it shows and why one score is not enough
A 2006 meta-analysis found only a small Full Scale IQ gap in adults with ADHD. See which test to take, what it cannot diagnose and how to read the profile.
ArticlesA number series test, explained: what it measures, where it appears and how to take a normed one
A number series test measures rule induction plus number knowledge. Woodcock-Johnson V moved it out of its core Gf cluster. See the research and your options.
Professional TestsWhich IQ profile test gives you a profile you can trust
Which IQ profile test shows strengths, not one number? In a WAIS-IV normal sample, 49 percent had a 15 point index gap. See the options and how to read one.
ArticlesMental rotation test online: the 1971 task, the 24 item MRT and a normed spatial score
The redrawn Vandenberg and Kuse MRT has 24 items and is copyrighted. See how it differs from the 1971 Shepard and Metzler task and free online copies.
Professional TestsWhat the Human Benchmark tests measure, and what they cannot tell you about IQ
What Human Benchmark's reaction, memory, chimp, aim and typing games measure in CHC terms, what research links them to IQ, and which normed subtests match.
ArticlesMath IQ test for adults: what a normed one scores, and why math is two abilities
A normed math IQ test scores learned math (Gq) apart from reasoning (Gf). ACIS tests both for 10 dollars in Custom. Formats, anxiety and how to read the score.
Professional TestsThe dyslexia friendly IQ test: which parts need reading and which do not
In a study of 100 students with dyslexia, fluid intelligence showed no significant gap. See which IQ subtests need reading, which are audio, and how to sit one.-
Free trial
Try ACIS before you decide
Free trial, no card required. Full report from $15.
ArticlesLogic IQ test: how deduction is scored and where to take one
A logic IQ test scores deduction, one of three narrow abilities in fluid reasoning. See the formats, the training evidence and where to take a normed one.
Professional TestsThe chess IQ test, explained: what your Elo rating really says about intelligence and which test measures it
A corrected meta-analysis puts chess skill and cognitive ability at 0.22. See what Elo is, what a real IQ test measures and which test fits a player.
ArticlesA general knowledge IQ test: what the score reflects and where to take a normed one
Is a general knowledge quiz an IQ test? Only with norms. What 141 undergraduates showed (Rolfhus and Ackerman, 1999) and where adults can take a normed one.
Professional TestsThe cheapest IQ test that is still a real score, ranked by price from free to a clinic
ACIS Quick is 15 dollars online; two clinics list 100 to 400 and 900 to 1,800; a 1 dollar trial can reach 390.87 in a year. Prices read October 28, 2026.
ArticlesVerbal vs quantitative ability: math person or words person?
Math minus verbal score, called tilt, separated STEM from humanities paths in 2,409 gifted youth over 25 years. See the evidence, the critique and your gap.
Famous IQTony Stark's IQ: the 270 credited to a society and what Marvel prints
Looper credited Tony Stark's 270 to an IQ society database, a fan wiki gives 186, and Marvel prints neither. See each source and why 270 is 11.3 deviations up.
IQ OutcomesDoes obesity lower IQ? What the cohorts and genetic studies show
A 2024 meta-analysis found school-age children with obesity scored 5.26 IQ points lower. Cohorts and genetics on which came first, and what stays unproven.
Professional TestsThe WASI-II explained: four subtests, two forms and who may give it
The WASI-II (Pearson, 2011) has 4 subtests and takes 30 minutes, or 15 with 2. See what it scores, what it omits, who may give it and what the kit costs.-
Full Scale
All 20 subtests in one report
The Full Scale assessment covers 6 domains with index scores and a Full Scale IQ.
ArticlesThe Stroop test and IQ, and what the interference score measures
Stroop found conflicting words slowed color naming by 47 seconds in 1935. Studies tie the interference score to IQ only modestly. See what it measures.
Famous IQSherlock Holmes's IQ: the 190 that Doyle never wrote
Sherlock Holmes's IQ of 190 traces to a 1999 estimate by professor John Radford, not to Doyle. Read the canon, the source trail and why 190 sits 6.0 SD up.
IQ OutcomesIs math ability the same as IQ? What the meta-analyses actually found
Fluid reasoning correlates .41 with math across 680 studies, and g accounted for 58.6 percent of English math exam variance. See what stays unshared, by study.
Professional TestsThe IQ test in Australia: Mensa, psychologists and online options, with costs and the norms question
Mensa Australia charges 75 dollars and reports a percentile; university clinics list 400 to 600 and a private WAIS 1,680. Fees read October 20, 2026.
ArticlesSpearman's law of diminishing returns, a pattern still in dispute
A meta-analysis of 106 articles and 408 studies found g loadings fall as ability rises, yet artifact critiques dispute why. Every study sourced and weighed.
Famous IQLight Yagami's IQ: the 211 that circulates and what the Death Note databook rates
The Death Note databook rates Light Yagami 9 out of 10, not an IQ. The 211 comes from a 2023 article with no test and would sit 7.40 standard deviations up.
IQ OutcomesHigh-IQ quirks: nine viral habits traced to the study behind each
Nine habits blamed on high IQ, from swearing to messy desks, each traced to its study. A 2019 replication of 100 people found no messy desk effect.
Professional TestsThe Eysenck IQ test, read from its own pages: what the 1962 book and online quiz each document
The Eysenck IQ test is a 1962 Penguin book plus a free 50 item, 30 minute online quiz. See what each documents, what is missing and what score either supports.
ArticlesEinstein's riddle, the 2 percent claim and what the puzzle really measures
Einstein's riddle was first printed in Life International on December 17, 1962, as far as anyone has shown. No source backs its 2 percent claim.
Famous IQForrest Gump's IQ: 75, 61 and 70 traced to their sources
Forrest Gump's IQ is 75 in the film's screenplay. The 1986 novel gives 61 in a Kirkus quote and 70 elsewhere. Trace each figure and the school cutoff of 80.
IQ OutcomesAre smart people more empathetic? What the meta-analyses actually measured
Meta-analyses link IQ to tests of reading minds and feelings at 0.19 to 0.24. Evidence on caring is thinner. Every study sorted by empathy type and measure.
Professional TestsBlossomUp IQ test reviewed: the report fee, the 7 day trial and what the score rests on
BlossomUp IQ test review: its terms give a 1.95 dollar report fee, a 7 day trial, then a plan such as 29.95 dollars a month. Read October 20, 2026.
ArticlesThe abstract reasoning test and IQ: one ability, not the whole score
Gignac found Raven's shares about 50 percent of its variance with g. See what an abstract reasoning test covers, what it leaves out and what a retest changes.
Famous IQCharles Manson's IQ: what the 109 and the 121 rest on
Charles Manson's IQ circulates as 109 and 121. A 2023 journal paper reports both from his files, names no test, and prints his 1997 scores. See the trail.
IQ OutcomesDoes practice beat IQ? What the 10,000-hour rule and the meta-analyses found
Practice explained 26 percent of performance differences in games and under 1 percent in professions across 88 studies. See each domain and where IQ enters.
Professional TestsArealMe IQ test reviewed: a free score compared with its own users
ArealMe IQ test review: free, 49 or 119 questions, scored against 7,563 recent Quick records, not a population. Terms and certificate read October 20, 2026.
ArticlesVerbal IQ and Performance IQ on an old report, and what replaced them
The WAIS-IV (2008) dropped Verbal IQ and Performance IQ, and Pearson says to read VCI and PRI. The history, the factor evidence and how to read an old report.
Famous IQTed Bundy's IQ: the 136 and the 124 that circulate
Ted Bundy's IQ circulates as 136 and as 124. Follow each figure to its source, then read what federal court opinions wrote about his intelligence.
IQ OutcomesWhat IQ correlates with: eighteen correlations ranked by size and source
18 sourced correlations with IQ, from 0.82 for SAT scores to minus 0.09 for neuroticism, each marked observed or corrected. See which links are strong.
Professional TestsThe IQ test in Canada: Mensa, psychologists and online options, with costs and the norms question
Mensa Canada charges 90 dollars and asks for the 98th percentile. Compare Mensa, a clinic fee of 800 dollars and ACIS, with prices read October 13, 2026.
ArticlesIQ vs the UCAT: is it an intelligence test, and why Abstract Reasoning was dropped
No study we found pairs UCAT scores with IQ. The 2025 UCAT dropped Abstract Reasoning for lower predictive validity. See the evidence and why no score converts.
Famous IQJoseph Stalin's IQ: the numbers that circulate and the 1936 test ban
Stalin's IQ appears as 120, 140 and over 250, yet no test is on record. A July 4, 1936 Central Committee resolution condemned tests. Each number traced.
IQ OutcomesWhat can lower your IQ, and what only lowers a single test score
Lead showed a 6.9 point IQ gap in pooled cohorts, while sleep loss and anxiety change a test day, not ability. Eleven exposures ranked by their best study.
Professional TestsThe IQ test for seniors: what a normed score after 60 can and cannot tell you
Adult norms reach age 90 on the WAIS-5 and ACIS, yet vocabulary peaks late and speed early. See which test suits a senior, what each costs and how to read it.
ArticlesIQ vs the GED: what a credential test measures, and what the research found
A 145 passes each GED subject on a 100 to 200 scale and is not an IQ. What Heckman, Humphries and Mader and a 2019 IQ study found, and why no conversion exists.
Famous IQGalileo Galilei's IQ: the 145 and 165 that Cox rated, and the 185 nobody can source
Catharine Cox rated Galileo 145 as a youth and 165 by age 26 from one biography. The 185 online has no test. Trace each figure, then read what his works record.
IQ OutcomesAre left-handed people smarter? What the meta-analyses actually found
A meta-analysis of 18 studies and 20,442 people found left-handers about 1 IQ point lower, a gap that vanished without the largest study. Every study sorted.
Professional TestsThe IQ test for non-native English speakers: what your English moves and what it leaves alone
Language ability shapes cognitive test scores (Cormier et al., 2022). Compare psychologists, Mensa and ACIS, with prices read October 13, 2026, and what to buy.
ArticlesHow big a gap between index scores is actually unusual
In a WAIS-IV simulation, 49 percent of normal profiles had a 15 point gap between some pair of the four index scores. See how to tell a real gap from noise.
Famous IQFriedrich Nietzsche's IQ: the 165 credited to Cox and the record that exists
Nietzsche's IQ is posted as 165, 190 and 144, yet Cox's 1926 volume never rated him. Trace each figure, then read the Pforta, Leipzig and Basel record.
IQ OutcomesThe IQ of politicians: what conscript tests and college records show
Swedish MPs scored about 0.84 standard deviations above the male population on a conscript test; US lawmakers have no test, only schools. Every study sorted.
Professional TestsThe IQ test for former gifted kids: why your not your number now
Age 11 to 77 scores correlated .63 in Deary's follow-up, so a gifted label is not a fixed number. See why it moves and which adult test to take, with costs.
ArticlesHow IQ tests are made, from blueprint to norms
The SB5 revision took 7 years and normed 4,800 people. See how IQ tests go from blueprint to norms in WAIS-5, SB5 and WJ V records, and what a quick test skips.
Famous IQBatman's IQ: the 192 that circulates and what DC actually publishes
DC's character page gives Batman no IQ, yet 192 circulates. Trace the figure through fan wikis and CBR, then see why 192 would sit 6.13 standard deviations up.
IQ OutcomesConspiracy beliefs and IQ: a weak link, and what each study measured
A 2023 Psychological Bulletin meta-analysis puts IQ and conspiracy belief at minus 0.16, but the theory chosen changes the result. Each study sourced.
Professional TestsThe IQ test for college students aged 18 or older: what to take, what it costs and how to read the number
A 2024 meta-analysis of Wechsler samples puts the average undergraduate near 102. See what each test route costs and how a student should read the score.
ArticlesDefinitions of intelligence: what experts share and where they split
No single definition of intelligence is agreed. Compare Wechsler, the 1994 statement signed by 52, the 1996 APA report, Legg and Hutter, and what IQ covers.
Famous IQShakespeare's IQ: a 210 with no test, no case history
Shakespeare's IQ circulates as 160 to 210 with no test behind it. Trace each figure, Cox's 1926 index entry and the 31,534 words Efron and Thisted counted.
IQ OutcomesStress, trauma and IQ: what the studies show about measured ability
Foster care raised IQ 9 points at age 18 in a randomized trial; adjusted birth cohorts and a lab stress test found near zero. Every design sorted and sourced.
Professional TestsThe Woodcock-Johnson V, read from its own documents: 20 cognitive tests, the clusters they build and who gives them
The Woodcock-Johnson V (Riverside, February 2025) has 20 cognitive tests. Riverside counts 12 clusters, a peer review 17. See the tests, CHC map and changes.
ArticlesQuantitative reasoning test: what the name covers, what a battery scores, and how to read the index
Fluid reasoning correlates .41 with math achievement in a 680 study meta-analysis. See where quantitative reasoning ends, Gq begins, and how a QRI reads.
Famous IQWhat Warren Buffett said about IQ, traced to the record
No IQ score of his own is on record. Buffett named 125 in 2005, 150 in 2009 and 160 in 2011 as points to sell, and the 160 versus 130 line is traced.
IQ OutcomesPsychopathy, narcissism and IQ: what the meta-analyses actually found
The evil genius test: 48 samples and 143 studies find no Dark Triad IQ edge; psychopathy is near r = -.07. See offender and community samples apart.
Professional TestsWAIS-5 subtests, task by task: what each one asks and which scores it feeds
Pearson lists 20 WAIS-5 subtests, 10 primary and 10 secondary, and only 7 build the Full Scale IQ. See what each task asks and which scores it feeds.
ArticlesThe Pygmalion effect and IQ: the 1968 claim, the critiques, and what survives
In the 1968 Pygmalion study, 7 first graders gained 15.4 IQ points more than controls. Raudenbush pooled 18 experiments to d 0.11. See what the record shows.
Famous IQWhat Thomas Edison's 163-question test really measured
Edison left no IQ score. Lists print 145 to 235. His 1921 questionnaire had 163 questions and a 70 percent pass mark that 57 of 718 men beat. See the sources.
IQ OutcomesPoverty and IQ: what cash trials and adoption show
Does poverty lower IQ? A randomized trial gave 1,000 mothers 333 or 20 dollars a month, then dropped its planned IQ outcome. See each design and effect size.
Professional TestsRIOT IQ test reviewed from its own pages: plans, norms and what the margin covers
RIOT IQ Full costs 50 dollars, and an outside analysis finds 3 of its 6 index scores not separable. Plans, norms, refunds and margins, read October 6, 2026.
ArticlesTurning a percentile into an IQ score, and where the conversion breaks
The 98th percentile is an IQ of 130.8 and the 90th is 119.2 on SD 15, by normal curve arithmetic. Tables for SD 16 and 24, top shares and report bands.
Famous IQRamanujan's IQ: the 185 that circulates and the record Hardy left
Ramanujan never took an IQ test. Trace the 185, then read Hardy's reported 100 against his own 25, the 1913 letter, the 1729 story and the 1918 election.
IQ OutcomesDo night owls score higher? A small association and what the hour changes
Night owls scored 13.5 percent higher in 2024 headlines, yet the paper reports 0.1351 on a z-score scale. See every study, its confounds and the effect size.
Professional TestsReporting IQ in research: the eight facts a score hides
How to report IQ in a research paper: eight facts to state, from APA JARS-Quant and the 2014 Standards, and why 2007 to 2008 norms add points (2.31 per decade).
ArticlesIQ vs the MCAT: what the score measures, what it predicts and why no table converts it
AAMC ranks a 508 at the 74th percentile of 305,494 exams. No study we found paired the MCAT with IQ. See what it predicts and why no score converts.
Famous IQMozart's IQ: the 150 that circulates and what the childhood record shows
Mozart's IQ circulates as 150, 155 or 165, but no test exists. Read the three 1926 ratings, Barrington's 1770 report and Leopold's letters from Rome.
IQ OutcomesIQ and relationships: partners match, but only partly
Partners correlate 0.44 in IQ across 17 samples but 0.23 in UK Biobank. See what that means for marriage, divorce, dating and looks, study by study.
Professional TestsOnline cognitive testing data quality: who you recruit changes the data more than the task does
Who you test changes cognitive data: stricter attention checks excluded about 62 percent of MTurk and 22 percent of Prolific takers. See the studies and rules.
ArticlesIQ vs the bar exam: what each part measures, what predicts passing and why no score converts
Final law GPA explained 51.5 percent of bar score variance and the LSAT 12.5 percent (Texas Tech, Hofstra Law Review). No bar study reviewed here measured IQ.
Famous IQLady Gaga IQ: the 166, the Quora answer and the documented record
Lady Gaga's IQ is listed as 166 with no test behind it. See which pages print the figure, what the 'hard proof' article rests on, and what her record shows.
IQ OutcomesIQ and fertility: what registers and surveys count
Swedish registers of 779,146 men found more children at higher IQ; US surveys found fewer, most clearly for women. Each study, its design and the arithmetic.
Professional TestsIQ test apps compared: what the store listings charge, claim and leave out
14 IQ test apps read on October 6, 2026: prices from 0.99 to 99.99 dollars, trial and renewal rules, and what research says a phone does to a timed score.
ArticlesThe IQ distribution, band by band, and where real scores depart from the curve
Percent and people per million in each 5 point IQ band from 55 to 145, plus what Micceri's survey of 440 psychometric measures found about real tails.
Famous IQJensen Huang IQ: the transcript, the 180 and the documented record
Jensen Huang's IQ is listed as 180 or 185 with no test behind it. See the Ezra Klein transcript behind the 'low IQ era' quote and his documented path.
IQ OutcomesIQ and entrepreneurship: what studies of founders, the self-employed and CEOs measured
Swedish conscript records put the median large-firm CEO in the top 17 percent for cognitive ability. See what founder, CEO and self-employment studies measured.
Professional TestsIntelligence measures for online studies, from 16 items to a full normed battery
ICAR16 reports alpha 0.81 on 16 items and the Hagen Matrices Test 0.78 in about 25 minutes. Compare 10 intelligence measures for online studies by cost.
ArticlesIntelligence from mother or father: the X chromosome claim against the family studies
Is intelligence from the mother's X chromosome? A review of 111 family studies found IQ correlations of .41 for mothers and .41 for fathers. See the sources.
Famous IQGoethe's IQ: the 210 that circulates and what the 1926 ratings show
Goethe's IQ is cited as 210, yet 1926 ratings print 185 and 200, reliability .82. Trace the 210 and one judge's 225, then read his childhood record.
IQ OutcomesEnvironmental toxins and IQ: what each exposure shows, study by study
A 2022 model put US lead losses at 824 million IQ points. See what cohorts show per child for lead, air, pesticides, mercury and fluoride, with sources.
Professional TestsInnerly IQ test reviewed: the entry price, the renewal and what the score rests on
Innerly IQ test review: 0.99 dollar entry, 39.99 dollars monthly after 3 days, 480.87 dollars in 12 months, plus cancel and refund terms read October 6, 2026.
ArticlesWhere intelligence sits in the brain: what imaging studies replicate
Intelligence maps to a distributed parieto-frontal network, but brain-wide effects are small (median r = 0.01). See the effect sizes and what replicates.
Famous IQCharles Darwin's IQ: Cox's 135 and 140 beside his own words
Darwin's IQ circulates as 165 or 140 plus, but no test exists. Cox's 1926 table prints 135 and 140 on thin records. See her figures beside his own words.
IQ OutcomesAverage IQ by military branch: what the official data shows
No branch publishes an average IQ. DoD data for fiscal 2023: 79.8 percent of Air Force recruits scored AFQT 50 or higher, against 52.1 percent in the Army.
Professional TestsCogniProfile IQ test reviewed from its own pages: price, terms, what is missing
CogniProfile IQ test review: a 1.99 dollar 7 day trial, then 20 dollars a month in its payment screen code, plus cancel and refund terms, read October 6, 2026.
ArticlesCollective intelligence: is there a group IQ, or is it the members' IQ?
In 2010 a c factor carried 43 percent of group task variance. A 2017 study found member IQ explained about 80 percent. Both sides, with their own figures.
Famous IQAlan Turing's IQ: the 185 that circulates and the record that exists
Alan Turing's IQ is cited as 185, but no test, date or examiner is on record. Trace the number, then read his 15 Sherborne reports and the 1936 paper.
IQ OutcomesAverage IQ by gender: what the means, the spread and the tails actually show
Calvin and colleagues found a 0.01 standard deviation mean gap and a male variance ratio of 1.16 in 178,599 English pupils. See every study, tail and domain.
Professional TestsThe adaptive IQ test, explained: how a test picks its questions, when it stops and what it costs
An adaptive IQ test picks each item from your answers. The NIH Toolbox stops at a standard error of 0.3, CAT-ASVAB at 15 items. See what that gains and risks.
ArticlesA low IQ: where the scale draws its lines at 85 and 70, and what the number cannot say
A low IQ often means below 85 on the SD 15 scale. Learn what scores near 70 can indicate, why diagnosis needs more evidence, and how to read a low result.
Famous IQNapoleon IQ: what Cox estimated and what history can establish
Napoleon had no administered modern IQ test. Cox's 1926 case study gave retrospective estimates of 135 and 140; neither is a measured cognitive score.
IQ OutcomesAverage IQ in Germany: the figures and what their samples measure
German IQ norms center near 100; historical and online sources report 100.61 and 99.32. Compare their samples with German adult skills and PISA evidence.
Professional TestsAn IQ test in the UK: the four ways to get a score, what each costs in pounds, and which ones count
Compare UK IQ testing routes: British Mensa, private psychologists, NHS assessment and online batteries, with prices, evidence and practical acceptance checks.
ArticlesSpatial intelligence: the ability behind the term, the tests that measure it, and what training changes
Spatial intelligence involves visualizing and transforming shapes. Read how it is measured, what training studies show, and how to interpret a spatial score.
Famous IQMichael Jackson IQ: musical achievement and unverified score claims
Michael Jackson's alleged IQ scores of 159 and 164 lack verified test evidence in this review. Read the documented achievements and music research.
IQ OutcomesAverage IQ in Australia: which sample and which scale?
Average IQ in Australia depends on the sample and scale. Compare Australian and NZ norms, historical estimates, online rankings and representative surveys.
Professional TestsA processing speed test for adults: what the PSI measures, and how to take a normed one online
Learn how processing speed tests measure timed performance, how age norms and uncertainty affect a PSI, and when online testing or clinical assessment fits.
ArticlesIQ levels: how classification systems name the same score differently
IQ levels depend on the test and its edition. Compare classification labels, understand the 100 and 15 scale, and read boundaries with measurement error.
Famous IQMarilyn Monroe IQ: what the evidence says about the 168 claim
Marilyn Monroe's alleged IQ of 168 has no verified test record in the sources reviewed. Examine her library, writing, acting archives and the claim.
IQ OutcomesChess and IQ: a modest correlation, expert knowledge and what training changes
Chess skill and cognitive ability correlate about 0.22 in a corrected meta-analysis. Learn why ratings cannot reveal IQ and what chess training studies show.
Professional TestsWhat is my IQ? Choose a test that answers your actual question
Find out your IQ with a test suited to your purpose. Compare professional, Mensa and documented online routes, costs, reports and measurement uncertainty.
ArticlesIQ 140: how rare the score is and how to interpret it
IQ 140 is about the 99.62nd percentile, or 1 in 261, on an SD 15 scale. Understand the calculation, confidence interval, profile and limits of the score.
Famous IQJFK IQ: the reported school score and the evidence behind it
JFK's IQ is reported as 119 by biographer Thomas Reeves. Learn why that claim, the 159.8 research estimate and a presidential IQ hoax are different.
IQ OutcomesAverage IQ in Canada: how norms change the meaning of a score
Canadian IQ norms center near 100; one norm sample averaged 104.51 on US tables. Examine that comparison, country estimates and provincial skills data.
Professional TestsThe WAIS-IV, read from the record form to the report: subtests, scores and the General Ability Index
The WAIS-IV (Pearson, 2008) scores 10 core subtests into four index scores and an FSIQ of 40 to 160, normed on 2,200 adults aged 16 to 90. Every table sourced.
ArticlesGifted adults: what the research says about ability after childhood
Gifted adults are often defined by scores near 130, but traits are not a diagnosis. Read the evidence on identification, assessment, work and mental health.
Famous IQChristopher Hirata IQ: tracing 225 and the documented science
Christopher Hirata's IQ is often listed as 225. A 2001 profile calls it an estimate; his degrees and physics achievements have a stronger documented record.
IQ OutcomesAverage IQ in the USA: compare the numbers and the samples behind them
US IQ norms center near 100; 97.50 and 101.04 come from different samples. Learn what the national figures, state estimates and adult skills data measure.
Professional TestsCognitive Metrics reviewed: what a free CORE, CAIT or AGCT score can and cannot tell you
Cognitive Metrics reviewed through CORE documentation, norms, reliability, prices and limits. What its free tests support and what needs stronger evidence.
ArticlesIQ 100: the exact middle of the scale, and what follows from it
Is an IQ of 100 good? It is the exact mean of the norm sample, the 50th percentile, inside the 90 to 109 Average band, and really an interval of 97 to 103.
Famous IQBobby Fischer's IQ: a number from one biography, and a record from the board
Bobby Fischer's IQ of 181 traces to a secondhand anecdote in a 1965 biography naming no test or examiner. The record: US champion at 14, world title in 1972.
IQ OutcomesAnxiety and IQ: what anxiety does to a score, and what a score says about anxiety
Does anxiety affect IQ? It lowers working memory performance by a third of a standard deviation across 22,061 people; higher childhood IQ predicts less anxiety.
Professional TestsWonderlic score to IQ: the conversion chart, where it comes from, and where it breaks
Convert a Wonderlic score to IQ: 20 maps to about 100 and each point adds about 2 IQ points on a .93 correlation with the WAIS. The 0 to 50 chart and limits.
ArticlesWhat is IQ? A standard score, a scale, and what the number means
IQ stands for intelligence quotient: a standard score placing your test result against a reference sample, mean 100 and standard deviation 15. What it means.
Famous IQShakira's IQ of 140: a list Mensa never published, and a record you can check
Shakira's IQ of 140 comes from a June 2013 report of a Mensa celebrity list that Mensa said it never published. No test exists. What is documented instead.
IQ OutcomesReading and IQ: what the twin study, the meta-analyses and the long follow ups show
Does reading increase IQ? In 1,890 identical twin pairs the twin who read better at 7 scored higher on intelligence later, verbal and nonverbal. The evidence.
Professional TestsNeuropsychological testing for adults: what it includes, what it costs, and when an IQ test is enough
Neuropsychological testing for adults costs 3,500 to 7,000 dollars privately or about 300 at a university clinic. What it covers and when an IQ test is enough.
ArticlesWhat is a cognitive test? A standardized sample of mental performance, scored against a reference group
A cognitive test is a standardized sample of mental performance scored against a reference group: IQ batteries, dementia screens, neuropsych and job tests.
Famous IQWilliam James Sidis's IQ: an estimate from 1946, and a record from 1910
No IQ score for William James Sidis exists; the 250 to 300 is a 1946 estimate by a writer who never tested him. The record: Harvard at 11, a book at 27.
IQ OutcomesSocial media and IQ: what the studies measure, and what they do not
Does social media lower IQ? No study shows it. The 9,855 child ABCD analysis found no effect of online socializing on intelligence; sleep is the real cost.
Professional TestsThe Mensa Norway IQ test: what it measures, how it scores, and what it leaves out
Mensa Norway's free test is 35 visual puzzles in 25 minutes, scored 85 to 145 in four age bands, with no published norms or reliability. What a score tells you.
ArticlesChatGPT IQ: what happens when a language model sits an IQ test, and what the number means
What is the IQ of ChatGPT? A Verbal IQ of 155 on WAIS subtests, Mensa charts in the 150s, a bar exam in the top 10 percent: what each was compared with.
Famous IQYoungHoon Kim's IQ of 276: who certified it, and what no test can measure
YoungHoon Kim's 276 IQ was certified by a memory sports council and a records company, not a test publisher; no normed test scores above 160. What 276 means.
IQ OutcomesThe average IQ in the UK is 100, and the reason is the ruler
The UK's average IQ is 100 because British norm samples define the scale. Becker's dataset gives 99.66, online tables 101.6, PISA 2025 puts England above OECD.
Professional TestsA working memory test for adults: what it measures, and how to take a normed one
A real working memory test uses span tasks like digit span scored against age norms, not a two minute game. What each task measures and how to read a WMI score.
ArticlesIs IQ real? A statistical regularity, a valid measurement, and an open causal question
Is IQ real? The general factor replicates across batteries at .95 to 1.00, holds from age 11 to 77 at r = .63, and predicts school, work and death. Critiques.
Famous IQMarilyn vos Savant's IQ: the 228, the 186, and what each one measured
Marilyn vos Savant's 228 IQ is a ratio score from a 1937 Stanford-Binet taken at age 10, not a modern score; the 186 is a Mega Test extrapolation. Explained.
IQ OutcomesThe average IQ in India: three numbers, and what the samples show
India's average IQ is quoted as 76, 82 or 98 depending on the dataset. The 76 rests on 20 convenience samples of children, none representative. What each means.
Professional TestsAn official IQ test: what the word actually covers, and where to take one
No single official IQ test exists. Three routes count: a psychologist with the WAIS-5, a supervised Mensa session, or a normed online battery. Costs of each.
ArticlesThe fluid intelligence test and the four tasks that measure it
Fluid reasoning is the most g loaded of the six ACIS domains at .922. Here are the four task families that measure it, worked examples, and what a score means.
Famous IQAdolf Hitler's IQ: the score that was never taken
Hitler died before the trials and was never tested, so no score exists. Gilbert's 1947 Nuremberg Diary prints 21 Wechsler-Bellevue figures, 143 down to 106.
IQ OutcomesAverage IQ by birth month and the relative age effect
No month produces higher ability. The oldest children in a school year outscore the youngest by a measurable margin, and the effect depends on the entry cutoff date.
Professional TestsThe hardest IQ test and the arithmetic of difficulty
A test built only from hard items measures almost nobody well. Here is how item difficulty is set, how ceilings are actually built, and what hardness costs.
ArticlesVerbal IQ testing and the index that replaced it
No current Wechsler scale reports a Verbal IQ. What replaced it is an index built from five task families, and this is what each one isolates and what it misses.
Famous IQNatalie Portman's IQ: the Strongest Record in Acting, and Still No Score
The Natalie Portman IQ of 140 is unsourced. What is documented is two peer reviewed papers published under the name Natalie Hershlag and a Harvard psychology degree.
IQ OutcomesHumor and measured ability
Humor production correlates .49 with verbal ability and .22 with fluid reasoning across 270 adults. Appreciating a joke is a different task with different evidence.
Professional TestsBRGHT IQ test: adaptive design, self-anchored norms
BRGHT runs 40 adaptive items in 30 minutes and scores you against its own 1,485,900 finishers. The design is good, the reference frame is the problem.
ArticlesThe General Ability Index, and what it leaves out
The GAI drops working memory and processing speed from the composite. Pearson lists the belief that this makes it a truer score as a myth, and explains why.
Famous IQSylvester Stallone's IQ: an Unsourced Number and a Record You Can Check
The Sylvester Stallone IQ of 160 names no test, no date and no examiner. What is documented is the Rocky screenplay of 1975 and two Academy Award nominations.
IQ OutcomesFluoride and IQ: what the dose response shows
The association appears above 1.5 mg per litre. Below it the evidence thins and the two best cohorts in fluoridated countries found nothing. Every study, sourced.
Professional TestsThe quick IQ test and what it costs
Cutting a test's length widens its error band by a formula published in 1910. Here is what a five minute test can measure, and the shortest form that still norms.
ArticlesThe Cognitive Reflection Test and its three answers
The three original CRT items with the intuitive answer and the correct one worked step by step, plus the sample means, the correlations, and the contamination.
Famous IQJoe Biden's IQ and the record that actually exists
No IQ score exists for Joe Biden. What exists is a 65 page academic file he released in 1987, and a cognitive screen that was never an intelligence test.
IQ OutcomesMusic taste and intelligence
The classical music finding is real, small, and about instrumental versus vocal music. Here is every study with its sample, effect size, and confound in one table.
Professional TestsThe Stanford-Binet online
The SB5 is a Level C instrument sold as a 1,422 dollar kit and administered face to face. Here is what the sites selling a Stanford-Binet online are really charging for.
ArticlesHow an IQ score is actually calculated
An IQ score is built in nine steps, from credit on one item to a confidence interval. The mental age formula has not been used by a major test since 1960.
Famous IQFictional characters with the highest IQ
Sheldon Cooper and Spencer Reid are both written at 187, which is 5.8 standard deviations out and about one person in 302 million. Every canon number, sourced.
IQ OutcomesAverage IQ by university
A 106 sample meta-analysis puts the average undergraduate at 102, not 115. Here is the selectivity band table, the method behind it, and why named numbers fail.
Professional TestsPaid IQ tests and the billing model behind them
Four billing models sit behind paid IQ tests, and one of them costs 780 dollars a year. Here is what each charges over 12 months, with prices read in September 2026.
ArticlesIQ Score vs Percentile: The Same Fact in Two Languages
Percentiles are not an interval scale, so they cannot be averaged or subtracted. How the conversion works and where it breaks.
Famous IQJD Vance's IQ: No Score Exists, and the Category Is the Least Reliable of All
No cognitive result exists for any officeholder. The most quoted table of presidential IQs came from an institute that never existed.
IQ OutcomesAverage IQ by Language: Why the Question Breaks, and What Language Really Does
Language does not change ability and heavily changes measured scores. On one subtest the effect is pure syllable length.
Professional TestsHigh IQ Society Requirements: Thresholds, Accepted Tests, and What Actually Gets You In
Entry thresholds compared, which tests each accepts, and why supervised administration is the one requirement no online score can meet.
ArticlesThe Subtests Inside an IQ Test: What Each One Is Actually For
An IQ score is built from subtests, each targeting one narrow ability. Every major subtest type, its confounds, and why single scores mislead.
Famous IQVitalik Buterin's IQ: No Score, an Olympiad Medal, and What That Explains
No cognitive result has ever been published and some circulating figures are impossible. What his documented record establishes.
IQ OutcomesAverage IQ by Sport: One League Actually Collected Data. Here Is What It Showed
Almost no sport tests its athletes. American football did for decades, and the result was so unremarkable the league dropped the test.
Professional TestsThe Adult IQ Testing Process: From First Enquiry to Final Report
What happens from referral to report: who administers it, how long it takes, what it costs, and what you actually receive.
ArticlesWhy IQ Tests Are Timed: A Measurement Decision, Not a Gimmick
Time limits are a measurement decision, not a gimmick. Speed tests, power tests, time bonuses, and when an untimed score means something else.
Famous IQChristopher Langan's IQ: Where the 195 Came From, and What It Actually Shows
Untimed, unsupervised, and normed on volunteers who chose to enter. What the smartest man in America case really demonstrates.
IQ OutcomesAverage IQ by Generation: Rising, Stalling, and What That Actually Means
Raw scores climbed 30 points across a century and have since reversed in several countries. What the Flynn effect does and does not show.
Professional TestsWAIS-IV vs WAIS-5: What Actually Changed, and Whether It Matters to You
The 2024 revision split one index in two and rebuilt the norms. Same performance, lower score, and a threshold you may now cross.
ArticlesProcessing Speed: The Ability Everyone Underestimates
Gs is the first ability to go and the most sensitive to injury. What it predicts, how it is measured, and why the tasks look so easy.
Famous IQMagnus Carlsen's IQ: The 190 Has No Source. The 2882 Does
The 190 has no source. His chess rating is a better validated measurement than any cognitive test, and it only measures chess.
IQ OutcomesAverage IQ by College Major: What the Rankings Are Really Built From
Physics and philosophy top the list, and the ordering is about who applies, not what studying does. Where the numbers actually come from.
Professional TestsHow to Prepare for an IQ Test: What Helps, What Does Nothing, What Ruins It
Sleep and format familiarity help. Practising items invalidates your score. Evidence-based preparation with a day-by-day timeline.
ArticlesCan You Improve Your IQ? Yes, and the Question Is Which Ability
Schooling raises measured IQ 1 to 5 points a year; training moves the tasks it resembles. What transfers, what is only practice, and what never reaches g.
Famous IQTerence Tao's IQ: The 230 Claim, and What Is Actually Documented
No instrument reaches that range and no assessment was ever published. What his olympiad and academic record actually documents.
IQ OutcomesAverage IQ by State: Where the Numbers Actually Come From
No state has ever been IQ tested. Every ranking is school achievement data converted, and the spread is smaller than one person's error bar.
Professional TestsIQ Test Certificates: What They Are Actually Worth
No body accredits IQ certificates. What schools, employers, and societies actually require, and what documents a cognitive assessment properly.
ArticlesIQ vs GRE: Overlap Without Conversion
IQ vs GRE explained through official score scales, percentiles, verbal and quantitative reasoning, preparation, correlation and conversion limits.
Famous IQLionel Messi IQ: No Verified Number
Messi has never been tested, yet football intelligence is a real research field. See what scanning and anticipation studies actually measure, and what they do not.
IQ OutcomesBirth Order and IQ: Small Effect, Large Overlap
Birth order and IQ research explained through three national panels, small firstborn differences, family confounding and individual overlap.
Professional TestsIQTest.com Review: What Does $19.95 Buy?
IQTest.com review covering its free general score, $19.95 Complete Intelligence Profile, evidence, report claims, privacy and ACIS comparison.
ArticlesCritical Thinking vs Intelligence: Capacity and Use
Critical thinking vs intelligence explained through cognitive ability, rationality, knowledge, thinking dispositions, bias and real-world decisions.
Famous IQJoe Rogan IQ: What 127 Means
Rogan's 127 comes from a paid online test he took and shared, whose own terms disclaim validity. See why unproctored results run high, and what that means.
IQ OutcomesExercise and IQ: Promising, Not Guaranteed
Exercise and IQ evidence explained through 14 randomized trials, youth results, fluid intelligence, heterogeneity and limits on permanent gains.
Professional TestsTest-IQ.org Review: Certified Does Not Mean Clinical
Test-IQ.org review covering BMI Certified IQ Test, $29.99 Access Pass, auto renewal, report, validity disclaimers and ACIS Full comparison.
ArticlesAptitude vs Intelligence: Specific vs General
Aptitude vs intelligence explained through specific abilities, general cognitive ability, achievement, prediction, hiring, education and test use.
Famous IQMrBeast IQ: Unknown, Not Estimated
No test appears anywhere in MrBeast's public record, yet figures circulate anyway. See the assembly line that manufactures them, and what his method shows.
IQ OutcomesSleep and IQ: Performance Is Not a Fixed Ceiling
Sleep and IQ research explained through child cohorts, deprivation, cognition, confounding, test-day performance and stable intelligence limits.
Professional TestsInternational IQ Test Review: What 16M Results Do Not Prove
International IQ Test review covering its matrix format, 16M result database, score methodology, limitations, report and comparison with ACIS Full.
ArticlesIntelligence vs Knowledge: Capacity and Content
Intelligence vs knowledge explained through reasoning, learning, crystallized ability, expertise, memory, education and what IQ tests actually measure.
Famous IQJordan Peterson IQ: Claim vs Record
The figure above 150 traces to Peterson recalling it himself, with no report or date. His academic record is verifiable; the number is not. See both.
IQ OutcomesIQ and Crime: Association Without Moral Ranking
IQ and crime research explained through cohort evidence, confounding, verbal and spatial scores, detection, effect size and ethical limits.
Professional TestsCerebrum IQ Test Review: Read the Terms First
Cerebrum IQ test review covering its $0.99 trial, recurring subscription, score evidence, report, cancellation and comparison with ACIS Full.
ArticlesAre IQ Tests Biased? Six Questions, Not One
Are IQ tests biased? Learn the difference among test bias, DIF, cultural loading, group differences, access, validity and fair score use.
Famous IQDolph Lundgren IQ: Is 160 Verified?
The 160 has followed Lundgren since 2012 without naming a test, and he has said he does not know his score. His Sydney masters and MIT Fulbright are real.
IQ OutcomesBreastfeeding and IQ: Association Is Not the Whole Answer
Breastfeeding and IQ research explained through meta-analyses, maternal IQ, sibling comparisons, randomized evidence and individual limits.
Professional TestsMyIQ IQ Test Review: Evidence Before Payment
MyIQ IQ test review covering its 40 questions, $1 trial, $29.99 per 28 day renewal, score evidence, cancellation and a disclosed ACIS comparison.
ArticlesIntelligence vs Wisdom: Ability Is Not Judgment
Intelligence vs wisdom explained with meta-analytic evidence. Compare IQ, judgment, crystallized ability, life problems and whether wisdom can grow.
IQ OutcomesIQ and Musical Ability: Overlap, Not Destiny
IQ and musical ability overlap, but training, aptitude and practice remain distinct. See twin data, verbal links, transfer evidence and myths.
Professional TestsBrainable IQ Test Review: 15/50
Brainable IQ test review: 15/50. See its 20 questions, three games, subscription model, brain training claims, accuracy limits and alternatives.
ArticlesIQ vs GMAT: Related, Not Equal
IQ vs GMAT using the current 205 to 805 scale. Compare Quant, Verbal, Data Insights, percentiles, preparation and exact conversion limits.
Famous IQSnoop Dogg IQ: 147 Is Unverified
The 147 started as a social media graphic that Snoop reposted, which is its entire evidentiary base. See what his documented business record does support.
IQ OutcomesIQ and Height: Small Correlation
IQ and height correlate slightly, around r = 0.16 in one major study. Learn shared genetics, development, causality and why height cannot predict IQ.
Professional TestsOpenPsychometrics IQ Test Review
OpenPsychometrics IQ test review. See its six sections, free results, three domains, accuracy warning, evidence gaps and best uses.
ArticlesIQ vs LSAT: Related, Not Equal
IQ vs LSAT explained using the current 120 to 180 scale and post-2024 format. Learn correlation, percentiles, validity and conversion limits.
Famous IQGarry Kasparov IQ: 135 and 123
Der Spiegel tested Kasparov in Baku in 1987 and published 135, plus 123 on Raven's. It is the rare celebrity figure with a date, a magazine and a method.
IQ OutcomesIQ and Video Games: Small Association
IQ and video games show a small positive association, but causal IQ gains are unproven. See meta-analyses, genres, transfer and selection effects.
Professional TestsIQ Test Academy Review: What You Can Verify
IQ Test Academy review: what iqtestacademy.org publishes about its test, what it does not disclose, reported pricing, and how to tell near identical sites apart.
ArticlesIQ vs ASVAB: AFQT Is Not IQ
IQ vs ASVAB explained: AFQT percentiles, subtest scores, cognitive overlap, conversion limits, line scores, preparation and official uses.
Famous IQNeil deGrasse Tyson IQ: No Verified Number
Tyson has refused to publish a score for years, so every figure attached to him was supplied by someone else. See what he has said and what is documented.
IQ OutcomesIQ and Religion: What Research Shows
IQ and religion show a small negative average correlation, about r = -0.14. Learn effect size, causality limits, measures, moderators and overlap.
Professional Tests123test IQ Test Review
123test IQ test review comparing its free demos and paid tests across evidence, norms, report depth, security, price and precision. Verdict: 23/50.
ArticlesIQ vs ACT Score
IQ vs ACT scores overlap but are not interchangeable. Compare constructs, current 1 to 36 scoring, percentiles, preparation and conversion limits.
Famous IQJ. Robert Oppenheimer IQ: No Verified Score
Figures from 135 to 160 circulate for Oppenheimer with no administration behind any of them. See how to audit a historical claim in about ten minutes.
IQ OutcomesIQ and Political Orientation
IQ and political orientation show small, context dependent group associations. Review party identity, social attitudes, authoritarianism, causes and limits.
Professional TestsBrainManager IQ Test Review
BrainManager IQ test review using a 50 point rubric. Examine its score, evidence, report, trial, subscription terms and better alternatives.
Famous IQRichard Feynman IQ: 125 With Context
Feynman's reported 125 is real, and lower than most expect from a Nobel laureate. See which test produced it, why it is unnamed, and what it does not settle.
ArticlesHow long an IQ test takes, instrument by instrument
Real administration times from the publishers: 45 minutes for the WAIS-5 FSIQ, about 50 for the Stanford-Binet 5, and 45 to 175 for the three ACIS tiers.
Famous IQCelebrities With the Highest IQ: Where Each Number Came From
Every famous IQ figure sorted into four evidence classes: documented test, documented proxy, published expert estimate, or unsourced folklore. Most are folklore.
IQ OutcomesAverage IQ by Personality Type, and Why the Table Comes Out Flat
Average IQ by personality type, with the real meta-analytic coefficients. Why type is the wrong unit, what Openness actually predicts, and the honest upper bound.
Professional TestsThe ICAR Test and the Percentile It Cannot Give You
The ICAR test is a public domain cognitive battery. What ICAR 16 and ICAR 60 measure, whether they are timed, and why an ICAR score has no IQ percentile.
ArticlesGenius IQ and the 140 threshold
No test in use today has a genius band. The 140 line comes from one table in Terman's 1916 manual, and his own cohort data shows what it failed to predict.
Famous IQTwo presidents left a test score. The rest of the ranking is a statistical reconstruction
Only two presidents left a documented test score. The famous ranking of 42 comes from one 2006 study, and 34 of its numbers were reconstructed statistically.
IQ OutcomesAI and IQ: what the famous studies actually measured
No study behind the claim that AI makes you dumber has measured IQ. What Kosmyna, Gerlich and Lee actually tested, and what the evidence really supports.
Professional TestsWho Can Administer an IQ Test: Levels A, B and C
Full IQ batteries sit at Level C: doctorate, assessment training, licensure. See what psychologists, therapists, teachers and researchers may actually give.
ArticlesHow IQ changes with age: two answers, both true
Your rank among age peers barely moves across sixty years while raw performance rises and falls a lot. Both facts are true. Here is the evidence for each.
Famous IQRowan Atkinson's IQ: a Number With No Test, and a Record That Can Be Checked
The Rowan Atkinson IQ of 178 names no test, no date and no examiner. What is documented instead is an engineering BSc from Newcastle and an MSc from Oxford.
IQ OutcomesAphantasia and IQ: what the evidence actually shows
People without a mind's eye score at least as well on intelligence tests. What Zeman, Milton, Pounder and Bainbridge found, and why imagery is a strategy.
Professional TestsThe Real Cost of Cognitive Testing Platforms
What it costs to test other people: verified Q-interactive license and per subtest fees, WAIS-5 kit prices, examiner time and three worked totals.
ArticlesThe Dunning-Kruger effect and IQ: the real numbers
Self-estimated intelligence correlates about .33 with measured ability, and much of the Dunning-Kruger chart is regression to the mean. What the evidence shows.
Famous IQMuhammad Ali's army test was real. The IQ number attached to it was not
Muhammad Ali took a documented 1964 Armed Forces qualifying test and scored at about the 16th percentile. Why that percentile is not an IQ of 78 or 83.
IQ OutcomesCannabis and IQ: what the replication record actually shows
Does weed lower your IQ? The Dunedin cohort reported 8 points lost, then four genetically informed replications tested it. The full sequence, design by design.
Professional TestsCognitive Assessment Platforms, Sorted by What They Actually Answer
One phrase, four unrelated products. Compare Creyos, CANTAB, Cognitron, Mobile Toolbox, Gorilla, PsyToolkit, Pearson and ACIS by the question each answers.
ArticlesTypes of IQ tests: the instruments, one row each
Every major intelligence test in one inventory: publisher, edition, ages, administration mode and qualification level, verified on the publisher's own page.
Famous IQTed Kaczynski's IQ: a documented 136 and an unverified 167
The only documented figure is a WAIS-R Full Scale IQ of 136 from a 1998 federal court record. The viral 167 is an unverified childhood ratio score.
IQ OutcomesAlcohol and IQ: which way the causal arrow runs
Danish conscripts tested before and after show most of the IQ gap in heavy drinkers was already there. What alcohol does to the brain, and what it does not.
Professional TestsCreyos, reviewed by a company that sells a competing test
A review of Creyos, formerly Cambridge Brain Sciences: the 12 task battery, the Owen research pedigree, what pricing is and is not published, and who it suits.
ArticlesIQ vs SAT: Strong Overlap Does Not Make Them the Same Test
SAT and IQ scores overlap because both require cognitive skills, but they serve different purposes. Learn the correlation, differences and conversion limits.
IQ OutcomesIQ and Depression: A Score Is Not a Diagnosis or a Cause
High intelligence does not appear to cause depression. Learn how depressive symptoms can affect cognitive testing, what studies show, and when to seek help.
ArticlesMental Age: A Historical Score Unit, Not a Literal Mind Age
Mental age was a historical way to compare a child's test performance with age peers. Learn the formula, why it fails for adults and what modern IQ uses.
IQ OutcomesIQ and Happiness: Intelligence Is Not an Emotional Destiny
Research does not support the myth that intelligence guarantees happiness or misery. See how health, income, personality and social context shape the link.
ArticlesThe 10 Percent Brain Myth: Potential Is Not Dormant Brain Tissue
The claim that humans use only 10 percent of the brain is false. See what imaging, metabolism, lesions, networks and plasticity actually reveal.
IQ OutcomesIQ and Memory: Overlap Is Real, Identity Is Not
Learn how IQ relates to working, short-term, episodic, semantic and visual memory, why the overlap is real but incomplete, and what tests actually measure.
ArticlesPhotographic Memory: Exceptional Recall Is Still Not a Camera
Photographic memory is not a human camera. Learn the differences among eidetic imagery, HSAM, visual memory, trained mnemonics and ordinary reconstruction.
IQ OutcomesIQ and Personality: Related in Places, Separate in Meaning
Explore how IQ relates to Big Five personality traits, why most correlations are modest, where openness stands out, and why intelligence is not character.
ArticlesSavant Syndrome: Exceptional Skill Is Not a Single IQ Profile
Learn what savant syndrome means, how exceptional skills can coexist with uneven abilities, its relationship with autism, and why media stereotypes mislead.
IQ OutcomesTwice Exceptional: Strength and Disability Can Coexist
Learn what twice exceptional means, how giftedness and disability can mask each other, what assessment requires, and why one IQ score is not enough.
Famous IQJohn von Neumann IQ: Extreme Ability, Unmeasured Number
The 180 and 200 quoted for von Neumann were reconstructed from anecdotes. Standard batteries stop near 160, so a defensible range is 150 to 160.
Famous IQSam Altman IQ: 170 Is a Citation Loop
The 170 for Altman comes from estimate pages citing each other, with no instrument, date or examiner at the bottom. See what the public record supports.
Famous IQCristiano Ronaldo IQ: Football Genius Is Not a Number
Two confident figures, no instrument or date behind either, and the gap between them is the clearest sign neither was measured. See what the record shows.
Famous IQAndrew Tate IQ: A Self Report Is Not Verification
The 148 is a self report with no test, edition, date or examiner attached. See what the public record supports and where a defensible reading actually lands.
Famous IQBarack Obama IQ: The 145 Claim Is Not a Test Result
Follow the 145 and it ends at other celebrity lists, never at a test. The documented record is Columbia, Harvard Law and the Law Review presidency.
Professional TestsComprehensive IQ Test: Breadth You Can Verify
See what makes an IQ test comprehensive, which cognitive domains and report features matter, and how to compare serious online and professional options.
Professional TestsNonverbal IQ Test: Less Language, Not No Bias
Learn what a nonverbal IQ test measures, who it helps, where language still matters, and how to choose a serious online or professional assessment.
Professional TestsWAIS Test Online: What You Can Actually Take
Can you take a WAIS test online? Learn the difference between an official remote WAIS, public imitations, and a serious online IQ assessment for adults.
Professional TestsHigh Range IQ Test: Measuring the Extreme Upper End
A high range IQ test measures scores above the standard 160 ceiling. Most high range tests are unstandardized and inflate their numbers. ACIS is validated and its scale extends above 160, read with honest limits.
Professional TestsGifted Test for Adults: Confirm Where You Really Stand
A gifted test for adults measures whether your cognitive ability is in the gifted range, about IQ 130 and up, the top 2 percent. ACIS is validated, adult-normed, and its ceiling extends above 160, so it can measure inside the gifted range.
IQ OutcomesIQ and Longevity
Higher childhood IQ predicts a longer life on average, one of the sturdiest findings in cognitive epidemiology. But it is a population average, not a personal verdict, and most of the link runs through changeable factors.
IQ OutcomesIQ and Creativity
Intelligence and creativity are related but distinct, and an IQ test does not measure creativity. The famous threshold idea has mixed evidence, and openness, expertise, and drive matter as much as IQ above a baseline.
ArticlesLeft Brain vs Right Brain
The idea that you are a logical left-brained or creative right-brained person is a myth: a study of 1,000+ brains found no dominant hemisphere. But lateralization is real. Here is what your hemispheres actually do.
IQ OutcomesEmotional Intelligence vs IQ
Emotional intelligence is real but oversold. IQ is the better-validated predictor of learning and job performance, and most EQ tests measure personality. The honest EQ vs IQ comparison.
ArticlesTypes of Intelligence
The popular types of intelligence come from Gardner's multiple intelligences theory, loved in education but scientifically contested: the intelligences correlate, so the evidence points to a general factor (g) plus correlated CHC broad abilities.
IQ OutcomesIQ and Mental Health
The link between IQ and mental health is weak and complex. The popular claim that intelligent people suffer more is not what large studies show; they lean the other way, with bipolar disorder as the exception.
ArticlesThe Highest IQ Ever Recorded
There is no reliable highest IQ ever: validated tests cap around 160, and famous numbers like 228 or 300 are childhood ratio IQs, estimates, or non-standard scores. Guinness retired the record in 1990.
IQ OutcomesDyslexia and IQ
Dyslexia is a reading difficulty, not a thinking deficit. It is essentially uncorrelated with IQ, so dyslexic people span the full range, including gifted, and a single score can understate them.
ArticlesIQ Test Questions
See real IQ test questions across every type, verbal, quantitative, fluid-reasoning, spatial, memory, and speed, with worked examples. The honest catch: a few questions are not a test; only a full, normed battery gives a real score.
ArticlesSigns of High Intelligence
Some signs of high intelligence are backed by research and several are myths, but none can measure your IQ. Here is what the evidence supports, what it does not, and why only a real test can estimate ability.
Famous IQJeff Bezos's IQ: The Evidence and an Honest Estimate
Figures circulating for Bezos were picked to match his net worth. The checkable record is a National Merit scholarship and a summa cum laude Princeton degree.
Famous IQMarie Curie's IQ: The Evidence and an Honest Estimate
Curie was born in 1867, too late for the one historiometric study these figures come from. A defensible estimate is 170 to 190. See what her record shows.
Famous IQKanye West's IQ: The Evidence and an Honest Estimate
Kanye gave 133 in 2018 and other numbers since, none documented by an examiner. Weighing only the creative and business record gives roughly 115 to 130.
Famous IQLeBron James's IQ: The Evidence and an Honest Estimate
Teammates describe near photographic recall of games, which is trained expertise rather than a general score. A defensible band is 105 to 120.
Famous IQIsaac Newton's IQ: The Evidence and an Honest Estimate
Newton's 190 is not a measurement, and it is not printed in Catharine Cox's 1926 tables. A defensible range is 170 to 190.
Famous IQMark Zuckerberg's IQ: The Evidence and an Honest Estimate
The 152 appeared in coverage around 2010 and spread by repetition, never by measurement. The documented record points to 135 to 145. See what it rests on.
Famous IQSteve Jobs's IQ: The Evidence and an Honest Estimate
The 160 stretches a fourth grade achievement result, reported by Walter Isaacson, into a score no test produced. A defensible range is 125 to 140.
Famous IQBill Gates's IQ: The Evidence and an Honest Estimate
Gates scored 1590 on the pre-1995 SAT, but converting that into 160 skips a statistical correction. A defensible estimate is 140 to 150. See the working.
IQ OutcomesADHD and IQ
ADHD does not lower intelligence, but it can lower a measured IQ score through working memory and processing speed. People with ADHD span the full IQ range, including gifted.
Famous IQTaylor Swift's IQ: The Evidence and an Honest Estimate
Both 160 and 136 circulate for Swift, with no test, document or interview behind either. See how estimator pages manufacture figures like these.
IQ OutcomesAutism and IQ
Autism spans the entire IQ range, from intellectual disability to gifted, and standard verbal tests can underestimate autistic intelligence. See what the evidence shows.
IQ OutcomesWhat Is the Average IQ?
The average IQ is 100, and most people score 85 to 115. See what that means, how the scale works, and how the average shifts by age, country, and education.
Professional TestsWhere to Take an IQ Test: Your Options, In Person and Online
Where can you take an IQ test? A psychologist's office, a Mensa session, a university clinic, or online from home. See every option honestly and how to choose the right one for your reason.
Professional TestsPre-Employment Cognitive Test: What It Is and How to Know Your Real Score
Employers use cognitive tests like the Wonderlic and CCAT to predict job performance. See what they measure, what a good score is, whether you can prepare, and how to know your real cognitive ability.
Professional TestsHow Much Does an IQ Test Cost? The Honest Price Ladder
An IQ test costs from $0 to over $6,000. See the honest price ladder, what each tier buys, why prices vary so much, and how to get an accurate score without the clinical bill.
Professional TestsFull Scale IQ Test: What It Is and How to Take a Real One
A Full Scale IQ test combines many subtests across cognitive domains into one overall score, unlike single-task quizzes. See what it is, why breadth means accuracy, and how to take a real one.
Professional TestsCulture-Fair IQ Test: What It Is and How to Take One
A culture-fair IQ test uses abstract figures to measure fluid reasoning with less language and cultural bias. See how it works, why no test is truly culture-free, and how ACIS measures it.
Famous IQDonald Trump's IQ: The Evidence and an Honest Estimate
The 156 was inferred from Wharton admission and an assumed SAT, never a test. The only cognitive test on record is a dementia screen, which is not an IQ.
Professional TestsProfessional IQ Test: What It Really Means
What separates a professional IQ test from a casual quiz: real norms, documented reliability, and CFA validation. Compare the standards, then take one online free.
ArticlesMensa IQ Test: What It Takes & How to Estimate Yours
Mensa admits the top 2% (about IQ 130). ACIS isn't Mensa, but estimates if you're near the bar more precisely than the brief tests Mensa uses. Start free.
ArticlesCognitive Ability Test: Measure How Your Mind Works
Take a cognitive ability test online, the same construct as an IQ test. 20 subtests across six domains, real adult norms, and a detailed report. Start free.
Professional TestsFree IQ Test: Start Free, Real Test, Real Norms
Take a free IQ test online: start free and try real ACIS subtests at no cost. Your Full Scale IQ, six-domain profile, and detailed report unlock with a paid assessment.
Professional TestsIQ Test for Adults: Accurate, Adult-Normed, Online
Take a free, accurate online IQ test for adults aged 16-90. ACIS uses real adult norms, 20 subtests, and a detailed score report. Start free, then go deeper.
Professional TestsOnline IQ Test: Take a Real One, From Home
Take an online IQ test that's actually normed: 20 subtests, six domains, percentiles and a full report. See how to spot a real online IQ test and start free.
Professional TestsAccurate IQ Test: What Makes a Score Real
What makes an IQ test accurate? Reliability, validity, and real norms. See how to judge any test, how to get an accurate result, and try ACIS free.
ArticlesIQ Test With Detailed Results
Learn what an IQ test with detailed results should include, from FSIQ and domain scores to percentiles, confidence intervals, and profile interpretation.
ArticlesFluid vs. Crystallized Intelligence: What's the difference?
Fluid vs. crystallized intelligence explained: learn the difference between Gf and Gc, how IQ tests measure each ability, and how to interpret uneven cognitive profiles.
ArticlesWhat is a Full Scale IQ? How to understand it
What is a Full Scale IQ? Learn how to understand FSIQ, index scores, confidence intervals, percentiles, g, and score reports without overreading one number.
IQ OutcomesAverage IQ by Profession
Average IQ by profession guide: compare career IQ estimate ranges, job complexity, selection effects, and why profession averages do not define individuals.
IQ OutcomesIQ and Income: Correlation, Evidence, Limits
IQ and income research guide: correlations, meta-analytic evidence, education, SES, job complexity, earnings, and why IQ is not destiny.
IQ OutcomesIQ and Job Performance
See what meta-analyses say about IQ, general mental ability, job performance, training success, work complexity, selection, and limits.
IQ OutcomesIQ and Academic Achievement
See what meta-analyses say about IQ and academic achievement, including school grades, standardized tests, education, limits, and ACIS interpretation.
ArticlesCommon IQ Test Myths Debunked
Common IQ test myths debunked: learn what IQ measures, what it misses and how to interpret genetics, practice and online scores.
ArticlesIs IQ Genetic? Heritability Explained
Is IQ genetic? Learn what heritability means, how genes and environment interact, and why group or individual claims need caution.
Professional TestsWhat Is Raven's 2?
Learn what Raven's 2 is, who it is for, how paper and Q-global administration work, what scores it reports, and where this nonverbal professional battery fits.
Professional TestsHow Does the Stanford-Binet 5 Work?
Stanford-Binet 5 guide: learn age range, routing, factors, scores and why the SB5 remains important in professional assessment.
Professional TestsWAIS-5 vs Stanford-Binet 5
WAIS-5 vs Stanford-Binet 5: compare age range, structure, scores, routing and best-fit use cases using official source material.
Professional TestsWhat Is the WAIS-5?
WAIS-5 age range is 16:0 to 90:11. See its subtests, scores, timing and administration, plus how to measure the same broad cognitive abilities online with ACIS.
Professional TestsProfessional IQ Test vs Online IQ Test
Compare professional and online IQ tests by accuracy, supervision, norms, reliability, score use, reports, and limits.
Famous IQNikola Tesla IQ: Official Score or Estimate?
Tesla's 160 is repeated as fact across dozens of sites, none of which names a test or a date. See what Britannica documents and how the figure spread.
Famous IQAlbert Einstein IQ: Official Score or Estimate?
Britannica states plainly that Einstein's IQ is unknown and that no evidence shows he was ever tested. See where the 160 came from and what he did leave.
Famous IQLeonardo da Vinci IQ: Estimate or Speculation?
Leonardo died centuries before IQ testing existed, yet sites publish 180 and even 220 for him. See how those figures were assembled and what survives.
Famous IQElon Musk IQ: Is 155 Confirmed?
The viral 155 has no test, date or examiner behind it. Conversions from his reported SAT land closer to the low 120s. See what each number rests on.
Famous IQStephen Hawking IQ: Was It 160?
The 160 attached to Hawking is cultural shorthand, not a score report. See where it came from, what his Cambridge record documents, and what it is worth.
IQ OutcomesAverage IQ by Education Level
Average IQ by education level: search 2026 groups, sample sizes and trends with careful caveats about selection and interpretation.
IQ OutcomesAverage IQ by Country
Average IQ by country: search 2026 estimates, sample sizes and trends with strong caveats about culture, data quality and misuse.
Famous IQStandard Deviation 15 Explained
Learn what SD 15 means in IQ testing, how SD 15, SD 16, and SD 24 scales compare, and why percentiles matter more than raw IQ numbers.
ArticlesFree vs. Validated IQ Tests
Compare free online IQ tests, paid assessments, norms, reliability, score reports, and limits before trusting a quick result.
ArticlesAre Online IQ Tests Accurate?
Learn when an online IQ test can be accurate enough for personal insight, what signs to trust, and why many quick quizzes mislead.
IQ OutcomesAverage IQ by Age
Learn why the average IQ stays 100 at every age, how age norms work, and how fluid reasoning, memory, speed, and knowledge change across the lifespan.
ArticlesThe Importance of IQ
Why IQ matters: see how intelligence relates to learning, work and health outcomes, plus the limits of IQ when judging success.
ArticlesHistory of IQ Testing
History of IQ testing: follow Binet, Simon, Stern, Stanford-Binet and Wechsler from early scales to modern CHC assessment.
IQ OutcomesDoes IQ Predict Success?
The real correlations between IQ and income, job performance, and academic achievement, what they mean in practice, and where the evidence stops.
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