Average IQ by age chart
IQ is not a raw score. Every IQ test compares you with people your own age, so the average is 100 for every age group and about two thirds of people in each group score between 85 and 115.
| Age | Average IQ | Typical range (68%) | What changes in raw ability |
|---|---|---|---|
| 6–9 | 100 | 85–115 | Raw scores rise fast every year; reading and number skills drive much of the gain |
| 10–12 | 100 | 85–115 | Abstract reasoning develops; working memory keeps growing |
| 13–15 | 100 | 85–115 | Processing speed and fluid reasoning close to adult levels |
| 16–19 | 100 | 85–115 | Fluid reasoning near its peak |
| 20–29 | 100 | 85–115 | Peak for speed and new-problem solving |
| 30–44 | 100 | 85–115 | Speed eases slightly; vocabulary and knowledge keep growing |
| 45–64 | 100 | 85–115 | Knowledge and vocabulary peak; fast reasoning declines slowly |
| 65–74 | 100 | 85–115 | Speed and memory for new information decline faster; knowledge holds up |
| 75+ | 100 | 85–115 | Larger, more varied declines; health matters more than age itself |
Raw ability trends from Hartshorne and Germine (2015) and Salthouse (2009). Individuals vary much more than the averages.
Why every age averages 100
When a test such as the WISC (children) or WAIS (adults) is built, it is given to a large sample of each age band. Your raw score is then compared with your band: match the middle of your band and you score 100; beat 84% of it and you score 115. So a 10-year-old and a 60-year-old with the same IQ are equally far ahead of their peers, not equally good at the same puzzles.
Fluid vs crystallised intelligence
Fluid intelligence is solving new problems fast: the pattern and number puzzles on most IQ tests. It peaks in the late teens or twenties. Crystallised intelligence is what you know: vocabulary, facts and know-how. It keeps growing into the sixties. That is why older adults often do better on word questions and younger adults on timed puzzles.
Scores also change across generations
Raw scores rose by about 3 IQ points per decade during the 20th century (the Flynn effect), and the trend has flattened or reversed in some countries since the 1990s (Bratsberg and Rogeberg, 2018). Tests are re-normed every few years so that 100 stays the average.
Questions
What is the average IQ for my age?
The average IQ is 100 at every age. IQ scores compare you with people your own age, so a typical 12-year-old, 30-year-old and 70-year-old all score 100.
What is the average IQ of a 13-year-old?
100, like every age group. What changes is the raw score: a 13-year-old answers fewer questions right than a typical adult, and the test allows for that.
At what age is IQ highest?
IQ itself doesn't peak, because it is age-adjusted. Raw abilities do: speed and new-problem solving peak around 18 to 25, while vocabulary and general knowledge keep growing into the 60s (Hartshorne and Germine, 2015).
Does IQ change as you get older?
Your score relative to people your age is fairly stable from the teenage years on, but it can move by several points, especially in childhood. Schooling, health, sleep and practice all have an effect.
Can a child take an adult IQ test?
Children should take a test normed for their age, such as the WISC (6 to 16). Our online test compares everyone with an assumed average adult, so it is not accurate for children.
More: IQ score chart · Average IQ by country
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