Free IQ Test —
Adaptive Cognitive Assessment
40–50 adaptive questions across 6 cognitive domains. Powered by Item Response Theory for clinically meaningful accuracy. Get your IQ score, percentile, and full cognitive profile — completely free.
How it works
Select your age group
Age-adjusted norms ensure your score is compared fairly to peers in your demographic.
Answer adaptive questions
The test adapts in real time. Each question is chosen to maximise scoring accuracy at your current estimated ability.
Get your cognitive profile
Receive your IQ score, percentile, confidence interval, and a breakdown across all six cognitive domains.
Six cognitive domains measured
Fluid Reasoning
Solve novel problems without prior knowledge. Pattern detection and logical deduction.
Quantitative Reasoning
Number series, arithmetic patterns, and mathematical logic under timed conditions.
Crystallized Intelligence
Verbal analogies, word relationships, and knowledge accumulated through experience.
Spatial Reasoning
Mentally rotate and manipulate 3-D objects. Visualise shapes and transformations.
Working Memory
Hold and manipulate sequences of digits and symbols in short-term memory.
Processing Speed
Quickly and accurately complete simple cognitive tasks. Reaction time and mental agility.
IQ classification bands
IQ is normally distributed with mean 100 and standard deviation 15 (Wechsler scale).
What you receive after completing the test
Your composite IQ on the Wechsler scale (mean 100, SD 15)
Where you stand relative to the general population
95% confidence band (±5 points) around your score
Your IQ band label (Average, High Average, Superior, etc.)
Visual breakdown of all 6 cognitive domains
Personalised interpretation of each domain score
Printable 4-page professional assessment report
Track your cognitive profile over multiple attempts
Methodology
Adaptive testing (CAT). Questions are selected in real time using Fisher Information maximisation over a 3-Parameter Logistic IRT model. Each question is the most discriminating one possible at your current estimated ability level.
Age-adjusted norms. Scores are normalised against population data for your age group (18–24, 25–34, 35–44, 45–54, 55–64, 65+). This accounts for known lifespan differences in fluid vs crystallised intelligence.
Validity checks. Every session is screened for speed-clicking, chance responding, focus loss, and internal inconsistency. Invalid sessions are flagged rather than scored to preserve result integrity.
Self-assessment scope. This is a self-administered psychometric tool for personal insight. It is not a clinical diagnosis. If you have concerns about cognitive health, consult a qualified psychologist.
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Frequently asked questions
How is this different from other free IQ tests?+
Most free IQ tests use fixed question sets and simple percentage scoring. This test uses Computerized Adaptive Testing (CAT) with Item Response Theory — the same technique used by major standardised assessments like the GRE and GMAT — so every question is chosen to be maximally informative for your specific ability level.
Can I retake the test?+
Yes, but a 24-hour cooldown applies between attempts. This prevents score inflation from repeated practice and preserves the validity of your result.
Should I prepare for the test?+
No. The test is designed to measure natural cognitive ability, not acquired knowledge. Cramming IQ-style questions can temporarily inflate scores without reflecting genuine ability. Take it rested and without distractions for the most accurate result.
Is my data private?+
Anonymous sessions are fully supported — no account required. If you take the test without signing in, no personally identifiable data is stored beyond a hashed session token. IP addresses are hashed before storage.
What is a good IQ score?+
The average IQ is 100 by definition. Scores between 90–110 are within the "Average" range and describe about 50% of the population. A score of 120+ is "Superior" (top ~9%), and 130+ is "Very Superior" (top ~2%).
Ready to find out your IQ?
Takes 25–40 minutes. No sign-up required. Your score is shown immediately.
Start Free IQ Test