Short answer: a good online test gives you a ballpark estimate, not an exact or official score. Here is what moves the number, and how to tell a serious test from a sales funnel.
An online test can usually place you in roughly the right range — average, above average, well above average. What it cannot do is pin down an exact score. There is no proctor checking the conditions, no standardized norming sample behind most sites, and your sleep, focus and familiarity with the question types all shift the result. Read any online score as an estimate with a margin of error, not as a measurement like your height.
Different sites use different questions, different numbers of questions, different time limits and different scoring formulas — and some quietly inflate scores, because a flattering result is easier to sell a certificate for. Add your own day-to-day variation on top, and gaps of 10 points or more between two sites are normal. If one site tells you 108 and another tells you 121, neither has necessarily made an arithmetic mistake; they are different rulers.
Any test maker who gives you a single exact number with no range is hiding the uncertainty, not removing it. IQGrab reports every score with a ±6 margin — a score of 100 is best read as roughly 94–106 — and publishes its scoring formula on the homepage before you start, so you can check the math yourself. The test is 30 questions across pattern, number, logic, spatial and verbal reasoning, timed at 20 minutes. That is enough for a reasonable estimate, and the ±6 is there to remind you it is still an estimate.
Be skeptical of a test that hides your result behind a paywall after you have finished, that turns a $0.99 "trial" into a $29.99/month subscription, that explains nothing about how it scores, or that promises an official or certified result online. Those are signs the score exists to sell you something. A serious test tells you the scoring up front, shows its working afterwards, and does not need your email address to hand over a number.
Take the test once, in one sitting, when you are rested. Do not search for answers or get help — that measures the internet, not you. Resist retaking it repeatedly and keeping only your best score; familiarity with the questions inflates later attempts. Then read the result the way it is meant to be read: as a range, next to its percentile. Our IQ score chart shows what each score means in percentile terms.
If a score will be used for anything that matters — a clinical question, school placement, a workplace decision — an online test is the wrong tool. That requires a standardized, proctored assessment such as the WAIS, administered by a licensed psychologist. Online results, including IQGrab's, are for self-assessment and entertainment only, and IQGrab says so on its own report page.
Once you have a number, the IQ score chart translates it into a percentile, and what is a good IQ score? explains how to judge it.
30 questions, 20 minutes, full report with your score, percentile, ±6 range and an explanation for every question. No paywall, no subscription, no email required.
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