- The average IQ is 100 at every age, by design.
- Those charts usually confuse raw ability with the normed score.
- Your normed IQ stays fairly stable, but the underlying abilities shift with age.
- A child's IQ is never compared to adults; it is normed against same-age children.
- No, the average IQ for seniors is still 100 because their scores are normed against other seniors.
What is the average IQ by age?
The average IQ is 100 at every age, by design. IQ tests are age-normed, meaning your raw answers are compared only against people in your own age group before a score is assigned. This calibration forces the average to land at 100 for children, teens, adults, and seniors alike.
Why do 'IQ by age' charts show different numbers?
Those charts usually confuse raw ability with the normed score. A 7-year-old and a 30-year-old can both have an IQ of 100 despite hugely different raw knowledge, because each is scored against same-age peers. Charts that show IQ peaking at a certain age are mixing up underlying cognitive performance with the standardized 100-centered scale.
Does IQ change as you get older?
Your normed IQ stays fairly stable, but the underlying abilities shift with age. Fluid intelligence (on-the-spot reasoning and problem-solving) tends to peak in the early 20s and then declines slowly. Crystallized intelligence (vocabulary, facts, and accumulated knowledge) keeps rising into your 60s, often offsetting the fluid decline.
How is a child's IQ measured against adults?
A child's IQ is never compared to adults; it is normed against same-age children. A 6-year-old scoring 115 is performing better than about 84% of other 6-year-olds, not 84% of grown-ups. This is why age-appropriate tests like the WISC exist separately from adult tests like the WAIS.
Do older adults have lower IQs?
No, the average IQ for seniors is still 100 because their scores are normed against other seniors. While raw fluid-reasoning speed declines with age, crystallized knowledge stays strong or grows. Age-norming ensures a 75-year-old and a 25-year-old are each measured fairly within their own cohort.
Age-Normed Average IQ Across the Lifespan
| Age group | Average (normed) | Normal range | Note |
|---|---|---|---|
| Children (5-12) | 100 | 85-115 | Normed against same-age peers, not adults |
| Teens (13-17) | 100 | 85-115 | Fluid reasoning still developing toward its peak |
| Adults (18-29) | 100 | 85-115 | Fluid intelligence near its lifetime peak |
| Adults (30-49) | 100 | 85-115 | Fluid begins slow decline; crystallized keeps rising |
| Adults (50-69) | 100 | 85-115 | Crystallized knowledge often at its strongest |
| Seniors (70+) | 100 | 85-115 | Normed within cohort; vocabulary stays robust |
β People also ask
What Is a Good IQ Score?
An IQ of 100 is exactly average; 110-119 is above average, 120 and up puts you in the top 10% (a genuinely 'good' score), and 130+ is considered gifted. IQ is built on a normal distribution with a mean of 100 and a standard deviation of 15, so most people cluster near the middle.
What Is a Good IQ Score? βIQ Percentile Chart: What Percentile Is My IQ?
Your IQ percentile tells you the share of people you scored higher than: an IQ of 100 is the 50th percentile, 115 is about the 84th, 120 is roughly the top 10%, and 130 is roughly the top 2%. The table below maps every major IQ band to its classification, percentile, and share of the population.
IQ Percentile Chart: What Percentile Is My IQ? βAre Online IQ Tests Accurate?
A well-designed online IQ test gives a reliable estimate of your reasoning ability, but it is not a clinical diagnosis β only a proctored test like the WAIS or Stanford-Binet provides that. This test is built on Raven's Progressive Matrices and CHC theory, scored on the standard scale (mean 100, SD 15), with an internal reliability (Cronbach's alpha) of about 0.85-0.92.
Are Online IQ Tests Accurate? βCan You Increase Your IQ?
You can meaningfully sharpen reasoning skills, working memory, and test performance through training and education, but raising your underlying general intelligence (g) substantially and permanently is not well supported β core g is largely heritable. The honest answer is that some gains are real and some popular claims are overstated.
Can You Increase Your IQ? βGenius IQ Level: What Number Counts as Genius?
A 'genius' IQ traditionally starts at 140, while 130 and above is labeled 'very superior' on modern tests. Scores that high are extremely rare, and the famous IQ numbers you see for historical figures are almost always estimates, not measured results.
Genius IQ Level: What Number Counts as Genius? β