Methodology
How we turn answers into a number
We'd rather over-explain than over-promise. Here is the full, unglamorous truth about how the score works — and where it doesn't.
What an IQ score actually is
Modern IQ is a relative measure. Your raw answers mean nothing on their own; what matters is how you compare to everyone else. Standardised tests are scaled so the average is 100 and the standard deviation is 15. That single fact explains the whole scale:
- • about 68% of people score between 85 and 115;
- • about 95% score between 70 and 130;
- • roughly the top 2% score 130 or above.
Our scoring, step by step
- 1. Weighted score. Each of the 30 questions has a difficulty weight (1 = easy, 2 = medium, 3 = hard). We add up the weights of the questions you answered correctly and divide by the maximum possible — giving a performance ratio from 0 to 1.
- 2. Map to the curve. That ratio is converted into a standard score using a calibration where a typical timed performance lands near 100, a near-perfect run approaches the gifted range, and weaker performances fall below the midpoint.
- 3. Deviation IQ. The result is expressed as
IQ = 100 + 15 × z, clamped to a sensible display range (55–145), and your percentile is read straight off the normal distribution.
Example: a score of 122 sits well into the upper tail.
Why “culture-fair” matters
Our visual sections — the matrices and spatial puzzles — are designed in the tradition of Raven's Progressive Matrices. They rely on pattern and rule-finding rather than vocabulary or schooling, so they travel across languages and backgrounds and get closer to fluid intelligence: your raw reasoning power.
The honest limits
This is a free screening test for curiosity and self-insight, not a clinical instrument. A real diagnostic IQ assessment (like the WAIS) is administered one-to-one by a trained psychologist and normed on thousands of people. We can't replicate that in a browser, and we won't pretend to. Treat your result as a fun, reasonably informative estimate with a genuine margin of error — never as a medical or psychological diagnosis, and never as a measure of your worth.