It is our mission to provide the most accurate online intelligence test in the
world. This test is free of charge for anyone using it for non-professional or personal reasons.
Vision
This test is aimed at giving everyone in the world a fair, transparent, and accurate method to determine
their intelligence in a standardized way.
Fair
It is our goal to create a level playing field for everyone in the world:
by providing a culturally fair test with questions that use the simplest language and academic knowledge. We
believe it is impossible to create a test free of cultural bias, but we try to make it as fair as possible.
by giving people the opportunity to take the test as often as they’d like. Some people have performance
anxiety, had a sleepless night, or just need a bit more practice than others to feel comfortable when taking
the test. We don’t think these things should be reflected in an intelligence score. We believe everybody
should have enough chances to reach their ‘true’ intelligence score potential.
by providing open access to more questions across vast numbers of categories than anyone in the world could
ever memorize. Plus, everybody worldwide has the same access to the questions that are used in the test.
Transparent
We believe that personal intelligence is a delicate subject. Therefore, we want to be clear that an
intelligence score will always reflect subjective choices about what intelligence is. It is our goal to be
clear about these choices:
by providing open access to all the questions that are used to determine someone's intelligence. After every
test, we provide the metadata from the questions that have been answered by the candidate (average ratio
correct and average time needed from all other users who answered the questions).
by being open about our scoring method. It is our goal to make the scoring method as simple as reasonably
possible, to ensure that everybody understands how they can reach their own best results.
by giving free access to test results to all non-professional users. We believe that everybody should be
able to see the results of any test they have taken. Therefore, we will never ask for a payment from
individual users for them to see their test results.
Accurate
We make it our mission to provide the most accurate online intelligence test in the world:
By constantly calculating the predictive value of every question for every user to give the most accurate
estimate of someone's intelligence in as little time as possible.
By testing on an immense scale. Our test has been taken by more than 2 million users from all over the
world. This method provides a very accurate data compilation of all the individual questions and test
results that are used to determine the intelligence score.
By constantly updating all the content. We add new questions and categories while removing questions that
have a lesser predictive value on a daily basis.
Scoring method
Goals of the scoring method
It is our goal to provide a clear scoring method that:
Is easy to understand
Rewards correct answers
Rewards working quickly
Discourages guessing
Adaptive Test
The level of the questions in the test is adjusted to your level during the test. If you answer the first
question correctly, the next question will be a little more difficult. If you give the incorrect answer to a
question, the next question will be a little bit less difficult.
Data per question
For each question, we track the average time that it takes people to answer the question (average time) and
the percentage of people who answered the question correctly (percentage correct).
Points earned per correct answer
For every question you answer correctly you earn:
Average time * (1 - percentage correct) points
This ensures you earn more points for answering a difficult question correctly than for answering an easy
question correctly. It also makes sure you earn more points for questions that take the average user a
longer time to answer.
‘Points’ lost per correct answer
For every question you answer incorrectly you lose:
Average time * percentage correct points
This ensures you lose more points for answering an easy question incorrectly than for answering a difficult
question incorrectly.
‘Raw score’
You get 20 minutes to earn as many points as possible. The total amount of points you have earned during the
test is called your “raw score”.
Percentile score
We compare your raw score to the raw scores of all of the other users who finished the test in order to
calculate your “percentile score”. This calculation reflects the percentage of users who finished the test
and had a lower raw score than yours.
For example, a percentile score of 67% means that you performed better (earned more points) than 67% of all
people who ever finished the test.
IQ score
From the percentile score, we calculate your IQ score. We make this calculation of your IQ score with a
median of 100 and a standard deviation of 15. This is the same calculative method used by other IQ testers,
such as the Wechsler Adults Intelligence Scale.
Item Response Theory
Since not all users answer the same questions and some questions will be answered more or less frequently by
users with a higher or a lower intelligence level, mathematical models are used to give the most accurate
estimation of the difficulty of the questions. For the sake of clarity, we use the term “average percentage
correct” without mentioning the Item Response Theory models that are used to calculate this percentage.
Limitations to online intelligence tests
We are well aware that there are certain limitations to the accuracy of online intelligence tests. It is our
goal to be open about these limitations while limiting their impact as much as possible.
The main limitation of online intelligence tests and the main solutions we see:
People don’t take the test themselves
We provide free access to our intelligence tests for people to be able to assess their own intelligence.
This means each person has the responsibility to take the tests without help from others. Otherwise, you are
just fooling yourself. So, we encourage each person to take the test without help. If people want to help
you with your test, encourage them to take their own test.
People memorize the test
Most intelligence test publishers keep their questions “secret”. They do this to limit the number of people
who have knowledge about the questions before they take the test. We don’t believe in this strategy. In our
digital age, it is very difficult to keep such content secret from a bigger public. Some people will have
more knowledge about the content of the questions than others, creating an uneven playing field.
We provide open access to all of our questions to everybody. We have created over 100,000 questions in more
than 20 subcategories with thousands of different patterns and parameters. This makes it virtually
impossible to memorize the questions. Of course, there is a certain advantage to studying the different
types of questions, but this advantage is the same for everybody. Plus, we add new content daily to limit
the possibilities for an individual to memorize the test.
People are nervous / had a bad night / have performance anxiety
People can take the intelligence test as often as desired. If you had a restless night, you can always just
take a test again tomorrow. You can do this until you reach your optimal score. We believe this method leads
to a score that comes closest to your “true intelligence”. Most people reach their optimal score after about
three attempts.
People are not native speakers of the language of the test
Most intelligence tests contain questions that test the verbal reasoning capacities of candidates. Although
we believe that someone’s verbal reasoning capacity can correlate with their intellectual capacity, we have
not included these types of questions in our tests. We believe that verbal reasoning capacities are heavily
influenced by different cultural backgrounds, education, social standing, and other aspects which end up
creating an uneven playing field.
We have tried to limit the amount of text in the questions and used simple language as much as possible. Of
course, people will need a basic understanding of the test language, but not more than that is necessary to
complete a test.
People who take the test are not random/average
In order to calculate the individual IQ scores, the results of the intelligence tests are made by comparing
all of the test scores of everybody who has ever taken the test on BRGHT. It is reasonable to assume that
people who believe they will achieve good results are more likely to take the test than those who believe
they will not see good results.
Therefore, it is reasonable to assume that the population we use to calculate the intelligence score is not
random. However, we have chosen to not make artificial changes to the score. In order to calculate the
percentile score and the intelligence score, an individual “raw score” is compared to all other raw scores.
This way, everybody can clearly see what their own scores mean and all scores can be compared to each other.
Comparing your own IQ score to those of other people, whose IQ scores are based on our tests, is very
accurate. However, comparing your score to other IQ scores that are based on other tests might be less
accurate.