Sep 9, 2025·Advanced Topics & Research

IQ Test Quality

Find out what makes an IQ test reliable, why professional design matters, the role of norm samples, and how to spot legitimate online tests like the RIOT.

Dr. Russell T. WarneChief Scientist

There are many online tests that claim to measure IQ, but unfortunately very few online tests are high-quality tests created by professionals. Before taking an online IQ test, it is important to do some research before spending time or money to take an IQ test.

Are Online IQ Tests Reliable?

The fact that a psychological test is offered online is not, by itself, evidence of the quality of the test. The internet makes psychological testing available to a wide audience and greatly reduces the costs of professional assessments. Unfortunately, it also provides non-professionals an avenue for creating shoddy tests that can deceive the public. The quality of online tests ranges from tests on par with traditional tests administered face-to-face (like the Reasoning and Intelligence Online Test), to tests that are designed by scammers to take money from trusting examinees. In between there is a lot of grey area, including tests created by psychologists for research purposes, tests created by well-meaning amateurs, and tests created to mimic professional tests. A few minutes of basic research can help customers protect themselves from wasting their time and money.

Professionally Created IQ Tests - The #1 Goal

Psychological tests are scientific instruments that are sometimes used to make important decisions about people’s lives. Only an expert professional can create a test that produces the quality of data expected of a scientific instrument. Amateurs should not be entrusted with this task, just as they would not be entrusted to create a medical test designed to make decisions about people’s physical health. Before purchasing an online psychological test, customers should ask themselves, “Would I trust this person with making an important scientific decision?”

Legitimate test creators disclose their identity and their credentials to their customers. Indeed, professional test creators are very proud of their tests and are proud to attach their name to their work. If a customer cannot find the name and background of a test’s creator, they should not take the test.

Professional test creators are bound by ethics codes and technical standards that take years to understand and apply. The most widely used set of standards are established by the American Educational Research Association, the American Psychological Association, and the National Council on Measurement in Education. These organizations do not certify tests or give a stamp of approval, but they do state the expectations that tests should meet before they are administered. There are other ethical or technical standards that may apply, too. Non-professional test creators are unaware of these standards, and this puts examinees at risk, just as when non-professionals try to create or interpret data from medical or scientific tests.

Norm Sample or Comparison Group

High-quality tests will have a “norm sample” that is representative of the population the test is designed for. A test’s norm sample is the group of examinees that future test takers’ scores are compared to in order to determine whether a person scored “above average” or “below average” (and how far from the average a score is). A representative norm sample is essential because comparisons to non-representative groups -- such as the people who seek out and pay to take a test -- are distorted. Legitimate tests have documented norm samples that resemble the target population of the test’s examinees.

Free Valid IQ Tests

There are a limited number of online free IQ tests created by professionals. Most of these tests are designed for research purposes, and caution should be exercised when using the scores for non-research purposes. Some tests also provide an abbreviated free version, such as the Sample version of the Reasoning and Intelligence Online Test (RIOT). These can be useful for providing a preview of the test or to prepare examinees for a full-length test.

Most free online IQ tests, though, are not legitimate scientific instruments. Test development is expensive, and this means that professional test creators need to charge money to pay for their upfront costs. However, online testing is still much less expensive than traditional psychological tests administered face-to-face. The costs of a legitimate IQ test like the RIOT are worth it because the examinees are paying for more than an IQ score. They are paying for technical expertise, scientific integrity, and peace of mind.