Learn about IQ & intelligence
Plain-English guides to IQ scores, scales, percentiles and what the research actually says — so you know exactly what your results mean.
Start with the IQ scale and score chart if you want the core framework — every range, level and classification rating — then use the IQ percentile calculator for exact score-by-score lookups.
Free toolIQ Percentile Calculator →Enter any IQ score and instantly see its percentile, rarity and classification.What Is the Average IQ? Average Intelligence and the Normal IQ Range
The average IQ score is 100 by definition. What counts as a normal IQ, what average intelligence means for adults, and why some sources put the average human IQ near 85 instead.
Read the guide →IQ Test for Kids: How Children Are Really Tested
How a real IQ test for kids works: the WISC-V, WPPSI-IV and Stanford-Binet, what age to test, what a child's score means, and why free online kids' IQ tests are not measurement.
Read the guide →What Is a High IQ? Where High and Good IQ Scores Begin
A high IQ is usually 130 or above — the top 2%. See what is considered a high IQ score, where a good IQ starts, and what 110, 120, 125 and 130 actually mean.
Read the guide →The IQ Scale and IQ Score Chart: All IQ Ranges, Levels and Ratings
The complete IQ score chart: every IQ range and level, its classification rating, the share of people in it and the matching percentile — plus how IQ scoring works and why published charts disagree.
Read the guide →IQ Test Questions: Sample Questions With Answers and Explanations
Sample IQ test questions with answers and worked explanations: matrix reasoning, pattern completion, number sequences, verbal analogies and spatial rotation, plus how to practice IQ test questions honestly.
Read the guide →Average IQ by Age: How Scores Are Adjusted Across a Lifetime
IQ is age-normed, so the average is 100 at every age — but raw cognitive abilities rise and fall across life. See how fluid and crystallized intelligence change by decade.
Read the guide →The Highest IQ Ever Recorded: Who Has the Highest IQ in the World?
Marilyn vos Savant’s 228 is the highest IQ ever recorded—but no modern test can produce it. What the highest possible IQ score really is, and which famous claims are verified.
Read the guide →Can You Increase Your IQ? How to Raise a Score, and by How Much
Can IQ be improved? Education adds roughly 1–5 points per extra year of schooling, while brain training mostly fails to transfer. What the evidence says about how to increase intelligence, and whether IQ changes over a lifetime.
Read the guide →How IQ Tests Work: What an IQ Test Measures and How IQ Is Calculated
What does an IQ test measure, and how is IQ calculated? The abilities each test samples, how a raw score is measured against a norming sample, and how deviation scoring turns it into a number.
Read the guide →Are IQ Tests Accurate? How Reliable IQ Scores Really Are
How accurate are IQ tests? A well-built test carries a margin of error of roughly ±5 to ±7 points. See what reliability, validity and IQ test accuracy actually mean.
Read the guide →Cognitive Ability Tests: Types, Uses and How to Prepare
Cognitive ability tests measure reasoning, memory and processing speed — used in hiring, education and self-assessment. Here's what they cover and how to prepare.
Read the guide →The 9 Enneagram Types Explained: Which One Are You?
A clear guide to the nine Enneagram personality types — core motivations, fears, strengths and growth paths — plus how the Enneagram compares to trait-based tests.
Read the guide →Type A vs Type B Personality: Traits, Myths and the Research
Driven and deadline-focused, or relaxed and flexible? What Type A and Type B actually mean, where the theory came from, and what modern research says.
Read the guide →How to Make a Career Change: A Practical, Evidence-Based Guide
Thinking about changing careers? A step-by-step framework: assess your interests and strengths, test-drive options, manage the finances and make the switch.
Read the guide →The Mensa IQ Test: Requirements, Minimum IQ and How to Join
Mensa's requirement is a supervised test score at the 98th percentile — a minimum IQ of about 130–132 on an SD-15 scale, 148 on Cattell. The admission test, the prior-evidence route and how to join.
Read the guide →EQ vs IQ: The Difference Between IQ and EQ, and Which Matters More
IQ measures reasoning ability; EQ describes how well you read and manage emotions. The differences between IQ and EQ, how each is measured, and why the two overlap far less than people assume.
Read the guide →Fluid and Crystallized Intelligence: Definitions, Examples and Differences
Fluid intelligence solves novel problems; crystallized intelligence applies accumulated knowledge. Clear definitions, concrete examples of each, how they differ and how they change with age.
Read the guide →Career Aptitude Tests: What They Measure and How to Use One
Career aptitude tests combine interests, strengths and working style to suggest fitting fields. What good tests measure, what to ignore, and how to act on results.
Read the guide →Personality Type Compatibility: How the 16 Types Get Along
Compatibility chart for all 16 personality types: easiest, complementary and hardest matches for every four-letter code — plus what type compatibility can and can't predict.
Read the guide →The Smartest Personality Type: What the Evidence Actually Shows
Which personality type has the highest IQ? No credible data ranks the 16 types by intelligence. Here's where the rankings come from, what research does show, and how to measure ability properly.
Read the guide →Is myiq.com Legit? An Honest Look at How It Works
Is myiq.com a scam or legit? How the myiq.com IQ test and subscription actually work, what its Trustpilot reviews show, how to cancel, and what to check before paying.
Read the guide →How to Cancel a myiq.com Subscription (Step by Step)
Every way to cancel a myiq.com subscription: in-account cancellation, email, and what to do about unexpected recurring charges — plus how to keep testing your IQ afterwards.
Read the guide →Is 16 Personalities Accurate? What Psychometrics Says
How accurate is the 16 personalities test? What type frameworks can and can't measure, what test-retest research shows, and how to get value from a type result anyway.
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