Master Jane Street's unique interview process with our comprehensive collection of real interview questions, probability problems, market making scenarios, and mental math challenges. Get hired at one of the world's most prestigious trading firms.
Fast arithmetic, fractions, percentages, and numerical reasoning under time pressure.
Complex probability problems, conditional probability, and statistical reasoning.
ETF arbitrage, bid-ask spreads, risk management, and market dynamics.
Brain teasers, optimization problems, and analytical reasoning challenges.
Real-world trading situations, market analysis, and strategy development.
Cultural fit, motivation, teamwork, and communication skills assessment.
You flip a fair coin until you get two consecutive heads. What's the expected number of flips?
Use Markov chains or recursive expectation. Let E be the expected number of flips. Consider the states: start (0), one head (1), two heads (2).
E = 6 flips. This is a classic problem that tests your understanding of expectation and recursive thinking.
An ETF is trading at $102, but its NAV is $100. The creation/redemption fee is $0.50. What arbitrage opportunity exists and how would you execute it?
Calculate the net profit after fees. Consider the ETF is trading above NAV, so you want to create shares and sell them.
Net profit = $102 - $100 - $0.50 = $1.50 per share. Create ETF shares at NAV ($100), pay creation fee ($0.50), sell at market price ($102).
You have 12 coins, one of which is counterfeit (heavier or lighter). Using only a balance scale, find the counterfeit coin in exactly 3 weighings.
Divide coins into groups and use the balance scale strategically. Each weighing can eliminate 2/3 of possibilities.
First weighing: 4 vs 4 coins. Second weighing depends on result. Third weighing identifies the exact counterfeit coin.
Jane Street typically has 3-4 rounds: initial phone screen, technical interviews, and final round with senior traders. Each round focuses on different aspects of quantitative reasoning and cultural fit.
Communication and collaborative problem-solving are most important. Jane Street values candidates who can work well in teams, explain their reasoning clearly, and approach problems systematically.
Focus on probability, statistics, mental math, and market making concepts. Practice explaining your thought process out loud. Study ETF mechanics and arbitrage strategies. Prepare for 2-3 months with daily practice.