— MBTI & IQ Research
ISTJ IQ — what's the average for The Logistician?
The average reported IQ for ISTJ (The Logistician) across published MBTI cognitive studies sits around 110 — placing the typical ISTJ in the 75th percentile of the general population.
ISTJs score near average to above-average on standardised tests, with particular strength on detail-oriented numeric tasks.
Why ISTJs tend to score where they do
MBTI type is not a measurement of intelligence — it's a personality typology rooted in Jung's cognitive function theory. But certain dominant function patterns correlate with cognitive task performance:
- Introversion — tends to favour deep, sustained processing of abstract material
- Sensing (S) — correlates with strong applied and concrete reasoning, often outperforming N types on numeric and spatial subtests
- Thinking (T) — correlates modestly with logical and matrix reasoning task performance
- Judging (J) — has the weakest individual correlation with IQ; matters more for working style than raw ability
The honest caveat
Average IQ by MBTI type is a statistical tendency, not a rule. The standard deviation within any single type is typically 12-15 IQ points — which means there are ISTJs scoring well above 145 and ISTJs scoring below 90. The type tells you nothing about any individual's actual cognitive ability.
If you want to know YOUR actual IQ rather than the average for your MBTI type, take a properly calibrated test that uses real psychometric scoring (IRT 3PL Bayesian MAP estimation) rather than a quick quiz.
How ISTJ compares to other types
- ESTJ — average IQ 111 (The Executive)
- ISFP — average IQ 109 (The Adventurer)
- ISFJ — average IQ 108 (The Defender)
- ESTP — average IQ 112 (The Entrepreneur)
- ESFP — average IQ 108 (The Entertainer)