Everything about IQ, explained honestly
In-depth guides on what IQ scores actually mean, how tests work, what the research supports, and where the popular myths go wrong.
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IQ Score Guide: every score from 55 to 160
Percentile, classification, and rarity for every IQ score — plus detailed guides for specific scores. Start here to find what your score means.
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Can You Improve Your IQ? What the Research Actually Says
Yes, but modestly. Formal education adds 1-5 IQ points per year (Ritchie & Tucker-Drob, 2018). Exercise and sleep help. Brain-training apps mostly don't. Here's what the research supports and what it doesn't - with realistic expectations about timeframes.
How to Join Mensa: Qualifying Scores, Accepted Tests, and the Process
Mensa requires a score at the 98th percentile or above - IQ 130 on Wechsler, 132 on older Stanford-Binet. Here's the complete guide to qualifying tests, the process in the US and UK, fees, preparation, and what membership actually offers.
How Accurate Is an IQ Score? What Measurement Error Actually Means
Professional IQ tests have reliability of 0.95+ but every score has a ±5 point margin. Here's how to read your score with the confidence interval applied, why scores change between tests, and how online tests compare.
IQ vs EQ: What's the Actual Difference?
IQ measures cognitive ability; EQ measures emotional and social skill. They correlate only weakly - here's what each one actually predicts, and which matters more for what.
Average IQ by Country, Age, and Profession: What the Data Actually Says
A careful look at average IQ across countries, age groups, and professions - including which of these comparisons are methodologically sound and which are internet folklore.
How Accurate Are Online IQ Tests?
Well-designed online IQ tests estimate your score within about 10-15 points of a clinical assessment. Badly designed ones are essentially random. Here's how to tell the difference.
What Is a Good IQ Score? A Complete Breakdown by Percentile
A good IQ score is typically 110 or above - putting you in the top 25% of the population. Here's the full percentile breakdown, what each IQ range means, and where you rank.
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