About IQQuiz

What IQQuiz is

IQQuiz is a free collection of IQ-style reasoning quizzes and IQ score reference tools. Every quiz runs entirely in your browser, shows your practice result instantly, and explains every answer. Every score tool interprets an existing standardized score on the common mean-100, SD-15 reference scale. No email, no account, and no payment is requested anywhere on the site.

How the content is made

All quiz questions are written in-house and human-checked one by one: each item has exactly one defensible answer, and every explanation shows the rule or calculation that proves it. Figure puzzles are drawn from deterministic parameters — rotation, scale, fill, dot counts — so the answers are provable rather than guessed. The score tools share one mathematical engine (the standard normal cumulative distribution), and its outputs are locked to known anchors: IQ 85 ≈ 15.87th percentile, IQ 100 = 50th, IQ 115 ≈ 84.13th, IQ 130 ≈ 97.72nd, with ±1σ covering 68.27% and ±2σ covering 95.45% of the reference distribution.

Editorial rules

1. Practice results are practice results. They are never converted into standardized IQ numbers, percentiles, or classifications.
2. The site claims no clinical validity, no Mensa affiliation, and no diagnostic or hiring use.
3. Score tools only interpret scores obtained from real standardized assessments, and they say so on every page.
4. Statistics are computed, not eyeballed, and verified by automated checks before release.
5. Sources for the reference scale and testing standards are cited on every page.