How to tell if an online IQ test is reliable
An online IQ test is reliable when it says who you are compared with, shows the margin of error and has enough questions to measure. If it gives an exact number after a few questions, or puts almost everyone above 130, be suspicious.
In this article
Which signs show an online test is serious?
No online test replaces one given by a psychologist, but some are far more honest than others. Six signs help tell them apart:
- It says up front how many questions there are and how long it takes.
- It explains the norm: who your result is compared with, and whether the comparison is by age.
- It shows the margin of error as a range, not just a number.
- It explains the scoring method on a page anyone can read.
- It says what the test is not: that it is not for school, hiring or health decisions.
- It shows what it costs and whether the charge repeats before asking for any payment.
Which signs point to an unreliable result?
The first is math that does not add up. On the normal curve, only about 2 in 100 people score above 130, and about 4 in 1,000 score above 140. A site that hands these numbers to many people has a method problem, such as questions that are too easy or a poorly built norm. The math is in What each score means.
Other signs: an exact number after 10 or 15 questions with no margin; a result that is ready before you finish; and praise during the test that does not depend on your answers. Why few questions measure poorly is explained in Why 40 questions, not 10 or 150.
User percentile or population percentile?
A percentile can compare you with the population, using the theoretical curve, or with the people who took that test on the site. Both are legitimate, but they say different things. People who look for IQ tests online are not a sample of the population, so a ranking of users does not tell you where you would stand among people in general.
A serious site says which one it uses. If it does not, you do not know what the number means.
How does IQNorth measure up to these signs?
This page belongs to IQNorth, so we apply the list to ourselves. We say up front that there are 40 questions and that it takes about 20 minutes. We compare you with the population curve for your age group, using the theoretical percentile, and we show a 95% range. The scoring method is in Method, and the limits of use appear next to the result.
There is also something not finished yet: our norm is provisional, because it is still being adjusted with more data. The reason is in Reasoning and age: what changes and what stays.
See also: Free or paid IQ test: what changes?
Sources
- Condon, D. M., & Revelle, W. (2014). The International Cognitive Ability Resource: Development and initial validation of a public-domain measure. Intelligence, 43, 52–64.
- AERA, APA & NCME (2014). Standards for Educational and Psychological Testing. Washington, DC: American Educational Research Association.
