The science

What an IQ score actually tells you.

Home of IQ is built on established psychometric ideas, with the limits of online testing stated up front. Here's the bell curve, the four domains, and how our 35 questions land you on it.

Step 1

Your score is a place on a curve.

IQ is a standardized score: mean 100, standard deviation 15. About 68% of people fall between 85 and 115, and about 95% fall between 70 and 130. The number itself doesn't mean much in isolation — what matters is the band you sit in and the gap between your domains.

Hover a band to see where most people land, and where the tails are.

mean 1007085100115130

Step 2

Four domains, four broad abilities.

We follow the Cattell-Horn-Carroll (CHC) tradition: general intelligence is composed of broad abilities, not one number. Our four rooms map directly to four of the best-evidenced broad abilities.

Logical reasoning

CHC: Fluid reasoning (Gf)

Solving problems you have not seen before by finding the rule that connects them. Pattern recognition, deduction, and abstract sequencing.

Item types

Matrix-style patterns inspired by Raven's Progressive Matrices, odd-one-out, syllogistic reasoning, and rule-finding sequences.

Where it shows up in life

Reading a new spreadsheet, debugging an unfamiliar process, planning three moves ahead.

Step 3

How our test is built.

The mechanics behind the 35 questions — nothing fancy, nothing hidden.

35 items, four domains, growing difficulty

Items are spread across logical, numerical, verbal, and spatial reasoning, interleaved in roughly increasing difficulty bands. Every domain contributes to your overall score and gets its own sub-score.

Calibrated against population norms

Raw scores are mapped to the standard IQ scale (mean 100, standard deviation 15), the same convention Wechsler tests use. Your percentile reflects where you fall on that distribution.

Item-band difficulty, not adaptive in v1

We use fixed difficulty bands instead of adaptive item selection so the experience is identical for everyone, and so the score is fully reproducible. Item-response calibration runs in the background on anonymous, aggregated answers.

What this test is not

Honest about the limits.

  • Not a clinical assessment. For diagnostic or legal purposes, see a licensed psychologist.
  • Not proctored. Online conditions vary — expect a confidence band, not a precise number.
  • Not a measure of worth. IQ is a narrow construct — it ignores creativity, drive, and emotional intelligence.
  • Not used to gate anyone. Your data is yours; we never sell scores or share them with employers.

Deep dive

The questions everyone asks.

Find your place on the curve.

35 questions. About 10 minutes. The science up front and the results easy to act on.

Start the IQ test