IQ and reasoning
What is a good IQ test score?
4 min read
The short answer: IQ scores are set so that the average is 100. About two people in three score between 85 and 115, so anything in that range is typical. Scores from 115 to 130 are above average, and scores above 130 are reached by only about 2 people in 100.
But "good" depends on what you want the number for. Here is what the scores mean, and what they leave out.
How IQ scores work
An IQ score is not a count of right answers. It compares your result with the results of a large group of people of the same age who took the same test. Scores are arranged so that:
- the average is 100;
- the spread around it is set so that 15 points is one standard step (a "standard deviation").
Because most abilities are spread in a bell-shaped curve, this gives a predictable picture:
- About 68% of people score between 85 and 115.
- About 95% score between 70 and 130.
- About 2% score above 130, and about 2% below 70.
So a score of 115 means you did better than roughly 84 people out of 100. A score of 130 means better than about 98 out of 100.
What counts as low, average or high
Different tests use slightly different labels, but they broadly agree:
- Below 70: well below average. On professionally given tests, this is one of several things looked at, together with everyday functioning, before any diagnosis is considered.
- 70 to 84: below the average range.
- 85 to 114: the average range, where most people are.
- 115 to 129: above average.
- 130 and above: well above average. This is the level many "high IQ" societies ask for (Mensa, for example, accepts people in the top 2% of a recognized test).
A single point rarely matters. Every test has a margin of error, usually several points either way, so 112 and 117 may not be truly different. That is why good tests give a likely range as well as a number.
Why scores from different tests differ
- Different norms. A score only means something compared with a reference group. A test compared with a very selective group will give lower scores than one compared with the general population.
- The Flynn effect. Average scores on IQ tests rose by roughly 3 points per decade through much of the 20th century, so tests are re-normed from time to time. An old test can make people look better than a recently normed one.
- Online tests. Most online IQ tests, including ours, have not been normed on a large, representative group. Their scores are estimates, not official IQ scores. They can give you a useful idea of how you reason, but they are not a substitute for a test given by a psychologist.
- Your day. Tiredness, stress, time pressure, and how familiar you are with this kind of puzzle all move scores up or down.
What an IQ score can and cannot tell you
IQ tests measure a particular set of skills: spotting patterns, reasoning with numbers and words, holding information in mind, and working things out under some time pressure. Research shows these scores are linked, on average, with how people do at school and, more loosely, at work.
They say nothing direct about:
- creativity and imagination;
- practical sense and judgment;
- knowledge and experience in a field;
- how well you understand and get on with people;
- motivation, persistence and character.
Many of the things that make a life go well depend on those. A high score is not a guarantee, and an average score is not a limit.
So, what is a good score?
For most purposes, any score in or above the average range (85 and up) is a perfectly good score: it means your reasoning works like most people's or better. If you are curious about where you stand, the most useful way to read a score is as a rough picture of how you solve new problems today, not as a fixed label.
Try it yourself
The Happy Me Reasoning – IQ Test has 30 pattern, number and word puzzles in 20 minutes, and gives you an estimated score on the IQ scale with its likely range. It is free, and you do not need an account. It is an estimate, not an official IQ score.
Sources
- Neisser, U., et al. (1996). Intelligence: Knowns and unknowns. American Psychologist, 51(2), 77–101.
- Deary, I. J. (2020). Intelligence: A Very Short Introduction (2nd ed.). Oxford University Press.
- Flynn, J. R. (1987). Massive IQ gains in 14 nations: What IQ tests really measure. Psychological Bulletin, 101(2), 171–191.
- Schmidt, F. L., & Hunter, J. E. (1998). The validity and utility of selection methods in personnel psychology. Psychological Bulletin, 124(2), 262–274.