How Do I Know My IQ? IQ Ranges & Average Scores

How Do I Know My IQ
IQ tests administered by a trained psychologist provide more reliable results than online tests. Learn about IQ ranges and average scores by age

IQ tests are standardized assessments used to evaluate reasoning skills and other cognitive abilities. However, although there are many online IQ tests, only those administered by a trained psychologist can provide reliable results.

What are IQ ranges?

Most people score between 70, 130, with 100 being the average. A score over 90 is considered average, over 130 is higher than average, and 70 or lower is lower than average.

  • 110-119: Above average
  • 120-140: Gifted or superintelligent
  • Over 140: Genius or near genius
  • 80-89: Below average
  • 70-79: Low or borderline deficient
  • Under 70: Definite feeble-mindedness

What are average IQ scores by age?

Studies have shown that average IQ scores by age group are as follows: 

  • Ages 16-17: 108
  • Ages 18-19: 105

During the next few years of adult life, there may be a drop in IQ, with scores typically rising again after ages 20-30:

  • Ages 35-44: 101
  • Ages 45-54: 106
  • Ages 55-64: 109
  • Ages 65-69: 114
  • Ages 70-74: 119

9 reliable IQ tests

1. Wechsler adult intelligence scale (WAIS)

The WAIS is one of the most trusted adult IQ tests that measures cognitive abilities, intended for ages 16 and above. WAIS-III is the most recent version of the test and takes about 60-75 minutes to complete. Although the free online versions evaluate the same skills and typically only take about 15-30 minutes to complete, they are not as reliable as the official version.

2. Mensa practice test

Mensa is the world's largest and oldest high-IQ society, and only those who score in the 98th percentile or higher are accepted. The Mensa practice test asks questions that are aligned with the skills commonly tested by IQ assessments and provides an equivalent score that corresponds to a person’s IQ range. Although just 30 minutes long, the practice test gives you a good idea of how you would do on the official admissions test.

3. Stanford-Binet intelligence scales (SBIS)

This is currently one of the most widely used and highly regarded IQ tests. The most recent edition, the SB-V assessment, is divided into 10 subtests, each of which takes about 5 minutes to complete. The subtests cover each of the five cognitive ability factors in depth:

  • Fluid reasoning
  • Knowledge
  • Quantitative reasoning
  • Visual-spatial processing
  • Working memory

Although the official Stanford-Binet is not available online, several online IQ tests have been inspired by and based on the same skills. The online versions typically consist of 30 questions and take very little time to complete.

4. Brain metrics initiative (BMI) online IQ test

The test advertises itself as the most accurate online IQ test available in the United States. The test consists of only 20 questions and provides an IQ score, IQ certificate, and performance report outlining intellectual strengths and weaknesses. This test is widely regarded as one of the more reliable online IQ tests because the distribution of results is comparable to official IQ tests, such as the WAIS and the Stanford-Binet, whereas many other online IQ tests may exaggerate scores.

5. Woodcock-Johnson (WJ) test of cognitive abilities

The test can be taken by children as young as 2 years old and adults up to 90 years old. Unlike many other IQ tests, the WJ requires reading and writing and is thought to provide a very detailed understanding of intelligence, with each subtest taking about 5 minutes to complete.

6. IQ test labs

This is a timed assessment that consists of 30 questions. After 15 minutes, it is automatically scored. The test assesses the same abilities as some of the most popular IQ tests, such as visual or spatial abilities and logical reasoning. Score reports will indicate your strengths and weaknesses.

7. Raven’s progressive matrices (RPM)

The RPM is the world's leading nonverbal intelligence test and requires no reading or writing to complete. Although the exam is not timed, it typically takes 45 minutes to complete.

8. Psychtests

Psychtests are a set of IQ tests that assess several aspects of intelligence, including logical reasoning, math skills, and general knowledge. They evaluate your ability to categorize, analyze, and determine relationships between objects and ideas.

9. Rutherford intelligence analysis

Created by Duke and Harvard University psychology experts, this test claims to be the most accurate online IQ assessment. In terms of question format and difficulty, the test was designed to be representative of official IQ tests, and questions are constantly calibrated for accurate scoring.

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What are the differences between aptitude tests and IQ tests?

Aptitude tests

Most aptitude tests assess a specific set of skills while cognitive aptitude tests can assess a wide range of abilities and provide individual scores for each. Standardized tests or game-based assessments:

  • Measure specific areas of intelligence
  • Does not factor in age 
  • Scores for each category
  • Highly predictive of job performance
  • Most commonly used in pre-employment testing

IQ tests

IQ tests are usually standardized tests that cover a wide range of topics, such as logical, visual, spatial, classification, analogical, and pattern-driven questions. IQ scores are calculated as the difference between the test score and the average test score of people of the same age. IQ tests:

  • Measure general intelligence
  • Factors in age
  • Provides one overall score
  • Moderately predictive of job performance
  • Most commonly used in research and education
References
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Bearce KH. Chapter 8: Intelligence. Personal Communication. 2009. https://www.mccc.edu/~jenningh/Courses/documents/Handout-Intelligence_000.pdf

Psychology. Measures of Intelligence. https://opentextbc.ca/psychologyopenstax/chapter/measures-of-intelligence/

Variations in psychological attributes. In Psychology. https://ncert.nic.in/textbook/pdf/lepy101.pdf

Healthline. IQ Testing. https://www.healthline.com/health/iq-testing

Cherry K. What Is an IQ Test? Very Well Mind. https://www.verywellmind.com/how-are-scores-on-iq-tests-calculated-2795584