IQ Statistics
Average IQ by Age
The short answer: the average IQ is 100 at every age. Modern IQ tests are age-normed, which means your score compares you with people your own age. A 70-year-old and a 25-year-old who both score 100 are each exactly average for their age group.
What does change with age is the mix of abilities underneath. Research consistently finds that fluid reasoning (solving new problems, spotting patterns, working quickly) peaks in your 20s and slowly declines, while crystallized knowledge (vocabulary, facts, experience) keeps growing well into your 50s and 60s.
How abilities shift with age
Approximate raw ability compared with a 20–34 year-old reference group (100). Everyone's normed IQ average is still 100.
| Age | Average IQ | Fluid reasoning | Knowledge |
|---|---|---|---|
| 16–19 | 100 | 98 | 96 |
| 20–24 | 100 | 100 | 99 |
| 25–29 | 100 | 100 | 100 |
| 30–34 | 100 | 99 | 101 |
| 35–44 | 100 | 97 | 102 |
| 45–54 | 100 | 94 | 103 |
| 55–64 | 100 | 90 | 103 |
| 65–74 | 100 | 86 | 102 |
| 75+ | 100 | 81 | 99 |
Once enough people in each age group take the FreeIQTest.co test, we'll add our own averages to this table.
What this means for you
- Your score is fair at any age. Because it's compared with your own age group, a 60-year-old isn't penalized for slower reaction times.
- Different ages, different strengths. Younger adults tend to shine on speed and pattern puzzles; older adults on vocabulary and general knowledge.
- Decline isn't destiny. Staying mentally active, sleeping well, exercising, and learning new skills are all linked to better cognitive aging.
How do you compare for your age?
Take the FreeIQTest.co test and see your age-adjusted IQ score and percentile.
Take the IQ TestSee also: Average IQ by country
Sources & notes
Fluid and knowledge figures are approximations interpolated from cross-sectional research, not values from a single published table.