I applied online. I interviewed at Jane Street (London, England) in Nov 2025
Interview
Online interview, around 30 minutes. Asked some probability-based maths questions. Had to do some algebra and find the best strategy for the game that they had proposed. Also asked for initial thoughts before actually getting into any maths.
Interview questions [1]
Question 1
Game about a bag containing different coloured marbles with different values. Asked about optimal strategy to make the most money.
There was a few phone interviews that involved probability and game theory questions. Before a final round interview in hong kong. Interviewers are very nice best to describe your thought process
Interview questions [1]
Question 1
They asked me probability and gamer theory questions.
Interviewed for two rounds. I passed the first round last year so was able to continue immediately with the second this year. Probability/game theory questions. The interviewers are friendly and helpful.
Interview questions [1]
Question 1
If you roll a dice and receive that amount in dollars but have the option of rerolling up to two times, how much would you like to pay to play this game?
Jane Street’s interview process is fast-paced, multi-round (But if you have a deadline they will react accordingly) , and deeply quantitative: mental math, probability puzzles, game theory..., and conversational talk just before you start doing the problems
Interview questions [1]
Question 1
Some basic probability questions (more like brainteasers) involving expected values and markov chains. You should brush up on the greenbook and be comfortable with n-sided dice and strategies involving dice in general.