Free IQ Test — Brief Psychometric Cognitive Screening
Manhattan Cognitive Assessment (MaCA)
A free, twelve-minute cognitive screening built by a clinical psychologist. Eight psychometric subtests across four CHC-mapped domain indices yield a Composite Cognitive Index (CCI) with an embedded performance-validity check.
Live tasks available now: Verbal Analogies · General Knowledge · Abstract Pattern Reasoning · FCRM (Recognition Memory) · Color Stroop · Lexical Decision · Mental Rotation
Eight Subtests — CHC Classification
| Subtest | Domain | CHC Stratum | What It Measures | Status |
|---|---|---|---|---|
| Lexical Decision (LDT) | VLI | Gc — Verbal / Semantic | Lexical-semantic retrieval speed; RT against ELP norms | ✓ Live |
| Verbal Analogies | VLI | Gc / Gf Bridge | Semantic relationship reasoning over stored knowledge | ✓ Live |
| General Knowledge | VLI | Gc — Crystallized | Declarative world knowledge; g-loaded, neurologically resilient | ✓ Live |
| Abstract Pattern Reasoning (APR) | NVI | Gf — Fluid Reasoning | Matrix completion on novel figural material; most culture-reduced | ✓ Live |
| Mental Rotation | NVI | Gv — Visuospatial | 3D object rotation; RT scales linearly with angular disparity | ✓ Live |
| FCRM-1 (Immediate Recognition) | MLI | Glr — Encoding + Validity | Forced-choice recognition; primary performance validity indicator | ✓ Live |
| FCRM-2 (Delayed Recognition) | MLI | Glr — Consolidation + Validity | Delayed forced-choice; dissociates encoding from consolidation failure | ✓ Live |
| Color Stroop | EFI | Gs — Executive Attention | Inhibitory control; suppress reading to name ink color | ✓ Live |
Scientific Foundations
The MaCA is built according to Cattell-Horn-Carroll (CHC) theory — the most empirically supported framework for ability structure. Each subtest maps to a narrow ability within a broad CHC stratum. The Composite Cognitive Index aggregates across strata to produce a single general cognitive ability estimate.
The embedded forced-choice recognition memory (FCRM) paradigm provides a performance-validity check. Performance substantially below chance-level on an easy forced-choice task — a format designed to be trivially easy for an engaged test-taker — signals non-credible effort and should prompt cautious score interpretation. The validity framework follows Slick, Sherman & Iverson (1999).
All scores are expressed as T-scores (M = 50, SD = 10) and the composite maps onto an IQ-scale metric (M = 100, SD = 15) via a provisional convenience-sample norming study. Results are for research and educational use only.
Learn more: Intelligence, ability vs. achievement, and CHC theory →