— IQ across the lifespan
Average IQ at age 5
The average IQ at age 5 is 100 by definition. IQ tests are age-normed — each person's score is compared against the typical performance of their own age group, not against an absolute scale. This means a "100" at age 5 is calibrated to whatever typical 5-year-olds actually score.
What's actually happening cognitively at 5
→Pause. Find out YOUR IQ before you keep reading.Age 5 falls in Early childhood — characterized by rapid working-memory development, fluid intelligence still consolidating, pattern recognition emerging. The age-normed IQ of 100 conceals real developmental shifts: certain cognitive abilities peak at different ages, even though the test's scoring system rescales everyone to a mean of 100.
Fluid vs crystallized intelligence at age 5
→Curious how YOU score? 20-min calibrated test.IQ has two large components that age differently:
- Fluid intelligence (raw reasoning, pattern recognition, novel problem-solving) is still rising at age 5 and will peak between 18 and 22.
- Crystallized intelligence (vocabulary, accumulated knowledge, expertise) is still rapidly accumulating at age 5.
What "average" looks like at age 5
→The numbers above? Find out where YOU land.An IQ of 100 at age 5 means typical performance for the 5-year-old age cohort on the following tasks:
- Vocabulary and verbal comprehension at a developmentally typical level for elementary/middle school
- Working memory — typical capacity of holding 5-7 items active at once
- Processing speed — near lifetime peak
- Abstract pattern recognition — typical for the cohort
Common misconceptions about IQ and age
→Knowing about IQ ≠ knowing yours. Take the test.- "My IQ is going down as I age." Your age-normed IQ stays roughly constant — the test rescales for your cohort. What changes is raw fluid performance; crystallized knowledge typically increases.
- "Kids who score higher are more intelligent than adults." Age-normed IQ is the only fair comparison. A 12-year-old scoring 130 and a 50-year-old scoring 130 both rank at the 98th percentile within their own age group.
- "Peak IQ is at age 25." Different components peak at different ages: working memory and processing speed in the early 20s; verbal/crystallized knowledge in the 50s-60s; composite age-normed IQ is roughly stable from early adulthood through middle age.
Frequently asked
→Stop reading. Start testing →What is the average IQ at age 5?
100 by definition. All standard IQ tests (WAIS, Stanford-Binet, WISC) are age-normed so the mean is always 100 for the specific age cohort being tested.
Does IQ drop with age?
Age-normed IQ stays roughly constant from early adulthood through middle age. Raw fluid intelligence declines after age 25-30; crystallized intelligence grows until 50-65; both are baked into the age-normed score.
Can my child be tested for IQ at age 5?
Reliable IQ testing typically begins around age 6. Before that, infant cognitive assessments use different scales (Bayley, Mullen) that don't predict adult IQ well.
Other ages
→Pause. Find out YOUR IQ before you keep reading.Related reading
→Curious how YOU score? 20-min calibrated test.Sources: Salthouse, T. A. (2010), Selective review of cognitive aging; Cattell, R. B. (1971), Abilities: Their Structure, Growth, and Action; WAIS-IV and WISC-V technical manuals.
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