Average IQ of a Quant Trader: What Jane Street and Other Firms Test

There is no published average IQ for quants or quant traders. None of the four firm pages we read, from Jane Street, IMC, Optiver and SIG, states an IQ requirement; they describe interviews and aptitude assessments instead. The nearest measured evidence is a Finnish study of 87,914 male investors whose army intelligence scores were matched to their trades: the higher scorers showed better stock-picking, market timing and trade execution. But those scores sit on a nine-point stanine scale, not a Wechsler IQ scale, and the investors were not quants. Figures such as "Jane Street's average IQ is 150" trace to no source we could find.

What is the average IQ of a quant trader?

Nobody has measured it. A firm would have to give its staff a norm-referenced intelligence test and publish the results, and none does. What does exist falls into three kinds of evidence, each of which answers a slightly different question.

• What firms say they test: probability, statistics, problem solving, coding, and for some roles mental arithmetic, with no IQ wording on the pages we read
• What research links to trading results: a Finnish conscript IQ study (87,914 investors) and laboratory experiments on fluid intelligence, cognitive reflection and theory of mind
• What applicants to quantitative fields score on the GRE: physical sciences applicants averaged 161.2 on quantitative reasoning against 156.9 for all test takers, a gap of about 0.4 standard deviations

The GRE figure comes from the testing service ETS: 206,004 people took the test between July 2024 and June 2025, with a quantitative mean of 156.9 and a standard deviation of 10.0. Applicants intending a graduate degree in the physical sciences, a group that includes mathematical sciences, physics and computer science, averaged 161.2 (standard deviation 8.2, 31,844 people), engineering applicants 160.1 and business applicants 159.6. That is a self-selected group taking one test. It is not an IQ scale and it is not data on quants; our guide to GRE and LSAT scores to IQ explains why no official conversion exists.

What do Jane Street, IMC, Optiver and SIG actually test?

Jane Street's page for trading interviews describes phone interviews at the start and in-person interviews for the final stage, which may include problem solving, probability and statistics, coding in any language, data analysis and general interests. It says the interviews feel more like a conversation than a quiz and do not require previous knowledge of finance or involve any complicated math. For its Strategy and Product roles it says the online assessment consists of multiple-choice and short-answer questions and typically takes an hour. On its software engineering page it says it does not ask software engineers to do mental math, olympiad questions or logic puzzles, and adds that other jobs at Jane Street do care about mental math and logic puzzles.

IMC says that for most positions it will ask candidates to complete an aptitude assessment at some point, with a few practice questions beforehand. Optiver's recruiting FAQ names an assessment portal and says assessments can be completed only once every eight months. Neither publishes a question count, a time limit or a pass mark. SIG's intern page gives no IQ wording either. The best-known arithmetic test in this field, "80 in 8" (80 questions in 8 minutes, no calculator), is attributed by candidates and prep sites to Optiver, not Jane Street; Optiver has never published its format, and one prep site reports that 2026-27 invitations list different tests.

So the claim that Jane Street "opens with 60 questions in 8 minutes" is not on any Jane Street page we could read. What the firms' own pages support is narrower: numerate, logical, comfortable with probability, and for some roles quick with mental arithmetic.

How do traders do mental math?

By practice and by shortcuts, not by a special gift. Public drills such as Zetamac's Arithmetic Game give two minutes (30 seconds to 10 minutes are also offered) to solve as many addition, subtraction, multiplication and division problems as you can; its page names no author or firm. The shortcuts are ordinary arithmetic, and these three are our own worked examples rather than firm material:

• 47 times 53: treat it as (50 – 3) times (50 + 3), which is 2,500 – 9 = 2,491
• 17 times 24: take 17 times 25 = 425, then subtract one 17 to get 408
• 15% of 240: take 10% (24) and half of that (12), which gives 36

Speed on this kind of task is trainable, which is one reason it is a weak stand-in for IQ. Our guide to what a cognitive ability test at work predicts covers how employers use timed numerical tests and what the score does and does not tell them.

Does IQ predict trading performance?

The strongest data are Finnish. Grinblatt, Keloharju and Linnainmaa (Journal of Financial Economics, 2012) matched conscript intelligence scores, taken at about age 19 or 20, to the trades of 87,914 male investors between 1995 and 2002. The army test has 120 questions on mathematical ability, verbal ability and logical reasoning, and the score is a stanine from 1 to 9. Stanine 9 means at least 1.75 standard deviations above the mean, about 4% of the population, which would be roughly 126 or higher on the IQ scale (our arithmetic). The authors report that high-IQ investors were less subject to the disposition effect, the habit of selling winners too early, and showed better market timing, stock-picking skill and trade execution. An earlier paper by the same authors found that stock market participation rises steadily with IQ.

In laboratory experiments, Corgnet, DeSantis and Porter (Journal of Finance, 2018) studied three factors behind trader performance: fluid intelligence, cognitive reflection and theory of mind. Their abstract says cognitive reflection and theory of mind are complementary, because traders benefit from understanding the quality of signals only if they can process them, and that fluid intelligence provides the computational skills needed to draw a statistical inference. An earlier working-paper version called cognitive reflection the best predictor of a trader's ability to avoid commonly observed behavioural biases. Cognitive reflection is the habit of checking a fast, intuitive answer; our guide to the Cognitive Reflection Test explains how it is scored.

One more finding is often misread. Chevalier and Ellison (Journal of Finance, 1999) found that mutual fund managers who attended higher-SAT undergraduate institutions had systematically higher risk-adjusted excess returns. The measure is the average SAT of the manager's college, not the manager's own score. For how SAT scores relate to IQ, see our guide to SAT score to IQ conversion.

What is Jim Simons' IQ?

No sourced IQ figure for Jim Simons exists in anything we found, so any number is rumour. The same is true of the figures sometimes attached to Renaissance Technologies, Two Sigma or Jane Street staff, usually "north of 140". They read like an HR requirement and trace to none. A cut-off that high would also be odd to set: on the IQ scale 140 is about 1 person in 261, and our guide to how rare a high IQ score is shows how few people sit there.

When brilliant was not enough: Long-Term Capital Management

The industry's starkest counter-example is not about hiring at all. According to the Federal Reserve's history essay, Long-Term Capital Management was founded by former Salomon Brothers vice chairman John Meriwether in February 1994 and led by a team of market experts that included two Nobel laureates. By the end of 1997 it held about $30 in debt for every $1 of capital, and it lost 44% of its value in August 1998 alone. On 23 September 1998 fourteen banks and brokerage firms invested $3.6 billion to rescue it. The Fed brought them together and oversaw the refinancing, but, in its words, it did not put its own funds at risk.

That is the honest ceiling on everything above. Fluid reasoning, fast probability calculation and elite credentials all measurably help, and none is a guarantee. The research on cognitive reflection points at why: raw processing power without the discipline to catch a confident wrong answer is the failure mode LTCM showed at the largest scale.

What this means if you are preparing for one of these interviews

Read the firm's own page first, because the format differs by role: Jane Street says its trading interviews do not need finance knowledge, while Optiver and IMC use online assessments. Drill mental arithmetic if the role asks for it, practise probability out loud so an interviewer can follow your reasoning, and expect timed tests. If you want to see how a raw score on a timed test maps onto a familiar IQ scale, our Wonderlic-to-IQ conversion piece works through the same kind of scale translation, and our own score converter handles the arithmetic for a specific number.

The honest answer to "what IQ do quant firms look for" is that they are not measuring IQ at all, or at least not saying so. They are testing numeracy, probabilistic reasoning, speed where a role needs it, and the discipline to override a wrong first instinct. The firms do not publish a number, and neither should anyone who says they know it.

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