Jane Street interview prep: no timed OA
Format guide Jane Street's publicly described trading process has no timed mental-math online assessment. Interviews are live probability, expected value, and betting games, worked out loud. This page summarises the process and links to free practice. There is no Jane Street speed test on this site.
The process as publicly described
| Application | Read by a person, with no automated speed-math screen. Most candidates hear back within about a week. |
|---|---|
| Phone interviews | Two or three conversational calls. Pen and paper allowed, no computer or calculator. Most reports describe a linked series of betting and strategy games; some describe hard brainteasers instead. |
| Final round | A full day, office or Zoom: technical interviews with traders (probability, EV, 20-sided-die style sequential games) plus an HR conversation. |
Jane Street publishes its own materials: a mock trading interview video, a walkthrough of the interview format, and a probability and markets PDF. Read those before any third-party guide, this one included.
What interviewers assess
- Reasoning out loud. A wrong turn you explain and then correct scores better than a silent right answer.
- Making a simplifying assumption, trying a smaller case, and checking the edges of a threshold.
- Adapting when the interviewer changes the rules. The die-game variants test how you adjust, so a memorised number does not help.
Free practice on this site
Brain teasers
The first free puzzle is a cycle/permutation problem, a type often cited in Jane Street interview discussions. Cover the answer and talk it through.
Worked puzzlesProbability & EV
Dice, coins, cards, and expected value on a short clock. Drills the arithmetic behind the games; it does not replace playing them with another person.
Daily drillRobot Games
Play or pass a wager against its true EV. Practises the "is this +EV?" check the betting games rely on.
Decision ruleFull prep guide
Pipeline, negative marking at other firms, trading games, and a 5-week plan. Jane Street has no timed OA, but its interviews cover the same ground as other firms' later rounds.
Start hereRelated practice
The full list is on the free tests page.
Questions
Does Jane Street have a timed mental math online assessment?
Not in the trading process described by detailed public guides and by Jane Street's own interview videos. A person reads each application; there is no speed-math screen. Technical interviews are conversational: probability, expected value, and a linked series of betting and strategy games, worked out loud with pen and paper. Some SEO pages claim a 60-question, 8-minute test. The better-sourced write-ups do not support that, so we do not offer one.
What should I practise?
Probability and EV problems, worked out loud with pen and paper under mild time pressure. Accuracy and an argument you can revise count for more than multiplication speed. Jane Street's own probability-and-markets PDF and mock-interview videos are the primary sources. On this site, use the brain teasers, the probability & EV drill, and the Robot Games play/pass drill.
Do I need to be fast at mental maths for Jane Street?
Public guides say this process does not test fast, complex calculation. Numeracy and a feel for magnitudes matter. Optiver-style sprinting at 6 seconds per question is a different exam.
What are the 'three games' on the phone screen?
A commonly reported linked series: a sports-betting or casino game with a chip stack that carries over, a dice game whose rules change, and a divide-and-conquer army/castle allocation game. Scores carry over, so an early loss affects the later games. This is a frequently described pattern; you may not see exactly these three.
Is TradeMind affiliated with Jane Street?
No. This page is an independent summary of the publicly described process. It does not reproduce Jane Street's interview or its games.
TradeMind is an independent training tool and is not affiliated with, endorsed by, or sponsored by Jane Street or any other firm mentioned. This page summarises publicly available descriptions of Jane Street's trading interview process for practice orientation only. Question content linked from this page is procedurally generated or independently rewritten and does not reproduce actual interview material. Formats may evolve.