When answering the question of what is the average IQ by age, 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?

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

Please note that IQ scores in tests are standardized to maintain an average of 100 across all ages, meaning that regardless of age or gender, the midpoint IQ score is consistently set at 100. Tis number, 100, refers to the average IQ score at that age compared to others at that age.  With that in mind, the technically correct answer to ‘What is the Average IQ for a 12 Year old‘, or another age, will always be 100, as you can see below.

What is the average IQ for a 2-year-old Boy?

The average IQ score for a 2-year-old boy is around 100, with a normal range typically between 85 and 115.

What is the average IQ for a 2-year-old Girl?

The average IQ score for a 2-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 3-year-old Boy?

The average IQ score for a 3-year-old boy is around 100, and a normal range is typically 85 to 115.

What is the average IQ for a 3-year-old Girl?

For 3-year-old girls, the average IQ score is approximately 100, with the normal range being 85 to 115.

What is the average IQ for a 4-year-old Boy?

The average IQ for a 4-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 4-year-old Girl?

A 4-year-old girl typically has an average IQ score of 100, with a normal range generally from 85 to 115.

What is the average IQ for a 5-year-old Boy?

The average IQ for a 5-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 5-year-old Girl?

A 5-year-old girl typically has an average IQ score of 100, with a normal range generally from 85 to 115.

What is the average IQ for a 6-year-old Boy?

The average IQ for a 6-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 6-year-old Girl?

A 6-year-old girl typically has an average IQ score of 100, with a normal range generally from 85 to 115.

What is the average IQ for a 7-year-old Boy?

The average IQ for a 7-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 7-year-old Girl?

The average IQ for a 7-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for an 8-year-old Boy?

The average IQ for an 8-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for an 8-year-old Girl?

The average IQ for an 8-year-old girl is approximately 100, with a normal range generally from 85 to 115.

hat is the average IQ for an 11-year-old Girl?

The average IQ for an 11-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 12-year-old Boy?

The average IQ for a 12-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 12-year-old Girl?

The average IQ for a 12-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 13-year-old Boy?

The average IQ for a 13-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 13-year-old Girl?

The average IQ for a 13-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 14-year-old Boy?

The average IQ for a 14-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 14-year-old Girl?

The average IQ for a 14-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 15-year-old Boy?

The average IQ for a 15-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 15-year-old Girl?

The average IQ for a 15-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 16-year-old Boy?

The average IQ for a 16-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 16-year-old Girl?

The average IQ for a 16-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for a 17-year-old Boy?

The average IQ for a 17-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for a 17-year-old Girl?

The average IQ for a 17-year-old girl is approximately 100, with a normal range generally from 85 to 115.

What is the average IQ for an 18-year-old Boy?

The average IQ score for an 18-year-old boy is 100, with a normal range typically between 85 and 115.

What is the average IQ for an 18-year-old Girl?

Similarly, the average IQ score for an 18-year-old girl remains at 100, with a normal range generally from 85 to 115.

Understanding IQ Score Ranges:

• 130 and above: Very Superior
• 120–129: Superior
• 110–119: High Average
• 90–109: Average
• 80–89: Low Average
• 70–79: Borderline
• 69 and below: Extremely Low

IQ scores are standardized to maintain an average of 100 across all ages, meaning that regardless of age or gender, the midpoint IQ score is consistently set at 100. This standardized scoring helps provide a stable reference point for assessing cognitive abilities across various age groups.

While these tests can offer valuable insights into cognitive development, they also have several limitations. Factors such as cultural biases, socioeconomic disparities, test anxiety, educational inequalities, and nutrition significantly affect IQ scores, making them only one part of a broader understanding of intelligence.

What is the Average IQ by Age?

The concept of IQ scores is standardized, meaning the average is set at 100 across all age groups. However, cognitive abilities and scores can vary throughout a person’s lifespan due to developmental and environmental factors.

Typical IQ Scores in Different Age Brackets

Here’s a corrected and fact-checked breakdown of typical IQ score trends across various age groups:

IQ scores are specifically designed not to change significantly with age because they are standardized and norm-referenced. This means IQ tests compare individuals against their age group peers rather than against an absolute standard of intelligence. As people age, their cognitive abilities develop, but IQ tests adjust the scoring to maintain a consistent average (100) at every age.

In other words, an IQ test for a 10-year-old measures intelligence relative to other 10-year-olds, and for a 50-year-old relative to other 50-year-olds. While an individual’s specific cognitive skills may evolve, their overall relative position compared to their peers typically remains stable, resulting in little change in their standardized IQ score.

This approach ensures consistency and comparability across different ages and developmental stages.

With this in mind, averages IQ scores do change by age compared to all other ages. We have included a chart below, where we have set an 18 year old as the baseline 100 IQ to see how age compares to the baseline:

Here’s a comparative chart illustrating how IQ performance by age compares to an 18-year-old baseline set at 100:

This chart shows approximate cognitive development relative to an 18-year-old as a reference point, highlighting how certain cognitive abilities evolve over time, rather than representing standardized IQ test scores.

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.

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:

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:

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:

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