IQ Percentile Chart: What Your Score Really Means Next to Everyone Else

You get your IQ result and the number is 118. Is that good? Rare? Average with a nice haircut? On its own, the number does not tell you much. Next to everyone else, it suddenly does: 118 means you scored higher than roughly 88 out of every 100 people your age.

That translation, from score to percentile, is the most useful way to understand any IQ result. Below you will find a full IQ percentile chart, how to read it, why the same number can sit at different percentiles on different tests, and what a percentile can never tell you.

What an IQ percentile actually means

A percentile tells you the share of people in a comparison group who scored below you. If you are at the 75th percentile, you outscored about 75% of that group.

It is not the same as a percentage of questions answered correctly. You could get 60% of items right and land at the 90th percentile if the test is hard, or get 80% right and land near the middle if it is easy.

Most modern IQ tests are scaled so that the average is 100 and one standard deviation is 15 points. Because scores follow a bell-shaped normal distribution, every score maps neatly onto a percentile. If you want the full background on the curve, our guide to what a good IQ score is explains it step by step.

The IQ percentile chart

This chart uses the standard scale (mean 100, standard deviation 15). Percentiles are rounded and based on the theoretical normal curve, which real test data follow closely in the middle and less precisely at the extremes.

How to read the chart

The middle is wide and crowded

Around 68% of people score between 85 and 115, and about half score between 90 and 110. That means a big jump in percentile can come from just a few points near the middle. Going from 100 to 110 moves you from the 50th to the 75th percentile.

The tails are thin and stretched out

At the top end, each extra point changes the percentile only slightly but makes the score much rarer. Going from 130 to 140 only moves you from the 97.7th to the 99.6th percentile, yet you go from about 1 in 44 people to about 1 in 260.

Small gaps are often noise

Every test has measurement error, typically a few points either way. Professional reports often present a confidence interval, such as 112 to 120, rather than one number. A 108 and a 112 are best read as overlapping, not as meaningfully different.

Why the same score can mean different percentiles

Not every test uses the same scale, and percentiles depend on the comparison group.

• Different standard deviations. Most modern tests use 15, but older Stanford-Binet editions used 16 and the Cattell scale uses 24. On the Cattell scale, a score of 148 sits at roughly the same percentile as 130 on a Wechsler test. This is why high-IQ societies set the bar as a percentile, as explained in our post on the Mensa IQ requirement.
• Age norms. IQ scores compare you with people your age. A 100 at age 20 and a 100 at age 70 reflect very different raw performance, but the same relative position.
• Old or new norms. Because average performance shifted over the 20th century, a test with outdated norms can give inflated scores. That is one reason tests are re-normed every so often.

Why extreme scores are less certain

The further you move from the average, the less precise any score becomes. Norm samples, even large ones, include very few people at the extremes, so the exact percentile for a score of 150 is estimated from the curve rather than observed directly. Many tests also have a ceiling: once you answer nearly everything correctly, they cannot distinguish between very high scorers.

That is why claims of extraordinary IQs, such as 180 or 200, deserve a raised eyebrow. On a standard scale, those scores would be so rare that no test could reliably measure them, a problem we unpack in the highest IQ ever recorded.

Common labels for score ranges

Test publishers use slightly different words, but a typical set of descriptions looks like this:

1. 130 and above: very high, roughly the top 2%.
2. 120 to 129: high, roughly the 91st to 97th percentile.
3. 110 to 119: high average, roughly the 75th to 90th percentile.
4. 90 to 109: average, the broad middle half of people.
5. 80 to 89: low average, roughly the 9th to 24th percentile.
6. Below 80: lower ranges, where a professional assessment gives a far fuller picture than any single score.

Labels are descriptive shorthand, not verdicts. The percentile carries the real information.

What a percentile can't tell you

A percentile places your performance on one test, on one day, relative to people your age. It does not measure creativity, emotional skill, persistence, curiosity or wisdom, and it does not set a ceiling on what you can learn. Plenty of people at every point on the chart lead rich, successful lives.

If you would like to see your own position, you can take our free IQ test, which reports both an estimated score and the percentile that goes with it.

The bottom line

An IQ percentile turns an abstract number into something meaningful: the share of people your age you outscored. On the standard scale, 100 is the 50th percentile, 115 is about the 84th and 130 is about the 98th. Read small differences as noise, be sceptical of extreme claims, and remember that the chart describes one test result, not the whole of you.

FAQ

What percentile is an IQ of 120?

An IQ of 120 is around the 91st percentile on a standard scale, meaning you scored higher than about 91% of people your age. Roughly one person in eleven scores at or above that level.

What IQ is in the top 1%?

On a scale with a standard deviation of 15, the top 1% starts at roughly 135. On scales with a larger standard deviation, the equivalent number is higher.

Is percentile the same as percentage correct?

No. Percentage correct is how many questions you got right, while percentile compares your performance with other people. A hard test can give a high percentile with a modest percentage correct.