Question
Are online IQ tests accurate?
Short answer
Some online IQ tests give a reasonable estimate; many are entertainment. None can replace a full test given by a psychologist. A careful online test uses real reasoning items, scores you against a defined scale, shows a confidence range, and is honest that its number is an estimate, not a diagnosis.
Want your own number? The test is 25 visual puzzles, about 12 minutes, no sign-up.
What even a clinical test cannot do
Start with the gold standard. A full clinical IQ test, given one to one by a trained examiner, still carries measurement error. Its manual reports a confidence interval, often around plus or minus 5 points at 95%, rather than one exact number (Wechsler, 2008). An online test, taken unsupervised on whatever screen you have, cannot be more precise than that. Its range will be wider.
Signs of a careful online test
- Real reasoning items. Matrix puzzles, sequences and number series, the kind used in established nonverbal tests such as Raven's Progressive Matrices (Wikipedia: Raven's Progressive Matrices), rather than trivia.
- A stated method. It tells you how answers become a score and which scale the score is on.
- A range, not just a number. Honest tests show uncertainty.
- Clear limits. It says plainly that it is not a diagnosis and cannot be used for admission to Mensa (Mensa International), schools or jobs.
Try one · Quantitative Reasoning
Which number comes next?
11, 12, 15, 20, 27, ?
Tap the option you think is right, or show the answer.
Show the answer
The next number is 36 (option 4).
How to solve it
- Find the gaps between neighbors: 1, 3, 5, 7.
- The gaps between the numbers grow by 2 each time.
- So the next gap is 9, and 27 + 9 = 36.
That was 1 puzzle. The full test has 25.
Warning signs
Every result in the 130s, a score shown before you have answered enough items to estimate anything, a price revealed only at the end, or a subscription hidden in the checkout. Our free vs paid comparison covers what to check.
Where IQ Octopus fits
IQ Octopus gives an estimated IQ from 25 generated visual puzzles, scored with a Rasch model and shown with a confidence range. It is not a clinical instrument. The method page explains exactly how it works, and the guide to how online IQ tests work goes deeper on what separates a careful test from a toy.
Sources
- Wechsler, D. (2008). WAIS-IV Technical and Interpretive Manual. Pearson.
- About us. Mensa International. www.mensa.org/mensa/about-us
- Raven's Progressive Matrices. Wikipedia. en.wikipedia.org/wiki/Raven%27s_Progressive_Matrices