An IQ, or Intelligence Quotient, is a score derived from a standardized test measuring various elements of a person’s intelligence. Most modern tests aim to measure a person’s ability to process visual-spatial and auditory information, their processing speed, short term memory, abstract reasoning, and past learning. Clearly, measuring all of these components is an enormous undertaking, and that’s why there is such a wide variety of IQ tests, and why they are constantly being updated and refined.

Once a subject completes their version of the test, their score is then compared to the population as a whole to determine where their level of intelligence stands in comparison to a larger population (often adjusted for age or other demographics).

An IQ Test is a means to determine a person’s intelligence. The first test was invented by French psychologist Alfred Binet. His initial test spawned many of today’s many IQ test variations. The most popular of these tests today are the Wechsler tests, which include variations for different age groups and other demographic groups. One common theme among IQ tests is that they conform to a standard distribution of scoring, which in graph form appears as a bell curve. The two most popular IQ tests have standard distributions of 15 (Wechsler) and 16 (Stanford-Binet). 

Depending on the type of test you take, IQ test questions vary greatly as they try to assess different aspects of fluid and crystallized intelligence. Some tests, like the Cattell Culture Fair Test, try to assess intelligence using largely visual formats to diminish the possible cultural, language, or social biases in the questions. Depending on the test you take, you can find questions that focus on things like vocabulary and reading comprehension, while others will make you solve visual puzzles or reorganize blocks into shapes. 

We measure IQ for many reasons, but two primary reasons are to better understand how our minds work, and secondly to help place people for educational and job purposes. These tests are often used to identify children for learning disabilities or advanced educational placement and are also used to evaluate a person’s potential aptitude for certain careers. They also assist in evaluating intellectual strengths and weaknesses, creative problem solving, and thinking under pressure. IQ test scores are also used as a deciding factor for admission to certain high intelligence groups and societies like MENSA, and also for evaluating applicants for specialized jobs.

High IQ Societies like Mensa limit their membership to include only individuals who have scored in the 98th percentile on an approved intelligence quotient (IQ) test.

Mensa is the largest, oldest and most renowned high intelligence society in the world. It is also incredibly difficult to get into. To qualify for membership to Mensa, you must score in the top 2% of all people taking an approved intelligence or aptitude test. This sole requirement is usually met with an IQ test score of approximately 130 or above. Eligible candidates for Mensa membership need to supply proof of their qualifying test scores and pay applicable membership dues to join. If you’re interested in finding out if you are Mensa material, our practice test can help you prepare for the actual Mensa exam. Please note, the tests on this site are for entertainment purposes only. You won’t find a real IQ test free online, but you can learn more about the different types of IQ tests available on this site and contact a local organization or professional psychologist who can help you schedule one. 

Generally, once a person achieves an IQ of 140 or over they’re considered to have genius or near-genius intelligence. A score of 145 is three standard deviations above the average IQ, and only 0.1% of the population fall into this category. The difficulty, however, is that standard IQ tests often struggle to measure IQs that range much higher than a score of 145. Without a highly qualified professional who has dealt with such high IQ individuals previously, their scores may not be calculated correctly. To be considered as someone with “very superior” intelligence, you would need a score of 130 or above, only two percent of test takers score within the “very superior” level.

Most licensed psychologists can administer an IQ test and many university Psychology Departments will administer them in controlled settings.  The easiest way, however, is to take the practice IQ Test on our site.  If you prefer a paper version, download our IQ test PDF.