The IQ scale: ranges, levels and percentiles
IQ scores are set so that 100 is the average and every 15 points is one standard deviation. About 68% of people score between 85 and 115, about 95% between 70 and 130, and about 2% score 130 or more.
Each shaded band is one level in Table 1. The curve is the normal distribution with a mean of 100 and a standard deviation of 15, the scale most IQ tests use. The middle band, 90 to 109, holds about 49% of people.
IQ chart: ranges, levels and percentiles
| IQ range | Level | Percentile | Share of people |
|---|---|---|---|
| 130 and above | Very high | 97.5 and above | 2% |
| 120 to 129 | High | 90.3 to 97.5 | 7% |
| 110 to 119 | High average | 73.6 to 90.3 | 17% |
| 90 to 109 | Average | 24.1 to 73.6 | 49% |
| 80 to 89 | Low average | 8.5 to 24.1 | 16% |
| 70 to 79 | Below average | 2.1 to 8.5 | 6% |
| Below 70 | Well below average | Below 2.1 | 2% |
Level names are our own plain ones. Test publishers use their own labels, and they differ from test to test. Percentiles and shares come from the bell curve, counting whole scores (a range of 110 to 119 covers 109.5 to 119.5 on the curve).
| IQ | Percentile | How rare | Level |
|---|---|---|---|
| 55 | 0.13 | 1 in 741 score this or lower | Well below average |
| 60 | 0.38 | 1 in 261 score this or lower | Well below average |
| 65 | 0.98 | 1 in 102 score this or lower | Well below average |
| 70 | 2.2 | 1 in 44 score this or lower | Below average |
| 75 | 4.7 | 1 in 21 score this or lower | Below average |
| 80 | 9.1 | 1 in 11 score this or lower | Low average |
| 85 | 15.8 | 1 in 6 score this or lower | Low average |
| 90 | 25.2 | 1 in 4 score this or lower | Average |
| 95 | 36.9 | 1 in 3 score this or lower | Average |
| 100 | 50.0 | Half score higher | Average |
| 105 | 63.0 | 1 in 3 score this or higher | Average |
| 110 | 74.7 | 1 in 4 score this or higher | High average |
| 115 | 84.1 | 1 in 6 score this or higher | High average |
| 120 | 90.8 | 1 in 11 score this or higher | High |
| 125 | 95.2 | 1 in 21 score this or higher | High |
| 130 | 97.7 | 1 in 44 score this or higher | Very high |
| 135 | 99.01 | 1 in 102 score this or higher | Very high |
| 140 | 99.61 | 1 in 261 score this or higher | Very high |
| 145 | 99.86 | 1 in 741 score this or higher | Very high |
| 150 | 99.957 | 1 in 2,300 score this or higher | Very high |
| 155 | 99.987 | 1 in 8,100 score this or higher | Very high |
| 160 | 99.996 | 1 in 32,000 score this or higher | Very high |
The percentile is the share of people who score lower. Each score links to a page about it.
Every score from 70 to 160
Pick a score to see its percentile, how rare it is and what it means.
Very high
What is a good IQ score?
Any score from 90 to 109 is average, and about half of all people land there. A score of 110 or more is above average: higher than about 74% of people. A score of 120 or more is higher than about 90%.
Whether a score is good depends on what you want it for. For a test taken out of interest, any score in or above the average range is a normal, healthy result.
What is a high IQ?
A score of 130 or above is usually counted as high. It is higher than about 97.7% of people, and about 1 in 44 people score that or more.
Mensa, the high-IQ society, admits people who score in the top 2% on an approved test. On a scale with a standard deviation of 15 that is about 131 or more.1
What IQ is considered genius?
There is no scientific cut-off for genius, and modern tests do not use the word. The idea comes from Lewis Terman, who in 1916 labelled scores above 140 "near genius or genius" on his early version of the Stanford-Binet test.
On today's scale a score of 140 is higher than about 99.61% of people, about 1 in 261. It describes how rare a test score is, not what a person can create or achieve.2
What is a low IQ?
Scores from 80 to 89 are low average and scores from 70 to 79 are below average. About 2.2% of people score below 70.
A low score on one test, especially a short one taken online, is not a diagnosis of anything. A tired or rushed sitting can pull a score down. If a score matters for school, work or health, a psychologist can give a full assessment in person.
How high can IQ go?
There is no fixed top to the scale, but tests stop measuring precisely long before any limit. A score of 160 is four standard deviations above the average, which the curve puts at about 1 in 32,000 people.
Even a large norm group has very few people that far from the middle, so a test has little to compare a score of 160 or more against. Most tests report their highest scores as a range or stop at a ceiling. Ours stops at 145.
Why do some tests use 15, 16 or 24 points?
Tests agree that 100 is the average, but not on the size of one standard deviation. Most modern tests use 15. Older editions of the Stanford-Binet used 16, and the Cattell scale uses 24.
So the same rarity gets a different number. Mensa's top-2% line is a score of 132 on the Stanford-Binet and 148 on the Cattell scale. Two standard deviations above the average is 130 on a 15-point scale, 132 on a 16-point scale and 148 on a 24-point scale.1
What one score cannot tell you
Every test score is an estimate. A retake would rarely give the same number, so a score should be read with its margin of error: on our test about 9 points either side.
A score describes how someone did on one set of reasoning tasks on one day. It does not measure what a person knows, how hard they work or what they will achieve.3
Related pages
Sources
- Mensa International. What is IQ? (read 13 November 2026). www.mensa.org/what-is-iq/
- Terman, L. M. (1916). The Measurement of Intelligence. Boston: Houghton Mifflin, p. 79. archive.org/details/measurementofint00term
- American Educational Research Association, American Psychological Association and National Council on Measurement in Education (2014). Standards for Educational and Psychological Testing, chapter 2: Reliability/Precision and Errors of Measurement. www.testingstandards.net/open-access-files.html
First published 13 November 2026.