What an online IQ test can and cannot tell you, and how clinical tests such as the WAIS differ.
The Wechsler Adult Intelligence Scale, now Pearson's WAIS-5 from 2024, is a one-to-one clinical IQ test. What changed from the WAIS-IV, what it costs, and why a free online WAIS quiz is not the real test.
The Stanford-Binet Intelligence Scales, Fifth Edition (Roid, 2003) is a one-to-one clinical IQ test with 10 subtests and five factors (PRO-ED). How it is given and scored, and why online quizzes differ.
Calculated from the WAIS-5's 0.97 reliability (2024), a clinical IQ score has a 95% range of about 5 points either side. Online tests vary, and most free quizzes publish no data.
24 puzzles, about 15 minutes, a short warm-up first.
