What Is the WAIS? The Difference Between Formal IQ Tests and Free Online Tests

Plenty of people wonder "what exactly is the WAIS?" and "how do formal IQ tests differ from free online ones?" In this article we lay out the main types of IQ tests and give an honest account of where an online test like BrainRank fits in.

What Is the WAIS?

The WAIS (Wechsler Adult Intelligence Scale) is a leading IQ test for adults, administered one-on-one by professionals such as psychologists. It measures several indices in detail—verbal comprehension, perceptual reasoning, working memory, and processing speed—so it captures not just an overall IQ but also a profile of abilities (the pattern of one's strengths and weaknesses).

For children there is the WISC, the children's version in the same Wechsler family, with the two used according to age.

The Difference From the Binet Scales (Stanford-Binet)

Another leading test is the Stanford-Binet scale. Historically descended from the earliest IQ tests, it too is administered by trained examiners following standardized procedures. Both the WAIS and the Binet scales express results on a normal distribution scaled to a mean of 100 and a standard deviation of 15, which is the modern standard. For the basics of how to read a score, see our explanation of the average and distribution of IQ as well.

The Difference From Free Online Tests

A free test like BrainRank is a screening tool (a rough guide) that you can take easily at home. The questions focus mainly on nonverbal reasoning tasks such as figures, patterns, and logic, with no observation or interview by a professional. For this reason the result is only an estimate, different in nature from the clinical diagnosis produced by a formal test like the WAIS. How BrainRank calculates its estimated IQ is published on our methodology page.

Which Should You Choose?

If you want to connect to a diagnosis or support—for example, with developmental or learning difficulties—a formal assessment at a medical or specialist institution is necessary. On the other hand, if your goal is simply to get a casual sense of your own reasoning tendencies or a rough idea of where you stand, an online estimate is plenty useful. On a normal distribution, for instance, IQ 130 places you in roughly the top 2% (about 1 in 50 people), and an online test is well suited to grasping this kind of relative positioning. You can review the benchmarks for each score together in the IQ quick reference table.

What matters is using each tool for its purpose. If you'd like to try one casually first, check your estimated score and top-percentage standing with the free IQ test.