I applied through college or university. The process took 5 weeks. I interviewed at Jane Street (London, England) in Dec 2024
Interview
You first do three technical zoom interviews, each one progressively more difficult than the previous and more open ended. If these go well you get invited to an onsite interview where the number of interviews vary from 3-5. With these you need to make bets on your answer where not only do you have to calculate whether or not your answer might be reasonable, but also how much risk you're willing to take on your answers, these must also be calculated properly.
Interview questions [1]
Question 1
Some card game problems, dice roll problems, coin toss problems. Not your classical problems though, much more casino-like, but far more convoluted with not enough of time to solve them analytically on the spot (you are not expected to solve them completely, only give approximate solutions).
1st round--45 minute phone call purely technical with brainteasers. no behavorial besides brief introduction of self. i believe there are 2nd and 3rd round phone and a final superday but didn't make it past there.
multiple online interviews, technical in nature, followed by an in person in office interview which lasted an entire day and had multiple stations. focused on problem solving, probablity, game theory etc etc
I applied online. The process took 1 week. I interviewed at Jane Street (London, England) in Nov 2025
Interview
They started with a basic introductory question followed by some probability based stuff. Wasn’t too difficult but you have to ace it, they expect perfection. They cut the interview off at exactly 30 minutes, and will provide hints if you need it though it’s not a good sign if you need them.
Interview questions [1]
Question 1
You have 20 cards. 1 is black the rest are red. You keep drawing cards and get $1 for each red, but if you draw the black the game ends and you get nothing. How do you play and what’s the average payout? Now drawing the black card makes your score go negative, but you can continue drawing cards. What’s the strategy and expected payout now?