Welcome! What is the average IQ by age? (For example, that of the IQ of a 12 year old boy). We answer all your questions here.

Note: Please keep in mind that while IQ tests can provide useful insights into a child’s cognitive development, they also come with several inherent issues. Factors such as cultural bias, test anxiety, socioeconomic status, and educational disparities can influence test results, making IQ scores an incomplete indicator of a child’s full intellectual potential.

We have added a detailed chart comparing average IQ scores across various ages, setting the baseline IQ of 100 at age 18:

What is the Average IQ by Age for Children?

Age	Average IQ (18 = 100)	Notes
2	20	Early cognitive development
3	30	Rapid language development
4	40	Basic problem-solving skills
5	45	Early reasoning abilities
6	50	Improved cognitive processing
7	60	Rapid cognitive skill growth
8	70	Developing complex reasoning
9	75	Increased cognitive complexity
10	80	Significant cognitive maturity
11	85	Advanced logical reasoning
12	88	Approaching teenage cognition
13	90	Early teenage cognitive skills
14	93	Higher-order reasoning forming
15	95	Near-mature cognitive function
16	97	Approaching adult intelligence
17	99	Nearly mature cognition
18	100 (Baseline)	Adult-level intelligence
20	100	Cognitive peak
25	100	Stable cognitive performance
30	100	Stable cognitive function
35	100	Peak cognitive efficiency
40	99	Minor changes begin
45	98	Slight cognitive adjustments
50	97	Gradual cognitive shift
55	95	Noticeable memory changes
60	93	Decreased processing speed
65	90	Cognitive speed declining
70	87	Continued slight decline
75	84	Memory and fluid intelligence decline
80	80	Noticeable cognitive decline
85	75	Increased cognitive decline
90	70	Significant cognitive decline

This chart demonstrates relative cognitive development and decline across different ages compared to an 18-year-old baseline IQ of 100.

Cognitive Abilities and Aging

While overall IQ remains stable, specific cognitive skills can vary significantly across different stages of life:

• Young adulthood (18–35 years): Peak cognitive performance in fluid intelligence (reasoning, problem-solving).
• Middle adulthood (36–55 years): Accumulation of knowledge (crystallized intelligence) typically continues to grow.
• Older adulthood (56+ years): Some declines may occur in processing speed and memory, but crystallized intelligence often remains stable or improves due to accumulated knowledge and experience.

These changes reflect natural variations in cognitive abilities across the lifespan, influenced by education, occupation, health, and lifestyle rather than significant shifts in the standardized IQ score itself.

Cognitive Development Across the Lifespan

Cognitive performance typically increases from childhood into early adulthood, stabilizing around early adulthood (mid-20s to mid-30s). Intelligence in later adulthood often benefits from accumulated knowledge and experience, despite potential declines in processing speed or memory in advanced age. Cognitive abilities reflect a combination of innate potential and environmental influences like education, socioeconomic status, health, and lifestyle.

Global IQ Statistics and Disparities

Global Average IQ

The global average IQ is estimated to be around 89, based on international studies. However, significant variations exist, largely influenced by socioeconomic factors, educational standards, healthcare access, and nutrition.

Country	Average IQ	Notes
Japan	~106	Strong educational infrastructure
Hong Kong	~106	Emphasis on rigorous education
United States	~98	Slightly below standardized mean
China	~104	Significant educational efforts
Botswana	~70	Challenges in educational access
Nepal	~78	Improved estimates in recent data

Factors contributing to these variations include:

• Education: Quality education directly correlates with higher IQ scores.
• Socioeconomic Status: Economic stability enhances cognitive development opportunities.
• Healthcare: Adequate healthcare ensures optimal cognitive and physical development.
• Nutrition: Adequate nutrition during formative years supports optimal brain development.

Diving into US IQ Averages

What is the Average IQ in USA (United States)?

The average IQ in the United States is about 98, slightly below the global standardized mean of 100. This average reflects disparities influenced by education, socioeconomic factors, and regional differences.

State-wise IQ Comparison

States with robust educational systems typically exhibit higher average IQ scores:

• Massachusetts (~104)
• New Hampshire (~104)
• Vermont (~103)

States with better-funded education systems and higher socioeconomic status usually demonstrate higher IQ averages.

Influence of Education on IQ Scores

Education significantly impacts IQ scores. Higher-quality education promotes cognitive development and contributes to higher IQ scores, explaining variations among different states and regions within the U.S.

IQ Classifications Beyond Averages

Examples of High IQ Classifications

IQ classifications illustrate varying cognitive capabilities:

IQ Score Range	Classification	Population Percentage
130+	Very Superior	~2%
120–129	Superior	~7%
110–119	High Average	~16%
90–109	Average	~50%
80–89	Low Average	~16%
70–79	Borderline	~7%
Below 70	Extremely Low	~2%

Mensa, a society for high-IQ individuals, typically requires an IQ in the top 2% (around 132 or higher).

Gender Differences in IQ Scores

Average IQ scores exhibit minimal differences between genders. Both men and women have average IQs centered around 100, with minor variations typically influenced by environmental factors, education, and socioeconomic status. The overall distribution of IQ scores is nearly identical for both genders, emphasizing cognitive equality.

IQ and Life Success

While IQ scores correlate strongly with academic success, they do not singularly predict life success. Intelligence is multifaceted, including emotional intelligence, creativity, resilience, and social skills.

Limitations of IQ as a Predictor

IQ is predictive of academic achievement but has limitations in forecasting success in areas requiring creativity, emotional intelligence, interpersonal skills, and resilience. Successful individuals in business, arts, and entrepreneurship often excel beyond what standardized IQ tests measure.

Factors Influencing Success Beyond IQ

Life success involves several interrelated factors:

Factor	Influence on Success	Examples
IQ	Academic and analytical success	Higher IQ correlates with better academic outcomes
Emotional Intelligence	Social and interpersonal success	Better relationships and emotional stability
Socioeconomic Status	Opportunity and resource access	Enhanced educational and career opportunities
Health and Nutrition	Cognitive and physical performance	Supports overall productivity and learning capacity

In conclusion, while IQ is a valuable tool for assessing cognitive ability, it is essential to recognize its limitations and consider broader factors when evaluating individual potential and predicting overall life success.

Frequently Asked Questions (FAQs) about IQ Scores.

What is a good IQ score?

IQ scores between 90 and 109 indicate average intelligence. The standard average IQ is set at 100. Here’s a detailed breakdown:

IQ Score Range	Classification
Above 140	Genius or nearly genius
120–140	Superintelligence or gifted
110–119	Superior or above-average intelligence
90–109	Average intelligence
80–89	Lower average or dullness
Below 70	Intellectual disability or “feeble-minded”

Only about 2% of the population scores above 130, placing them in the gifted or genius category. Historical geniuses like Albert Einstein, Stephen Hawking, and Ada Lovelace are estimated to have had IQs around 160.

Is an IQ of 120 good?

Yes, an IQ score of 120 is considered very good. It indicates superior or above-average intelligence, placing you in roughly the top 10% of the population.

Can I train for an IQ test?

You cannot significantly change your innate intelligence, but you can improve your IQ test performance through practice. Engaging regularly in problem-solving exercises, puzzles, brain-training games, and learning new skills or languages can enhance cognitive functioning and potentially improve your test results.

What’s the difference between aptitude tests and IQ tests?

Aptitude tests:

• Measure specific skills or abilities.
• Do not factor age into scoring.
• Provide scores for individual skill categories.
• Primarily used for job selection or skill assessment.

IQ tests:

• Measure general cognitive ability and intellectual potential.
• Scores are adjusted by age.
• Provide a single general intelligence score.
• Commonly used for educational placement, psychological assessments, and research.

Is there an IQ difference between men and women?

Research shows no significant difference in average IQ scores between men and women. Both genders average around 100, though more men are found at both extreme high and low ends of the IQ distribution. Historical assumptions about intelligence based on gender or brain size have been disproven by scientific studies.

Does average IQ change over time?

An individual’s IQ remains relatively stable throughout adulthood. However, cognitive abilities such as memory or processing speed can vary. On a population level, average IQ scores have increased over decades—a phenomenon known as the Flynn Effect—attributed to improvements in education, health, and access to information.

Is average IQ different by country?

Yes, average IQ scores differ across countries, typically influenced by educational quality, health standards, socioeconomic conditions, and nutrition. Countries like Japan, Taiwan, and Singapore have higher average IQ scores (around 106), while less developed countries tend to have lower averages. The United States has an average IQ of around 98.

What IQ score indicates intellectual disability?

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM):

• IQ 71–84: Borderline intellectual functioning
• IQ 50–70: Mild intellectual disability
• IQ 35–49: Moderate intellectual disability
• IQ 20–34: Severe intellectual disability
• Below IQ 20: Profound intellectual disability

How can someone improve their IQ score?

While innate intelligence is largely fixed, you can boost your IQ test performance by:

• Learning new skills (e.g., music, languages)
• Regularly solving puzzles and playing brain-training games
• Reading extensively and continuously acquiring knowledge
• Enhancing verbal and logical reasoning skills
• Maintaining a healthy lifestyle with nutritious food, exercise, and sufficient rest

What is the Average IQ by Age for Children:

As you can see on this chart, the average IQ for kids will have to be measured against a baseline age, here 18.