IQ 99: what it means, percentile and how rare it is
An IQ score of 99 is higher than about 47.3% of people, which puts it in the 47th percentile. Roughly 1 in 2.1 people score lower than 99. On the WISC-V it is classified as Average.
- Percentile
- 47th
- Higher than
- 47.3%
- People scoring lower
- 1 in 2.1
- WISC-V classification
- Average
What does an IQ of 99 mean?
- In a group of 100 people, about 47 would score lower than 99.
About half of all people score between 90 and 109, the Average range. 100 is the exact middle of the scale by design: tests are normed so that the average adult or child of a given age scores 100.
Within this range, differences of a few points mean very little. Once measurement error of about ±5 points is taken into account, a 96 and a 104 are effectively the same result.
An average score is not a limit. Most people in every career and walk of life score in or near this range, and knowledge, skills, effort and personality explain far more about day-to-day success than a few IQ points.
IQ 99 on other scales and tests
Different tests spread scores differently. The same rank as an IQ of 99 on an SD-15 test gives these numbers elsewhere:
| Scale | Equivalent score | Classification |
|---|---|---|
| SD 15: WISC-V, WAIS, Stanford-Binet 5 | 99 | Average |
| WAIS-IV (older label) | 99 | Average |
| Stanford-Binet 5 | 99 | Average |
| SD 16: older Stanford-Binet, Cattell Culture Fair | 99 | – |
| SD 24: Cattell III B | 98 | – |
How precise is an IQ score of 99?
No test measures IQ exactly. On individually administered tests such as the WAIS, the full-scale score comes with a 95% confidence interval of roughly ±5 points, so a result of 99 is best read as "probably somewhere between 94 and 104". Scores can also shift a few points between different tests or after a few years.
Online tests, including ours, are self-assessments. They are useful for curiosity and practice, but they are not a substitute for an assessment by a psychologist.
IQ scores near 99
Check another IQ score
For example 98 for the top 2%.
- Percentile
- 47th
- Higher than
- 47.3%
- People scoring lower
- 1 in 2.1
- Classification (WISC-V)
- Average
IQ 99: frequently asked questions
Is an IQ of 99 good?+
An IQ of 99 is an average score: it is in the range where half of all people fall and it is higher than about 47.3% of people. It is a typical result, and it does not limit what you can learn or do.
What percentile is an IQ of 99?+
An IQ of 99 is in the 47th percentile on a scale with mean 100 and standard deviation 15. It is higher than about 47.3% of people and lower than about 52.7%.
How rare is an IQ of 99?+
Roughly 1 in 2.1 people score lower than 99. In a group of 1,000 people you would expect about 473 to score lower.
Is 99 above average?+
No, it is a little below the mean of 100, but it is still inside the Average range (90 to 109). The difference is smaller than the typical ±5-point measurement error, so in practice it is an average score.