Free IQ test

Free IQ tests vary in quality
Free IQ tests vary in quality – we provide a link to some of the better ones

There are a very large number of IQ testing resources online.  Unfortunately, very few of the online IQ tests are any good. The issue with the vast majority of online IQ tests is that they tend to over estimate test takers’ IQ. So test takers will end up thinking that they are smarter than they actually are. Although this may be good for the ego, it does not provide the test taker with a real sense of his or her cognitive strengths and weaknesses. More importantly, an IQ test is meant to give you an assessment of where you stand relative to a given population. The concept of whether or not someone is smart is a relative question. And the answer to the question lies in comparing the test taker’s IQ to that of the average person in his or her home country. So what is the point of being told by a free IQ test that you have an IQ of 140+ (genius level), when in fact your true IQ may really be around 115.

Free IQ test – you pay for what you get

Although most free IQ tests are neither very accurate or any good, some of them are, but you really have to look for them. The following site has compiled a list of free IQ tests and paid-for IQ tests that are amongst the best on the web. Click here to see the list.

At, we aim to provide the most accurate culture-fair IQ testing on the free. We do not offer a free IQ test, although you can start our test 1 for free. The price for obtaining a result is modest in comparison to several of our competitors, More importantly, we aim to provide you with a realistic estimate of your fluid intelligence for as little as $9.00 (or $15 for three tests). Professional psychologists can charge up to $1,000 for a professional assessment, and the academic literature has shown that clinical psychologists’ scoring can be highly subjective (variances of 8-10 IQ points in the scoring have been shown for the same test result!). Our IQ tests use standard scoring methodology which eliminates this problem. Test your IQ here.


Highest IQ – the measurement challenges

Highest IQ - measurement is challenging
Highest IQ measurement challenges

This articles highlights some of the challenges associated with measuring human intelligence and in particular those associated with the measurement of the highest IQ. First, unlike measuring height, weight and even human speed on a 100 meter dash, measuring IQ (and particularly the highest IQ) is a difficult endeavor. Alfred Binet – one of the pioneering forefathers of modern IQ tests – pointed out that measuring human intelligence was not as clear cut as measuring other human traits and characteristics, and that it was therefore necessary to accept a degree of error in the measurement of IQ. This assertion was one of Binet’s finest.

Another important concept in this debate is the diversity of IQ tests and associated scales. There are several different and well-respected IQ tests. Examples of well-known tests include Cattell Culture-fair IIIb, Weschler Adult Intelligence Scales (WAIS), Stanford-Binet, Woodcock Johnson, Raven’s Progressive Matrices to name a few. These individual tests have different constructs and are grounded in different although perhaps related theories on human cognition and might therefore measure different things (i.e. verbal or crystallized IQ vs. performance or fluid intelligence). Some tests are better at measuring certain types of human intelligence than others, while others do not test certain types of intelligence at all. For instance, Binet IV is one of the only well-known tests to have a quantitative reasoning scale. And subsequent revisions of the same test may change the measurement focus. Individuals may score more highly in some sections of the same test, while individuals may also score more highly on one test vs another.

To make matters more complicated, several of the above-mentioned tests use the same mean score of 100 but employ a different standard deviations which makes the comparison of test scores meaningless unless these scores are adjusted for the standard deviation of the test in question resulting in the score being converted into a percentile. For instance, the standard deviation for the Woodcock-Johnson Test of Cognitive Abilities is 16. So a score of 132 (i.e. two standard deviations above the mean score of 100) would place a test taker in the top 2% of the population.  The Cattell verbal tests on the other hand, have a standard deviation of 24, which means that a score of 148 (i.e. again two standard deviations above the mean of 100) corresponds to a score in the top 2% of test takers.

Finally, IQ tests will normally have a ceiling (i.e. Cattell verbal has a ceiling for 161 for adults which corresponds to a result in the 99.48% of the population – or one in 192 people). But someone scoring 141 on the Woodcock-Johnson test would be in exactly the same percentile. This latter point makes estimating the highest IQ in the world very difficult as estimates are then required on top of the estimations and errors that are inherent in IQ testing.

Highest IQ among geniuses of history

The interest in the highest IQ is really an interest about human genius and achievement. Would anyone care about someone with an alleged IQ of 300 (assuming this was even possible to measure) if that individual were incapable of doing anything other than scoring highly on every possible intelligence test? Probably not. So looking for the highest IQ is really about identifying human genius. You don’t need a psychologist to establish that great historical figures such as Da Vinci, Mozart, Beethoven or Graham Bell were geniuses. But highly fine-tuned IQ tests were not in existence at the time to measure their IQs the same way that Al Gore is said to have tested at 134  (but was the standard deviation 15, 16 or 24?).  So again, we are within the realm of estimates on top of estimates.

I will re-visit this topic in future posts. Meanwhile, you can have your fluid intelligence tested here.

New IQ test questions

New IQ test questions for the New Year
New IQ test questions for the New Year

Happy 2014 everyone! Wishing everyone health and happiness for the year to come. Body and mind.

At, we aim to provide the most reliable culture-fair testing on the web. IQ can be decomposed into two principal components of fluid (Gf) and crystallized (Gc) IQ. As explained previously, fluid intelligence relates to your ability to solve novel problems while crystallized intelligence is more akin to an accumulated body of knowledge that is largely acquired in formal education. So if I were to ask new IQ test questions including: what do Canada, Uganda and Iraq have in common? (One plausible answer could be that they all have populations of about 35 million people), this has to do with crystallized intelligence as you would have needed to have learned and memorized what the population of each of these countries is.  On the other hand, if I ask you what to identify the new logical symbol in the following sequence: O X O X? (The most logical answer being “O”), then this has more to do with the inherent logical reasoning ability of your brain, and is thus fluid intelligence, or an ability to solve novel problems (i.e. that you probably have never seen before).

The good news is that crystallized intelligence improves with education levels, and life experience and peaks when we reach our mid-50s. Fluid intelligence on the other hand, is believed to be genetic and peaks in our mid 20s and begins a sharp decline thereafter.

Here at, we believe that fluid IQ tests are the only kinds of tests that are applicable to a global internet audience. These culture-fair tests also control for the varying levels of education attained by individual test takers. That is, unlike crystallized IQ tests, studying for a PhD should not confer any sort of advantage on fluid intelligence IQ tests, although statistics tell us that those people who go on to complete a PhD are likely to have a higher IQ than say unskilled workers  who struggled to get through high school. We strive to provide the most realistic and accurate culture-fair testing on the web. For this reason, we are constantly thinking up new IQ test questions.

So why take an IQ test and why should we seek out new IQ test questions? More often than not, the answer might be lodged somewhere between curiosity and reaffirmation. Some test takers cite challenge and intellectual challenge with bright minds seeking to join high IQ societies to find like-minded people with curious minds. Taking online IQ tests are a good way to prepare for professionally-administered IQ tests because they diminish some of the element of surprise that you might encounter on the day.

New IQ test questions for the New Year

Off the back of the success of our culture-fair IQ test, we have developed a bank of new IQ test questions for the New Year and will be offering two more fluid intelligence IQ tests during the month of January. If you haven’t already taken our first culture-fair IQ test, you can give it a go here.

Culture-fair IQ test

Culture-fair IQ testing
Fluid intelligence tests are applicable to a global audience

Cattell and Horn distilled global intelligence (G) into two principal components: (1) fluid intelligence or Gf; and (2) crystallized intelligence or Gc.  Fluid intelligence is largely innate and represents someone’s ability to solve novel problems and can therefore be liked to raw processing power or the brain. Fluid intelligence is typically associated with the right hemisphere of the brain (i.e. simultaneous processing). Fluid intelligence peaks in our mid 20s and declines thereafter.

Crystallised intelligence, on the other hand, is associated with the body of knowledge learned in school and through formal education. People with greater schooling will on average have a much higher Gc than those people who have limited formal schooling. Because crystallized intelligence is akin to an accumulated body of knowledge, it is not surprising that Gc peaks in our mid 50s, and begins a slow decline thereafter. Crystallized intelligence is linked to the left hemisphere of the brain (sequential processing).

Most professionally administered tests will be able to measure both types of intelligence. However, different questions and/or tests can be used to measure each type of intelligence. Similarly, in the world of online IQ testing, some tests will be better designed for measuring either Gf or Gc.

From an online testing standpoint (where your audience is global), it would be impossible design a scientific test for Gc that does not suffer from cultural bias – that is, it is not possible to design a culture-fair IQ test for crystallized intelligence when you are testing a global audience. In fact, anything that tests a body of knowledge may favor some groups over others. For instance, a test which asks: “who was the third president of the United States” (Thomas Jefferson is the answer by the way), is a question which is more likely to be answered correctly by American test takers than say, Nigerian test takers. And even then, American history majors may be at a significant advantage in getting this answer right than say, American Psychology majors.

Word definitions or describing certain concepts, also suffers from cultural bias due not only to language fluency problems (i.e. should we be ascertaining French-speakers with questions written in English? Of course not), but also due to the fact that different countries and languages use words in different ways. (e.g. in English, you can say “I love pizza”. But you cannot say “Yo amo Pizza” in Spanish, instead, you would say, “A mi me gusta la pizza”, which essentially means that you like pizza). So a crystallized intelligence test cannot be a culture-fair IQ test.

A Culture-fair IQ test for a global audience

For this reason, fluid intelligence tests are the only types of IQ tests that can be described as ‘culture-fair IQ tests’. Fluid reasoning tests such as our test, Raven’s Progressive Matrices (RPM) or Cattell Culture-fair IIIa tests are based on reasonably abstract picture sequences and missing patterns. It can perhaps be argued that knowledge of geometry (or lack thereof) can induce a cultural bias, but it remains that a triangle is a triangle (3 sides, and internal angles totaling 180 degrees) in every nation on earth.

When it comes to testing the IQ of a global internet audience, a culture-fair IQ test is the only kind of test which has scientific merit to ascribe rankings between different nations (i.e. you can administer the exact same test to everyone, with only the instructions requiring translation), and the only types of culture-fair IQ tests that exist will test Fluid intelligence (Gf), which includes Visual Processing ability (Gv), Processing Speed (Gs) and Working Memory (Gsm). Gv, Gs and Gsm are all sub components of fluid intelligence.

Take our culture-faire IQ test HERE.