— IQ score explained
IQ of 89 — meaning, percentile & profile
An IQ of 89 is in the low-average range, below 77% of adults. This does not predict life outcomes — context, motivation, and skills matter enormously.
What does IQ 89 mean in practice?
An IQ of 89 means your raw performance on a standardised IQ test places you at the 23th percentile of the general adult population — lower than 77% of people. Many people at this level succeed across a wide variety of careers and life domains with the right conditions and strategies.
IQ 89 and the normal distribution
IQ is defined with a mean of 100 and a standard deviation of 15. An IQ of 89 is 0.73 standard deviations below the mean. The normal distribution tells us that:
- About 68% of people score between 85 and 115
- About 95% of people score between 70 and 130
- About 99.7% of people score between 55 and 145
- An IQ of 89 is higher than 23% of the adult population
IQ 89 and career outcomes
Career success depends on far more than IQ — motivation, perseverance, social skills, practical reasoning, and domain knowledge are all equally or more important than the IQ number for most real-world outcomes. Many people with IQs in this range lead highly successful and fulfilling careers.
Comparing IQ 89 to common benchmarks
| Score | Percentile | Classification |
|---|---|---|
| IQ 75 | 5th | Borderline range |
| IQ 80 | 9th | Low average |
| IQ 85 | 16th | Low average |
| IQ 88 | 21th | Low average |
| IQ 90 | 25th | Average range |
How to accurately measure your IQ
A reliable IQ test uses Item Response Theory (IRT) scoring, which adapts the scoring based on item difficulty parameters rather than simply counting correct answers. Core Brain uses IRT 3PL (three-parameter logistic) scoring — the same statistical framework used by the WAIS and Stanford-Binet — and returns your score with a 95% confidence interval so you know the measurement uncertainty.
Related IQ scores
- IQ 75 — Borderline range, 5th percentile
- IQ 80 — Low average, 9th percentile
- IQ 85 — Low average, 16th percentile
- IQ 88 — Low average, 21th percentile
- IQ 90 — Average range, 25th percentile