Understanding IQ

An IQ score is easy to get and easy to misread. These guides explain what the number actually represents, how it is calculated, what it predicts, and — just as importantly — what it does not.

What Is IQ? A Plain-Language Explanation

Where the number comes from, why the average is 100, and what psychologists mean by general intelligence.

8 min read

IQ Score Ranges and What Each One Means

From below 70 to above 130 — the percentile behind each band, and how rare each score really is.

7 min read

What Is the Average IQ, and Why Is It Always 100?

100 is a design decision, not a discovery. How norming works and what the Flynn effect did to it.

7 min read

How IQ Tests Work: Question Types and Scoring

Matrix reasoning, number series, spatial rotation — what each question type probes and how raw answers become a score.

9 min read

Online IQ Tests vs. Professional Assessment

What an online test can honestly tell you, and where a supervised WAIS assessment is the only real answer.

8 min read

Can You Improve Your IQ Score? What the Evidence Says

Brain training, practice effects, sleep — separating what moves a score from what only appears to.

8 min read

Frequently Asked Questions About IQ Testing

Short answers to the questions people ask most about scores, percentiles and retaking a test.

6 min read

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