IQ Scores & Percentile Chart: Normal Distribution & Meaning
Understand how IQ scores translate to population percentiles along the Gaussian bell curve. Compare Wechsler, Stanford-Binet, and Mensa qualification thresholds.
Standard Normal Distribution of IQ Scores
Standardized cognitive assessments use a Gaussian normal distribution with a mean score ($\mu$) of 100 and a standard deviation ($\sigma$) of 15 points. Because test scores follow a bell curve, raw points directly correspond to exact population percentile ranks.
| IQ Score (SD 15) | Percentile Rank | Classification | Rarity in Population |
|---|---|---|---|
| 145+ | 99.9th Percentile | Exceptionally Gifted | 1 in 741 people |
| 135 – 144 | 99.0th – 99.8th Percentile | Highly Gifted | 1 in 100 people |
| 130 – 134 | 98th Percentile (Mensa Cutoff) | Superior / Gifted | 1 in 50 people |
| 125 – 129 | 95th – 97th Percentile | Very High Average | 1 in 20 people |
| 120 – 124 | 91st – 94th Percentile | High Average | 1 in 11 people |
| 110 – 119 | 75th – 90th Percentile | High Average | 1 in 4 people |
| 90 – 109 | 25th – 74th Percentile | Average (Median Range) | 1 in 2 people (50%) |
| 80 – 89 | 9th – 24th Percentile | Low Average | 1 in 6 people |
| 70 – 79 | 2nd – 8th Percentile | Borderline | 1 in 16 people |
125 IQ Percentile: What Does a 125 IQ Score Mean?
An IQ score of 125 places an individual at approximately the 95.2 percentile. This means that someone with a 125 IQ performs higher than roughly 95 out of every 100 individuals in the normative population. Individuals at this level demonstrate strong abstract pattern recognition, rapid verbal comprehension, and advanced deductive reasoning capabilities.
What Percentile is a 130 IQ Score?
An IQ of 130 is positioned at the 97.7 percentile (two standard deviations above the population mean of 100). A score of 130 serves as the primary threshold for high-IQ societies like Mensa, which requires evidence of a score in the top 2% of the general population.
Is 135 a Good IQ Score?
Yes. An IQ of 135 places an individual in the 99th percentile, signifying intellectual performance that surpasses 99% of the population. This range is formally classified as "Highly Gifted" on modern scales such as the Wechsler Adult Intelligence Scale (WAIS-IV) and Stanford-Binet (SB5).
Is an IQ of 110 Good? What Does 110 to 117 Mean?
An IQ score between 110 and 117 falls into the High Average tier:
- IQ 110: Placed at the 75th percentile, higher than 75% of the normative group.
- IQ 117: Placed at the 87th percentile, reflecting above-average working memory, fluid reasoning, and verbal comprehension.
Frequently Asked Questions About IQ Scores & Percentiles
What percentile is a 125 IQ?
A 125 IQ corresponds to approximately the 95th percentile on the Wechsler and Stanford-Binet scales (using standard deviation 15). It ranks higher than approximately 95.2% of the general population.
Is 135 a good IQ score?
An IQ score of 135 is classified as Highly Gifted and falls in the 99th percentile of the population.
What percentile is a 130 IQ?
A 130 IQ corresponds to the 98th percentile (top 2% of the population) and meets the qualification cutoff for Mensa.
Is an IQ of 110 a good score?
An IQ of 110 is classified as High Average and ranks in the 75th percentile of the general population.
How does IQ Checker XYZ relate to these percentiles?
IQ Checker XYZ scales public communication writing style against standard bell curve distributions for educational analysis. It is not an assessment of biological or clinical intelligence.