James Moriarty IQ: How Smart Is Moriarty?
Fan analysis, for fun · Last reviewed September 2026
James Moriarty's IQ is estimated at 165 to 185.
Moriarty is a mathematical prodigy who wrote a celebrated treatise on the binomial theorem at 21, then built a hidden criminal organisation that only Sherlock Holmes could see.
This is a fan analysis for fun. James Moriarty is fictional, so nobody has taken a real IQ test. The range reflects what the character actually does in the story.
- Estimated IQ
- 165 to 185
- Thinking style
- Systemic and hidden
- Known for
- Being Sherlock Holmes's greatest enemy
- Source
- Arthur Conan Doyle stories, plus BBC Sherlock (2010 to 2017)
Who is James Moriarty?
Professor James Moriarty appears in very few of Arthur Conan Doyle's stories, yet he is the most famous villain in detective fiction. In The Final Problem, Holmes describes him as the Napoleon of crime: a brilliant academic sitting at the centre of a web of criminals.
Most of this page uses the original stories. The BBC version with Andrew Scott is noted separately.
The evidence: how smart is Moriarty?
- 1
A mathematical prodigy
Holmes explains that Moriarty wrote a treatise on the binomial theorem at 21 that won him a European reputation and a chair of mathematics. In The Valley of Fear, he is also the author of The Dynamics of an Asteroid, a work so advanced that, Holmes says, no one could criticise it.
- 2
The invisible organisation
In The Final Problem, Holmes tells Watson that Moriarty organises half the crime in London while never being involved directly. He plans, his agents act, and nothing leads back to him. Holmes spends months breaking the network, and Moriarty realises it, which is why he comes after Holmes personally.
- 3
The BBC heist
In BBC Sherlock's The Reichenbach Fall, Jim Moriarty breaks into the Tower of London, the Bank of England and Pentonville Prison at the same time, then lets himself be caught. It is a show of power designed to make the world doubt Sherlock. The adaptation is bolder than the canon, but true to the idea of Moriarty as Holmes's mirror.
How Moriarty thinks
Thinking style
Systemic and hidden
Moriarty thinks like a mathematician running an organisation. He designs structures that work without him being present, protects himself with layers of agents and plans crimes the way others solve equations.
Three strengths
Mathematical genius
His published work made him famous in academic circles before crime did.
Building networks
He runs a criminal organisation that the police do not even know exists.
Invisibility
Nothing he does can be traced back to him, until Holmes starts pulling threads.
Two blind spots
Personal vendetta
When Holmes damages his network, Moriarty makes it personal, which draws him out into the open at the Reichenbach Falls.
Pride
He meets Holmes face to face to warn him off. A truly careful villain would not have.
James Moriarty's personality type
MBTI type (fan consensus)
INTJ
The original Moriarty is usually typed INTJ by fans, for his cold, systematic planning. The BBC version is often typed ENTP because of his theatrical, chaotic energy.
Big Five profile
- OpennessHigh
- ConscientiousnessVery high
- ExtraversionLow
- AgreeablenessVery low
- NeuroticismLow
Canon Moriarty is controlled, organised and reserved, with no visible warmth. The BBC Moriarty is far more extraverted and unstable, which is one reason fans type the two versions differently.
Curious how your own Big Five compares with Moriarty's? Take the free personality test.
Moriarty vs Sherlock Holmes, Hannibal Lecter and Lex Luthor
| Character | Estimated IQ | Thinking style |
|---|---|---|
| James Moriarty | 165 to 185 | Systemic and hidden |
| Sherlock Holmes | 160 to 180 | Deductive, physical clues |
| Hannibal Lecter | 170 to 190 | Psychological, aesthetic |
| Lex Luthor | 170 to 180 | Corporate, resource-driven |
- Moriarty vs Sherlock Holmes: Holmes himself treats Moriarty as his intellectual equal. They are two versions of the same mind.
- Moriarty vs Hannibal Lecter: Lecter kills personally and elegantly. Moriarty never touches the crime.
- Moriarty vs Lex Luthor: Both are genius villains obsessed with one hero. Luthor has a company; Moriarty has a web.
Real genius comparison
Moriarty vs Pythagoras
Pythagoras was a mathematician who also led a secretive brotherhood with its own rules. A maths genius at the centre of a hidden network is exactly the picture Doyle paints of Moriarty.
Pythagoras's estimated IQ is 155+, a historical estimate from biographical records, not a test score.
Read Pythagoras's IQ profileHow we estimate fictional IQs
We look at what the character actually does: problems solved, plans that work, how fast they learn and how they compare with other brilliant characters in the same story. The range is a fan estimate, not a measurement.
Even the low end of the range, 165, would score higher than about 99.999% of people, roughly 1 in 136,074. Real tests become much less reliable this far above average.
Based on Doyle's The Final Problem and The Valley of Fear, with BBC Sherlock noted separately.
James Moriarty IQ: common questions
What is James Moriarty's IQ?+
James Moriarty's IQ is estimated at 165 to 185. Moriarty is a mathematical prodigy who wrote a celebrated treatise on the binomial theorem at 21, then built a hidden criminal organisation that only Sherlock Holmes could see. It is a fan estimate for fun, based on what Moriarty does in the story.
What is James Moriarty's MBTI personality type?+
James Moriarty is most commonly typed INTJ by fans. The original Moriarty is usually typed INTJ by fans, for his cold, systematic planning. The BBC version is often typed ENTP because of his theatrical, chaotic energy.
Is Moriarty smarter than Sherlock Holmes?+
Holmes himself treats Moriarty as his intellectual equal. They are two versions of the same mind.
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