The IQ scale explained
IQ scores are set so the average is 100. Here is what each range means, how common it is, and how to read your own result.
Updated 2026-09-30
An IQ score compares your reasoning with other people’s. Most modern tests use the same scale: the average is 100, and scores spread out around it with a standard deviation of 15 points. That means about two in three people score between 85 and 115.
The IQ scale follows a bell curve. Most people score near the middle.
IQ score ranges
Test publishers use slightly different labels, but these bands are widely used. The share of people in each band follows from the bell curve.
| IQ score | Common label | Share of people |
|---|---|---|
| 130 and above | Very superior | about 2% |
| 120–129 | Superior | about 7% |
| 110–119 | High average | about 16% |
| 90–109 | Average | about 50% |
| 80–89 | Low average | about 16% |
| 70–79 | Borderline | about 7% |
| Below 70 | Extremely low | about 2% |
IQ percentiles
A percentile tells you the share of people you scored higher than. On a scale with a mean of 100 and a standard deviation of 15:
| IQ score | Percentile | Higher than about |
|---|---|---|
| 70 | 2nd | 2% of people |
| 85 | 16th | 16% of people |
| 100 | 50th | 50% of people |
| 110 | 75th | 75% of people |
| 115 | 84th | 84% of people |
| 120 | 91st | 91% of people |
| 130 | 98th | 98% of people |
| 145 | 99.9th | 99.9% of people |
Why the average stays at 100
IQ is a relative score, not a count of correct answers. When a test is published, it is taken by a large sample of people and scored so their average is 100. Over the 20th century, average raw scores rose in many countries by roughly 3 points per decade, known as the Flynn effect. Tests are renormed from time to time so that 100 keeps meaning average.
How to read your result
- Look at the range, not a single number. Any test has measurement error. A result of 112 is best read as “somewhere around 105 to 119”.
- Online tests are estimates. A formal IQ assessment is given one-to-one by a psychologist and takes over an hour. Ours, like other online tests, gives a useful estimate for self-reflection, not a diagnosis.
- Scores can move. Tiredness, stress and familiarity with the puzzle types can shift results by several points.
Want to know how our test is built and scored? Read how our tests work.
Common questions
What is the average IQ?
The average IQ is 100 by definition. Modern IQ tests are scored against a large sample of people so that the average lands at 100, with a standard deviation of 15 points.
What is a good IQ score?
Any score from 90 to 109 is average. Scores from 110 to 119 are high average, 120 to 129 are superior, and 130 or above puts you in roughly the top 2% of people.
What percentile is an IQ of 120?
An IQ of 120 is about the 91st percentile, meaning it is higher than roughly 91% of people on a scale with a mean of 100 and a standard deviation of 15.
Can your IQ change?
Scores are fairly stable in adulthood but not fixed. Results can move several points between sittings because of sleep, stress, practice with similar puzzles and the specific test used.
Try it yourself
Take the free IQ test