IQ Score Chart: Ranges, Percentiles and Classifications
A full IQ score chart from 55 to 160 with percentiles, plus a converter between IQ and percentile.
This chart shows how IQ scores map to percentiles on the standard scale used by modern intelligence tests, where the average is 100 and the standard deviation is 15. Percentiles are calculated from the normal distribution; real populations deviate slightly, especially in the tails. If you want to understand what a score means in practice, read what is a good IQ score? alongside this page.
IQ to percentile table
| IQ score | Percentile (share scoring lower) | How rare at or above |
|---|---|---|
| 55 | about 0.1% | — |
| 60 | about 0.4% | — |
| 65 | about 1.0% | — |
| 70 | about 2% | — |
| 75 | about 5% | — |
| 80 | about 9% | — |
| 85 | about 16% | — |
| 90 | about 25% | — |
| 95 | about 37% | — |
| 100 | about 50% | — |
| 105 | about 63% | 1 in 3 |
| 110 | about 75% | 1 in 4 |
| 115 | about 84% | 1 in 6 |
| 120 | about 91% | 1 in 11 |
| 125 | about 95% | 1 in 21 |
| 130 | about 98% | 1 in 44 |
| 135 | about 99.0% | 1 in 102 |
| 140 | about 99.6% | 1 in 261 |
| 145 | about 99.9% | 1 in 741 |
| 150 | about 99.9+% | 1 in 2,331 |
| 160 | about 99.9+% | 1 in 31,574 |
"Percentile" is the share of the reference population expected to score below that value. An IQ of 130 has a percentile of about 98, meaning about 98% of people score lower and about 2% score the same or higher.
IQ to percentile converter
Classification bands
| IQ range | Descriptive label (Wechsler-style) |
|---|---|
| 130 and above | Very superior |
| 120–129 | Superior |
| 110–119 | High average |
| 90–109 | Average |
| 80–89 | Low average |
| 70–79 | Borderline |
| 69 and below | Extremely low |
Labels vary between test publishers and have changed over time. They describe performance relative to a reference group, not a person's worth or potential.
Notes on reading the chart
- Scale matters. Most current tests use a standard deviation of 15. Some older tests (for example early Stanford-Binet editions) used 16, and some high-IQ society tests use 24. The same raw ability gives different numbers on different scales, so always check the standard deviation.
- Error range. Each score has a confidence interval. A score of 120 on a professional test is typically reported as roughly 115–125.
- The tails are thin. Above about 145 there are few people in any norming sample, so scores there are estimates, not precise measurements.
- Re-norming. Scores drift over time (the Flynn effect), so tests are re-standardised periodically.
How our test relates to this chart
The CoreSkillAI IQ test places its guessing-corrected score on this same scale using a stated statistical assumption, not a norm table from a representative sample. Its results are capped at 135 and shown with a 95% confidence interval of about ±11 points. The scale is useful for comparison with the chart, but the result is an estimate. Read are online IQ tests accurate? and our methodology for the details.
Frequently asked questions
What is the average IQ?
100, by definition. Tests are scaled so that the average person in the reference group scores 100.
What IQ is considered genius?
There is no scientific cut-off for "genius". The word describes exceptional creative or intellectual achievement, which IQ does not capture. In testing, scores of 130 and above are usually called very superior or gifted-range, about the top 2%.
What percentage of people have an IQ above 130?
About 2%, on the standard scale with a standard deviation of 15. Above 145 it is about 1 in 750, and above 160 about 1 in 31,000, but scores that high cannot be measured precisely.
Is an IQ of 120 good?
It is in the superior range, higher than about 91% of the reference group. Whether it is "good" depends on what you want to do with it; see our guide.
Can IQ change?
Scores are fairly stable in adulthood but vary by a few points from day to day and test to test, and they are less stable in childhood. Education, health, sleep and practice effects all play a part.
Why does the chart not go above 160?
Few people score that high, and tests cannot distinguish reliably between very high scores. Claims of IQs of 180 or 200 on informal tests are not meaningful.
Sources
- Wechsler, D. (2008). WAIS-IV Technical and Interpretive Manual. Pearson. (scale and classifications)
- Roid, G. H. (2003). Stanford-Binet Intelligence Scales, Fifth Edition. Riverside Publishing.
- The percentile values on this page are computed from the normal distribution with mean 100 and standard deviation 15.