How we score the IQ test
39 puzzles, each one right or wrong. The number you get right goes through a fixed norm table and comes out as an IQ and a percentile.
The puzzles
Every puzzle is a matrix: a grid of shapes that follow a rule, with one piece missing. You pick the piece that completes the grid. There are 39 of them, and they get harder as you go.
Each puzzle is scored right or wrong. There is no partial credit and no bonus for a hard puzzle. Your raw score is simply how many you got right.
From right answers to an IQ
Your raw score goes through a fixed norm table. Each number of right answers has one IQ next to it, so the same raw score always gives the same IQ, for everyone, every time.
The IQ is on the usual IQ scale, where the average is 100 and the standard deviation is 15 (Neisser et al., 1996). About two thirds of people score between 85 and 115.
At the two ends, the table stops: a result under 79 is shown as below 79, and a result over 145 as above 145. Past those points the table can't tell scores apart, so you get the range, not a made-up number.
We don't publish the norm table or the answers. If they were public, the test would stop measuring anything for the next person who takes it.
What a percentile is
Your percentile is the share of people you scored higher than. An IQ of 115 is the 84th percentile: higher than 84 of every 100 people. It comes straight from the IQ scale's bell curve, so the percentile on your result and on your certificate is always the same number.
Percentiles run from 1st to 99th. Any IQ, worked out both ways, is in the IQ percentile calculator.
IQ and percentile
| IQ | Percentile | Higher than |
|---|---|---|
| 70 | 2nd | 2 of 100 people |
| 75 | 5th | 5 of 100 people |
| 80 | 9th | 9 of 100 people |
| 85 | 16th | 16 of 100 people |
| 90 | 25th | 25 of 100 people |
| 95 | 37th | 37 of 100 people |
| 100 | 50th | 50 of 100 people |
| 105 | 63rd | 63 of 100 people |
| 110 | 75th | 75 of 100 people |
| 115 | 84th | 84 of 100 people |
| 120 | 91st | 91 of 100 people |
| 125 | 95th | 95 of 100 people |
| 130 | 98th | 98 of 100 people |
| 135 | 99th | 99 of 100 people |
| 140 | 99th | 99 of 100 people |
| 145 | 99th | 99 of 100 people |
What each range means and how common it is: the IQ scale.
Retests
In the app you can take the IQ test again. The next test opens 14 days after your last one, once you have played 10 training games in the last 14 days. The next test is never the one you just took, so you don't see the same puzzles twice in a row.
Your IQ only ever comes from an IQ test. The training games don't change it.