An average IQ score is 100, and about half of all people score between 90 and 109, the range most tests call Average. A score of 110 to 119 is above average, 120 or higher beats about 91 percent of people, and 130 or higher, reached by about 2 percent, is the usual threshold for "gifted" or Mensa-level scores. Whether a score is "good" depends on what you want it to tell you.
The IQ scale at a glance
Modern IQ tests are scaled so that the average for each age group is 100 and the standard deviation is 15. If scores follow a normal distribution, that fixes how many people land in each band. The table uses the bands from the Wechsler tests, the most widely used clinical IQ batteries in the United States.
| IQ score | WISC-V label | Older Wechsler label (e.g. WAIS-IV) | Share of people | Percentile rank |
|---|---|---|---|---|
| 130 and above | Extremely High | Very Superior | 2.5% | 98th and up |
| 120–129 | Very High | Superior | 7.2% | 91st–97th |
| 110–119 | High Average | High Average | 16.6% | 75th–90th |
| 90–109 | Average | Average | 49.5% | 25th–73rd |
| 80–89 | Low Average | Low Average | 15.6% | 9th–23rd |
| 70–79 | Very Low | Borderline | 6.5% | 2nd–8th |
| 69 and below | Extremely Low | Extremely Low | 2.1% | 2nd and below |
The shares are normal-distribution math for whole-number scores with a mean of 100 and a standard deviation of 15. They are slightly lopsided (16.6 percent above the Average band, 15.6 percent below) because the 90–109 band is centered on 99.5, not 100. Real samples follow this curve closely in the middle and less closely in the far tails.
The labels are the part that changes most. The WISC-V (2014) replaced "Superior" and "Borderline" with neutral terms like "Very High" and "Very Low," and other tests, including the Stanford-Binet Fifth Edition, use their own descriptors and cut points. No single label set is universal, so read the label in your report against that test's manual. For the percentile of any individual score from 55 to 145, use the IQ scale table.
What is a good IQ score?
There is no official "good" score, but a few reference points help:
- 100 is exactly average for your age group, by design. It is higher than half the population.
- 110 is higher than about 75 percent of people.
- 115, one standard deviation above the mean, is higher than about 84 percent.
- 120 is higher than about 91 percent, roughly 1 person in 11.
- 130, two standard deviations above the mean, is higher than about 98 percent, roughly 1 in 44.
If "good" means "enough to do well in school or most jobs," the honest answer is that the Average range already covers most of what people do, and the correlations between IQ and real outcomes are moderate. Effort, knowledge, health, and opportunity account for a great deal of the rest. A score of 105 versus 110 says very little about how a particular person will fare.
What is an average IQ score?
The average is 100 by definition, and most manuals treat 90 to 109 as the Average range. Because every score is relative to people of the same age, an average 8-year-old and an average 60-year-old both score 100 even though their raw answers look very different.
One complication is the age of the norms. Raw scores rose substantially during the 20th century, by 5 to 25 points in a single generation across the 14 nations Flynn (1987) examined, so a test normed long ago can make people look better than a freshly normed one would. That is one reason publishers re-norm their tests every 10 to 20 years.
High IQ score ranges
Above 130 the numbers thin out quickly. Under the normal curve, about 2.1 percent of people score from 130 to 144, and about 0.13 percent, roughly 1 in 740, score 145 or higher. A score of 160 is expected in about 1 person in 30,000.
Those far-tail figures are theoretical. The standard norms of major batteries such as the WISC-V stop at 160 (extended norms used in gifted assessment go higher, with even less precision), and even below that ceiling there are few people in the norming samples at the extremes, so very high scores are measured with less precision than scores near the middle. Gifted programs often use 130 as a guide, but criteria vary by state and school district, and many combine test scores with achievement, grades, and teacher input. Mensa admits people who score at or above the 98th percentile on an accepted test. For more on what the top of the scale means, see what counts as a genius IQ.
Low IQ score ranges
About 2 percent of people score below 70, two standard deviations under the mean. A low score on its own is not a diagnosis. Under the DSM-5-TR (2022), intellectual disability (intellectual developmental disorder) requires significant limits in both intellectual functioning and adaptive functioning (everyday conceptual, social, and practical skills), beginning during development. The manual describes the intellectual criterion as a score roughly two standard deviations below the mean, about 65 to 75 once measurement error is allowed for, and it sets severity levels by adaptive functioning rather than by IQ alone (American Psychiatric Association, 2013).
Scores in the 70s, labeled Very Low or Borderline depending on the test, often signal that a person may benefit from support at school or work, not that something is "wrong." Any decision about diagnosis, services, or educational placement belongs with a qualified clinician who has seen the full picture. This article is not medical or educational advice.
Are IQ ranges different for children and adults?
The bands are the same at every age, because every score is calculated against people of the same age. A 9-year-old with an IQ of 115 and a 45-year-old with an IQ of 115 are both higher than about 84 percent of their age peers, even though the adult answers far more questions correctly.
What differs is stability. Scores from early childhood, especially before school age, change more from one testing to the next than scores from adolescence and adulthood. That is why psychologists are cautious about labeling a young child from a single test, and why gifted and special-education decisions are usually reviewed over time. Adults also retain their rank fairly well, but a score of 108 at age 30 and 113 at age 40 is an ordinary amount of variation, not a sign that anything changed.
Why the same number can mean different things
Three things make IQ numbers harder to compare than they look:
- Different standard deviations. Almost all current clinical tests use 15, but older editions of the Stanford-Binet used 16, and tests reported on the Cattell scale use 24. A 148 on a scale with a standard deviation of 24 is the same percentile as 130 on a scale with 15.
- Different norm groups. A score only means something relative to the people the test was normed on. Clinical tests use large samples matched to the census; many online tests compare you only with whoever happened to take them.
- Measurement error. A full-scale IQ from a good clinical test has a 95 percent confidence interval often about 8 to 12 points wide. Two people scoring 108 and 112 may not differ in their true ability at all.
Our own test does not solve the second problem; it is open about it. Your result there is an estimated IQ — your percentile among the people who have taken the same form, converted to this scale — always shown with a range (plus or minus 12 percentile points on the short form, 7 on the full form) and labelled as an estimate, because the test has not been normed on a representative sample. The details are in how to interpret your IQ results, and the math linking scores to percentiles is in how IQ scores are calculated.
How score ranges are built
Publishers give the test to a large norming sample, often a few thousand people stratified by age, sex, region, education, and ethnicity to match census data. Raw scores in each age group are converted to scaled scores so that the group's mean becomes 100 and its standard deviation 15. Your score then shows where you would fall among those people. The shape of that conversion, and the reason so many people cluster near 100, is covered in the IQ bell curve explained.