IQ Percentile Calculator
Enter an IQ score to see exactly where it falls in the population: the percentile, how rare the score is, and its position on the bell curve. The math uses the standard scoring model behind every major modern IQ test: a normal distribution with a mean of 100 and a standard deviation of 15.
Percentile
91st
Rarity
1 in 11
Classification
Superior
High
See the full breakdown for this score on our Is 120 IQ good? page, or compare against the complete IQ percentile chart.
How the Calculation Works
IQ is a standardized score. When a test is developed, it is given to a large normative sample, and raw performance is mapped onto a scale where the average is 100 and one standard deviation is 15 points. That design choice means percentiles follow directly from the normal curve: a score of 115 is one standard deviation above the mean, which works out to about the 84th percentile, while 130 is two standard deviations up, around the 98th. This calculator applies the exact cumulative normal distribution rather than a lookup table, so every score from 40 to 200 gets a mathematically precise percentile and rarity figure.
Rarity is the same number viewed from the other direction. If a score sits at the 98th percentile, then roughly 1 person in 50 scores at that level or higher. Rarity grows explosively in the tails: moving from 130 to 145 takes you from 1 in 44 to roughly 1 in 741, and 160 is beyond 1 in 31,000. This is why claimed celebrity scores above 180 deserve skepticism: at that level there are only a few thousand people on Earth, and almost none of them have verified test results.
What Percentiles Mean in Practice
Percentiles are most useful for understanding relative standing, not for predicting any individual outcome. Research summarized in our guide to IQ in the workplace shows general cognitive ability is among the strongest single predictors of job performance, yet the correlation still leaves most of the variation unexplained. A 91st-percentile score opens no doors by itself, and a 40th-percentile score closes none. If you have not measured your score recently, our free 30-question IQ test gives an instant estimate you can bring back to this calculator.
Frequently Asked Questions
How is an IQ percentile calculated?
IQ tests are normed so scores follow a normal distribution with a mean of 100 and a standard deviation of 15. Your percentile is the share of the population scoring below you on that curve. An IQ of 100 is the 50th percentile, 115 is roughly the 84th, and 130 is roughly the 98th.
What percentile is an IQ of 120?
An IQ of 120 sits at about the 91st percentile, meaning a score higher than roughly 9 out of 10 people. It falls in the superior range on most classification systems.
Is a higher percentile always better?
A higher percentile means rarer performance on the test, but IQ measures a specific set of reasoning abilities, not worth or potential. Conscientiousness, creativity, and social skill all predict life outcomes independently of IQ.
Why do different tests give slightly different percentiles?
Tests are normed on different samples in different years, and some use a standard deviation of 16 instead of 15. The same underlying performance can therefore land a point or two apart across tests. Treat percentiles as close estimates rather than exact figures.
More Free IQ Tools
- How Rare Is Your IQ?: shareable rarity card for any score
- SAT, ACT and GRE to IQ Converter: estimate IQ from test scores
- Celebrity IQ Match: see which famous figures share your score
MyIQScores Editorial Team
Researchers in cognitive psychology, psychometrics & educational science
Last updated
May 10, 2026
All content on MyIQScores is reviewed for scientific accuracy against peer-reviewed research in cognitive psychology and psychometrics. Our editorial team cross-references each article with published literature before publication and updates pages whenever new research warrants a revision.