IQ 128: what it means, percentile and how rare it is
An IQ score of 128 is higher than about 96.9% of people, which puts it in the 97th percentile. Roughly 1 in 32 people score higher than 128. On the WISC-V it is classified as Very High.
- Percentile
- 97th
- Higher than
- 96.9%
- People scoring higher
- 1 in 32
- WISC-V classification
- Very High
What does an IQ of 128 mean?
- Mensa admits people who score in the top 2% on an approved, supervised test, which is 130 on the Wechsler scales. 128 is 2 points below that line.
- In a group of 100 people, about 3 would score higher than 128.
Scores from 120 to 129 are Very High on the WISC-V (Superior on the WAIS-IV and the Stanford-Binet 5). About 7% of people score in this range, roughly the top 9% to 3% of the population.
People with scores here usually learn quickly, cope well with abstract and unfamiliar problems and do well in academically demanding settings. It is a strong result on any professionally administered test.
Scores near the top of this range sit just under the 130 line used by many gifted programmes and by Mensa. With a measurement margin of about ±5 points, a result of 126 to 129 on one test can be 130 or above on another.
IQ 128 on other scales and tests
Different tests spread scores differently. The same rank as an IQ of 128 on an SD-15 test gives these numbers elsewhere:
| Scale | Equivalent score | Classification |
|---|---|---|
| SD 15: WISC-V, WAIS, Stanford-Binet 5 | 128 | Very High |
| WAIS-IV (older label) | 128 | Superior |
| Stanford-Binet 5 | 128 | Superior |
| SD 16: older Stanford-Binet, Cattell Culture Fair | 130 | – |
| SD 24: Cattell III B | 145 | – |
How precise is an IQ score of 128?
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 128 is best read as "probably somewhere between 123 and 133". 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 128
| IQ score | Percentile | Higher than | WISC-V classification |
|---|---|---|---|
| 123 | 94th | 93.7% | Very High |
| 124 | 95th | 94.5% | Very High |
| 125 | 95th | 95.2% | Very High |
| 126 | 96th | 95.8% | Very High |
| 127 | 96th | 96.4% | Very High |
| 128 | 97th | 96.9% | Very High |
| 129 | 97th | 97.3% | Very High |
| 130 | 98th | 97.7% | Extremely High |
| 131 | 98th | 98.1% | Extremely High |
| 132 | 98th | 98.4% | Extremely High |
| 133 | 99th | 98.6% | Extremely High |
Check another IQ score
For example 98 for the top 2%.
- Percentile
- 97th
- Higher than
- 96.9%
- People scoring higher
- 1 in 32
- Classification (WISC-V)
- Very High
IQ 128: frequently asked questions
Is an IQ of 128 good?+
Yes. An IQ of 128 is well above the average of 100 and higher than about 96.9% of people. Tests classify it as Very High.
What percentile is an IQ of 128?+
An IQ of 128 is in the 97th percentile on a scale with mean 100 and standard deviation 15. It is higher than about 96.9% of people and lower than about 3.1%.
How rare is an IQ of 128?+
Roughly 1 in 32 people score higher than 128. In a group of 1,000 people you would expect about 31 to score higher.
Does an IQ of 128 qualify for Mensa?+
Not on its own. Mensa admits people who score in the top 2% on an approved, supervised test, which is 130 on the Wechsler scales. 128 is 2 points below that line, though scores can vary by a few points between tests.