On the reference scale, 140 sits in the very high range, around the 99.6th percentile. Here is what that means, and what it does not.
Prepared by IQInsight · Calculation guide · Updated
140 is far into the upper tail, but below three standard deviations.
A score of 140 is 40 points above the reference mean, or about 2.67 standard deviations. The upper tail is approximately 0.38%, around one value in 261. Three standard deviations above the mean would be 145, not 140.
The reference percentile changes from about 99.62 at 140 to 99.87 at 145. The small numerical gap in percentile does not make these scores interchangeable. Near a test’s upper limit, interpretation also requires evidence that the instrument can distinguish performance at that level.
How the percentile is calculated.
The reference uses a mean of 100 and a standard deviation of 15. First convert the score to a z-score, then find the area below it on the standard normal curve.
Theoretical normal distribution. Mean 100, standard deviation 15. This does not measure your IQ or compare you with IQInsight users.
Put the number in perspective.
In a normal distribution with mean 100 and standard deviation 15, about 0.38% of scores fall at or above 140. That is approximately one in 261. The figure describes the reference model; it is not a count of people we have tested.
The quality of the test matters.
A number alone does not show how accurately it was measured. An established, professionally administered test has supporting evidence and defined interpretation rules. An online exercise without representative norms cannot establish the same conclusions.
Nearby scores on the same scale.
Theoretical percentiles, mean 100 and standard deviation 15
Looking at the answers can be useful even when a score is only provisional. Which patterns did you notice? Which constraints did you overlook? Those are concrete things you can review without treating a single number as your identity.
Can a short online test reliably distinguish 140 from 145?+
The numbers alone cannot establish that. Evidence about the test’s precision, upper range and norms would be needed. IQInsight has not established those properties, so its high-end estimates should not be treated as precise measurements.
Is 140 a good IQ score?+
On a theoretical scale with mean 100 and standard deviation 15, 140 is in the very high range, around the 99.6th percentile. Whether a particular test result supports that interpretation depends on the quality and standardization of that test.
How rare is an IQ of 140?+
Under that normal-distribution model, about 0.38% of values are at or above 140, approximately 1 in 261. This is a mathematical reference, not observed IQInsight user data.
Does this number describe all of my abilities?+
No. IQ scores do not describe every skill, interest, quality or circumstance. A score on an unstandardized online exercise is especially limited and should not be treated as a diagnosis or a prediction of personal success.
Can I compare scores from different tests?+
Only with care. Tests can differ in norms, scales, questions, administration and reliability. Similar-looking numbers are not necessarily equivalent measurements.
Can I get my result without paying?+
Yes. IQInsight is designed to provide the estimated score, theoretical percentile and all four domain breakdowns for free. The optional report explains the answers in more detail.
