IQ Score Guide: Every Score from 55 to 160 Explained
Complete reference for every IQ score: percentile rank, Wechsler classification, and rarity. Based on the standard Wechsler scale (M = 100, SD = 15). 3 scores currently have detailed guides.
How to use this guide
Every IQ score corresponds to a specific percentile rank and classification. The grid below covers the complete range from 55 to 160 — so whatever score you're looking up, you'll find where it sits in the population. Scores with a detailed article available are shown with an arrow — click through for a full breakdown.
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Take our 50-question assessmentHow IQ scores work
Modern IQ tests are standardised so the population mean is 100 and the standard deviation is 15. That convention is called the Wechsler scale, after the Wechsler Adult Intelligence Scale (WAIS) — the gold-standard clinical test used worldwide since 1939.
The scale produces a normal distribution — the familiar bell curve. About 68% score between 85 and 115; about 95% score between 70 and 130; only about 2% score above 130 or below 70.
IQ scores also carry measurement error. Any observed score is an estimate within roughly ±5 points of your true underlying ability. See how accurate is an IQ score? for a full explanation.
Classification bands
The Wechsler classification system groups scores into seven bands. These labels are used in clinical IQ reports worldwide.
| Range | Classification | Percentile |
|---|---|---|
| IQ 130 and above | Very Superior | Top 2% |
| IQ 120 - 129 | Superior | 91st - 98th percentile |
| IQ 110 - 119 | High Average | 75th - 90th percentile |
| IQ 90 - 109 | Average | 25th - 75th percentile |
| IQ 80 - 89 | Low Average | 9th - 25th percentile |
| IQ 70 - 79 | Borderline | 2nd - 9th percentile |
| IQ 55 - 69 | Extremely Low | Bottom 2% |
Every score at a glance
Every IQ score from 55 to 160, grouped by classification band. Each tile shows the score and its percentile. Scores with a detailed article are clickable — look for the arrow indicator.
Very Superior
IQ 130 and above · Top 2%
Superior
IQ 120 - 129 · 91st - 98th percentile
High Average
IQ 110 - 119 · 75th - 90th percentile
Average
IQ 90 - 109 · 25th - 75th percentile
Low Average
IQ 80 - 89 · 9th - 25th percentile
Borderline
IQ 70 - 79 · 2nd - 9th percentile
Extremely Low
IQ 55 - 69 · Bottom 2%
Percentiles calculated from the standard normal cumulative distribution function using Wechsler scale parameters (M = 100, SD = 15). Values under 10 or over 90 are shown to one decimal place; all others are rounded to the nearest whole number.
How to read the grid
- Percentile is non-linear. Going from IQ 100 to 110 covers 25 percentile points. Going from 140 to 150 covers less than half a percentile point. The curve flattens at the tails.
- Different scales give different numbers. This grid uses the Wechsler scale (SD = 15). Stanford-Binet L-M (SD = 16) gives 132 instead of 130 for the Mensa threshold. Cattell III B (SD = 24) gives 148.
- Clinical reports include confidence intervals. A professional report for an observed 118 will say “FSIQ 118 (95% CI: 113-123).” That range is where your true ability probably is.
Related reading
Find your place on the grid
Our 50-question assessment covers verbal, numerical, spatial, and memory reasoning — the same four domains measured by clinical tests like the WAIS. You get your score, your exact percentile, and a breakdown of where you're strongest.
Take the test50 questions · Full cognitive breakdown · 2.5M+ completed
Sources
- Wechsler, D. (2008). Wechsler Adult Intelligence Scale–Fourth Edition (WAIS-IV) Technical and Interpretive Manual. San Antonio, TX: Pearson.
- Abramowitz, M., & Stegun, I. A. (1964). Handbook of Mathematical Functions (formula 7.1.26, used for the error-function approximation).
- Kaufman, A. S. (2009). IQ Testing 101. New York: Springer Publishing.