What does an IQ of 75 mean?
Below the central range on the reference scale, at approximately percentile 4.78.
- IQ score
- 75
- Percentile
- 4.78
- At or above
- 95.22%
Normal reference · mean 100 · SD 15. These are calculated values, not observed starp population ranks.
Where 75 sits on the IQ scale
A score of 75 is 25 points below the mean. Dividing by the standard deviation gives (75 − 100) ÷ 15 = -1.67. The normal cumulative distribution converts that standardized position into percentile 4.78.
This is below the central 85–115 interval of the reference scale. A single result does not provide a diagnosis or determine what someone can learn. The original report, testing conditions and purpose matter when interpreting it.
How common is a score of 75?
Approximately 4.78% of this model lies at or below 75—about 1 in 21. This is a cumulative share, not the chance of scoring exactly 75. A continuous model does not assign a positive probability to one exact value.
Compared with IQ 85, the reference percentile is 11.09 percentage points lower. Equal IQ-point gaps do not create equal percentile gaps: the middle of the bell curve contains more area than its ends.
Compare nearby scores
Compare 70 and 75 or calculate 75 on another scale. A small difference between test results is not automatically a meaningful change.
How this relates to starp
starp's current scoring map does not produce exactly 75. Its neighboring results are 73 for 16 correct answers and 77 for 17 correct answers out of 30. This guide explains the conventional scale value 75; it does not invent an intermediate starp result.
See the scoring method and how raw scores differ from IQ estimates.
Questions about IQ 75
Is 75 a good IQ score?
75 is below the reference mean of 100. It should be interpreted in the context of the test, rather than as a verdict on a person's abilities or future.
What percentile is an IQ of 75?
On a normal scale with mean 100 and standard deviation 15, 75 corresponds to approximately percentile 4.78. Around 95.22% of that model lies at or above it. Use an assessment's own norms for an actual reported rank.
Does an IQ of 75 mean 75% correct?
No. IQ is a scaled score. Percentage correct depends on the questions and scoring rules; percentile describes a relative position. These three quantities are not interchangeable.
Method: NIST's normal-distribution formula. Percentiles here are calculated reference values, not observed starp population ranks. About starp scoring.