What are the IQ score ranges?

On the common 15-point scale, the typical bands are: 130 and above (very high), 120–129 (superior), 110–119 (above average), 90–109 (average), 80–89 (below average), and below 80 (well below average). Labels vary slightly between publishers.

What does an IQ of 100 mean?

An IQ of 100 is exactly average — the 50th percentile. It means you scored higher than about half of people in your age group, because tests are scaled so the population mean is 100.

Are the IQ classification labels official?

No. The band names are conventions, and different test publishers word them differently. The underlying percentiles are consistent, but the labels attached to ranges are descriptive, not fixed scientific categories.

Why does the scale depend on the standard deviation?

The same label can sit at a different number depending on the test's standard deviation. Most tests use 15, but some (such as the Cattell scale) use 16, which shifts where a band like "top 2%" falls. Always check the percentile, not just the number.

The IQ Scale Explained: What Every Score Range Means

The IQ scale runs from well below 70 to above 130, centred on an average of 100. Each stretch of the scale carries a familiar label — average, above average, superior, very high — but those labels are conventions, not hard boundaries. Here is what each range actually means, and why the same word can sit at a different number on different tests.

How the scale is built

IQ scores are scaled so the population average is 100, with a standard deviation of 15 on most modern tests. That single design choice fixes the whole scale: each 15-point step is one standard deviation away from the average, and the percentage of people in each band follows directly from the bell curve. We cover that distribution in the IQ bell curve, and the average itself in what the average IQ is.

The classification bands

The bands below are typical and match the classification we show on our results. Read them as descriptive ranges, not scientific cut-offs — a 109 and a 110 are not meaningfully different people:

130 and above — very high; roughly the top 2% of scores.
120–129 — superior; around the top 10%.
110–119 — above average.
90–109 — average, where most people fall.
80–89 — below average.
70–79 — well below average.
Below 70 — used in formal assessment only as one part of a much broader clinical evaluation, never from an online test.

The top end of the scale is covered in more detail in what is a high IQ, and the meaning of "good" across the whole range in what a good IQ score means.

Percentiles tell you more than the label

A percentile is the share of people you scored higher than, and it is often clearer than the raw number. An IQ of 100 is the 50th percentile; 115 is about the 84th; 130 is around the 98th. Because percentiles do not depend on which scale a test uses, they let you compare results across tests fairly — which is exactly why high-IQ societies define entry by percentile, as we explain in what IQ you need for Mensa.

Why the same label can sit at a different number

Watch the standard deviation. Most tests use SD 15, but some (such as the Cattell scale) use 16 or another value, which moves where each band lands. "Top 2%" is about 130 on an SD-15 test but about 132 on an SD-16 test, and other figures you may see — like 148 — come from scales with a larger spread. The classification labels stay the same; the numbers attached to them do not. Always anchor on the percentile.

Reading your own score

Where you land on the scale is a useful snapshot, but no single number is a fixed verdict — scores carry a margin of error and shift with conditions, especially on unsupervised tests (see how accurate online IQ tests are). If you would like to see roughly where you sit, our age-normed free IQ test places your result on exactly this scale.