Guide
IQ classification, band by band
The WAIS-IV sorts IQ scores into seven labeled bands, from Extremely Low to Very Superior. The labels are useful shorthand for a range on the curve, as long as you remember what they are: names for stretches of a continuous scale, drawn at round numbers, around scores that each carry a few points of error.
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The seven bands at a glance
The table lists the WAIS-IV classification labels (Wikipedia: IQ classification), the scores each covers, and the share of people expected in each band on a normal curve with mean 100 and standard deviation 15. The shares are computed, not surveyed.
| Label | Scores | Share of people | Example |
|---|---|---|---|
| Very Superior | 130 and above | 2.5% | IQ 135 |
| Superior | 120 to 129 | 7.2% | IQ 124 |
| High Average | 110 to 119 | 16.6% | IQ 114 |
| Average | 90 to 109 | 49.5% | IQ 100 |
| Low Average | 80 to 89 | 15.6% | IQ 85 |
| Borderline | 70 to 79 | 6.5% | IQ 75 |
| Extremely Low | 69 and below | 2.1% | IQ 65 |
The bands are not equal in width. The Average band spans twenty points, the four bands either side of it span ten each, and the two outer bands are open-ended. Because most people sit near the middle of the curve, the Average band alone holds about half of everyone.
Where the scale comes from
Modern IQ tests report a deviation IQ: scores are standardized to a mean of 100 and a standard deviation of 15 within each age group (Wikipedia: Intelligence quotient). Every label is therefore a statement about rank among people your age. About 68% of people score between 85 and 115, about 95% between 70 and 130, and about 99.7% between 55 and 145 (the 68-95-99.7 rule). The label boundaries sit at round numbers on that scale, mostly at multiples of ten.
Try one · Logical Reasoning
Which tile completes the second pair?
Tap the option you think is right, or show the answer.
Show the answer
The missing panel shows a small outlined arrow pointing right on its own (option 3).
How to solve it
- Compare the first two panels and name exactly what changed.
- The whole figure turns a quarter turn clockwise.
- The large shape becomes outlined.
- Nothing else changes.
- Apply the same changes to the third panel: a small hatched arrow pointing up on its own.
- So the missing panel shows a small outlined arrow pointing right on its own.
That was 1 puzzle. The full test has 25.
Band by band
Very Superior: 130 and above
The highest label on the WAIS-IV scale, for scores two or more standard deviations above the mean. An IQ of 130 is higher than about 97.7% of people. Mensa's line, the 98th percentile on an approved, supervised test (Mensa International), falls just above 130 on this scale. See what an IQ of 135 means or what IQ is the top 2%.
Superior: 120 to 129
Clearly above average: between about one and a third and two standard deviations above the mean. About 7.2% of people score in this band. A score of 120 is higher than about 90.9% of people; 129 is higher than about 97.3%. See IQ 124.
High Average: 110 to 119
The upper edge of the typical range, a little under one standard deviation above the mean or just past it. About 16.6% of people land here. By the one-standard-deviation convention, scores up to 115 are still inside the typical range, so a score of 112 can be described as both High Average and typical. See IQ 114.
Average: 90 to 109
The middle of the scale, centered on the mean of 100. This is the single largest band. It holds about 49.5% of people. A score of 90 and a score of 109 differ by nineteen points but share the same label, which is a good reminder that labels are coarse. See IQ 100 and what is the average IQ.
Low Average: 80 to 89
The lower edge of the typical range, below the average band but within about one and a third standard deviations of the mean. About 15.6% of people score here. A score of 85 sits exactly one standard deviation below the mean, the lower edge of the 85 to 115 typical range. See IQ 85.
Borderline: 70 to 79
Between about one and a third and two standard deviations below the mean. About 6.5% of people score in this band. The word “borderline” names a score range on a test, not a description of a person. See IQ 75.
Extremely Low: 69 and below
More than two standard deviations below the mean, the lowest label on the WAIS-IV scale. About 2.1% of people score here on the normal curve. A low score on any single test is not a diagnosis; a licensed psychologist uses a full standardized assessment and much more information before drawing conclusions. See IQ 65.
Same rank, different numbers
These labels assume a standard deviation of 15. Older Stanford-Binet forms used 16, and the Cattell Culture Fair III scale uses 24 (Wikipedia: IQ classification). The same rank that reads 130 on a standard test reads about 132 on an SD 16 test and 148 on an SD 24 test. Before you apply a label to a number, check which scale it came from. The percentile to IQ converter handles all three.
Why labels are only shorthand
Every measured score carries error. Clinical manuals report a confidence interval, often around plus or minus 5 points at 95% (Wechsler, 2008). A measured 119 and a measured 120 sit in different bands, High Average and Superior, yet their confidence intervals overlap almost completely. The honest reading of a score near a boundary is that it sits near a boundary.
Labels also describe test performance, not a whole person. Two people with the same label can differ widely in what they know, how they work and what they care about. For a fuller way to read a result, see how to read an IQ score, and for the curve behind all of this, read the IQ bell curve, explained.
How IQ Octopus uses the labels
IQ Octopus reports an estimated IQ on the standard deviation 15 scale, with a confidence range, and shows the matching WAIS-IV label. It is not a clinical or diagnostic instrument, and its label is a description of the estimate, nothing more. To see every score from 55 to 160 with its label and percentile, open the IQ score chart.
Sources
- IQ classification. Wikipedia. en.wikipedia.org/wiki/IQ_classification
- Intelligence quotient. Wikipedia. en.wikipedia.org/wiki/Intelligence_quotient
- 68-95-99.7 rule. Wikipedia. en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule
- Wechsler, D. (2008). WAIS-IV Technical and Interpretive Manual. Pearson.
- About us. Mensa International. www.mensa.org/mensa/about-us