100% FREE · MOST ACCURATE
This accurate IQ test is our full 40 question assessment with ten questions per cognitive domain, a 28-minute timer, and the most precise score we offer. with an accuracy margin of about ±7 points.
What to expect
| DETAIL | THIS TEST |
|---|---|
| Questions | 40 (10 per domain) |
| Time | ~25 minutes (28-minute timer) |
| Accuracy | ±7 points. our best |
| Results | Score, percentile, domains, review, certificate |
| Cost | Free. no sign-up, no email |
Why longer is more accurate
Every question is a small sample of your reasoning ability. More questions mean more samples, which means the random noise of lucky guesses and momentary lapses averages out. That's why the 40-question assessment (±7) beats the 20-question test (±9) and the 10-question test (±12).
Ready to find out your real IQ?
Forty questions, twenty-five minutes. instant results, free certificate, no sign-up.
Start the 40-Question Test →Common questions
Is the 40-question IQ test really free?
Yes. Everything. score, percentile, breakdown, review, certificate. is free. No account, no email, no payment.
Do I have to finish all 40 questions?
If the timer runs out, your answered questions are still scored. But for the full ±7-point accuracy, try to answer them all.
Is this a clinically valid IQ test?
It uses established task types and the standard IQ scale (mean 100, SD 15), but it is a screening estimate. not a clinical instrument. For a validated result, see a licensed psychologist.