What does an IQ of 80 mean?
Below the central range on the reference scale, at approximately percentile 9.12.
- IQ score
- 80
- Percentile
- 9.12
- At or above
- 90.88%
Normal reference · mean 100 · SD 15. These are calculated values, not observed starp population ranks.
Where 80 sits on the IQ scale
A score of 80 is 20 points below the mean. Dividing by the standard deviation gives (80 − 100) ÷ 15 = -1.33. The normal cumulative distribution converts that standardized position into percentile 9.12.
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 80?
Approximately 9.12% of this model lies at or below 80—about 1 in 11. This is a cumulative share, not the chance of scoring exactly 80. A continuous model does not assign a positive probability to one exact value.
Compared with IQ 85, the reference percentile is 6.74 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 75 and 80 or calculate 80 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 80. Its neighboring results are 77 for 17 correct answers and 81 for 18 correct answers out of 30. This guide explains the conventional scale value 80; it does not invent an intermediate starp result.
See the scoring method and how raw scores differ from IQ estimates.
Questions about IQ 80
Is 80 a good IQ score?
80 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 80?
On a normal scale with mean 100 and standard deviation 15, 80 corresponds to approximately percentile 9.12. Around 90.88% of that model lies at or above it. Use an assessment's own norms for an actual reported rank.
Does an IQ of 80 mean 80% 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.