Jane Street
4.2 of 5 17 reviews
www.janestreet.com New York, NY 150 to 499 Employees

Jane Street Interview Questions & Reviews

Updated Jul 1, 2014
All Interviews Received Offers

Getting the Interview 

55%
35%
8%

Interview Experience 

55%
31%
12%

Interview Difficulty 

Average Difficulty
418 candidate interviews
Relevance Date Difficulty
in

No Offer

Neutral Experience

Assistant Trader Interview

Assistant Trader

Interviewed at Jane Street

Interview Details – It was a similar process to what others have already described. You have to be ready for the types of questions they will be asking, otherwise you should probably wait on that interview. It's not very hard to get the initial interview, but keep in mind that you'll go through progressively harder interviews.

Interview Question – Similar to what others have stated, make sure you know basic probability, combinatorics, and can do these in your head.   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Neutral Experience

Average Interview

Quantitative Researcher Interview

Quantitative Researcher

I applied online and the process took 6 days - interviewed at Jane Street in June 2014.

Interview Details – Applied online. Got contacted after two days and scheduled an phone interview. Lasted one hour. Asked quickly about my research and programming background. Then shifted to three mathematical problems.
The last two questions seemed designed not to have a simple analytic answer and the interviewer asked to approach one of the problems intuitively and how confident I was about my answers. The interview ended with a few questions I asked about this position at Jane Street.

Interview Question – The last two questions revolved around the following game consisting of drawing two cards from a randomly shuffled deck and repeating the procedure until 2N cards have been drawn. You lose or win one dollar depending on various conditions. Given those conditions, which N gives the highest probability of winning at each step? What if the deck is built by drawing cards from another deck? How much should you get charged if this game is fair?   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Neutral Experience

Average Interview

Trading Interview

Trading

I applied online and the process took 1 week - interviewed at Jane Street in November 2013.

Interview Details – Submitted application for a winter internship through the company site, HR emailed to setup a phone interview a little less than a week later. Interview was purely quantitative, started off relatively easy (mental math, basic probability that you have to answer in 30 or so seconds) and eventually interviewer moved on to more difficult probability questions. You'll be asked to not use your computer/a calculator at all, but the interviewer will walk you through the more difficult problems if you get stuck. Nothing technical/finance related.

Interview Question – Sum the even numbers in the range 1-100.   View Answer

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Positive Experience

Very Difficult Interview

Assistant Trader Interview

Assistant Trader
Princeton, NJ

I applied through college or university and the process took a day - interviewed at Jane Street in February 2014.

Interview Details – Basically, they want to know how much math you're able to do, quickly and efficiently. Knowledge of expected value is a must, as is basic computational skills. You don't necessarily need to be able to think outside of the box, but they're going to want to see exceptional problem solving ability.

Interview Question – You are given a die with 100 sides. One side has 1 dot, one has 2 dots and so on up until 100. You are given a chance to roll the die and, however many dots come up, you can choose to (a): take that many dollars, or (b): pay $1 and roll again. You can continue to reroll as many times as you see fit, but you only keep the money of the one roll that you choose to end with. What is the optimal strategy and expected value?   View Answer

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Neutral Experience

Trader Interview

Trader

I applied online and the process took 3 weeks - interviewed at Jane Street.

Interview Details – Made to the second round (45 min phone interview), the first round is doing probability relate questions online. The second round is also problem solving, but is much harder.

Interview Question – On a multiple-choice exam with three possible answers for each of the five questions, what is the probability that a student would get four or more correct answer just by guessing?   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Neutral Experience

Very Difficult Interview

Junior Trader Interview

Junior Trader

I applied through college or university and the process took 2 weeks - interviewed at Jane Street in January 2014.

Interview Details – Contact was made by e-mail to setup a phone interview. Interview was extremely quantitative, but relatively obscure. Main question was about a complex probability game that the interviewer expected you to calculate mentally. A few more obscure technical questions (as a person coming from a math background) and the interview was over. Process seemed self-defeating as a very small number of people would have the intuition to quickly do a problem like that in their head, but that says little about skill.

Interview Question – As mentioned above, a probability game between two players was given and it involved a complex card game requiring combinatorics.   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

1 person found this helpful

No Offer

Positive Experience

Difficult Interview

Trader Interview

Trader
New York, NY

I applied online and the process took 2 months - interviewed at Jane Street in February 2013.

Interview Details – 4 phone interviews plus 1 on-site final round. I was not impressed with hr as a couple of times they told me I passed the phone interview, that they would schedule the next interview within a week, and then they did not. I had to call them to schedule. Also, they did not call me once for a scheduled interview and had to reschedule.

Phone interviews are mostly math problems / brain teasers. No fit questions whatsoever.

For the final round, they give you a study sheet, and expect you to memorize the jargon inside out. You should be very fluent in their language (of trading). It is pretty difficult, so don't put it off till the last day, and practice. They give you a 100 poker chips and expect you to 'make a market on' various things, such as, sum of the face values of the next four cards flipped, sum of squares of the next two dice rolls, etc. You have limited time, so they expect you to think and ACT fast.

I ended up with ~140 chips at the end. I did not get an offer. I don't think the number of chips matter. I think they evaluate your personality more than anything else. I was not a good fit (I now think I was very risk averse, I only bet when I was very likely to win. That's why I ended up with 140 chips. It's no good though.), so I didn't get the offer. Overall good experience though.

Interview Question – Make a market on the number of numbers in your resume. I sold for 100. There was ~190.   View Answer

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Positive Experience

Difficult Interview

Staff Accountant Interview

Staff Accountant
New York, NY

I applied through a recruiter and the process took 2 weeks - interviewed at Jane Street in April 2014.

Interview Details – Contacted by recruiter, was sent a series of excel tests. Phone screening, followed by face to face. Face to face involved tests and multiple interviews with personnel. Plan on being there all day if you do well on the tests.

Interview Question – "Describe a time when someone you worked with betrayed your trust"   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Positive Experience

Difficult Interview

Trader Intern Interview

Trader Intern

I applied through college or university and the process took 2 weeks - interviewed at Jane Street in April 2014.

Interview Details – Applied in early April, had first interview a week ago, and second interview yesterday. The interviewer for first round was really nice. Gave me some quick mental math (1,000,000 - 111, 12% of 56, etc), and he then gave me a couple probability questions. Second interview was more difficult - one warm up and then one tough question. Prepare to get wrecked.

Interview Question – Expected value of heads and tails of two coin flips -> E(t(10-t) = 10E(t) - E(t^2) = 50 - (25 + 10/4) = 22.5

What is the set of numbers between 2 and 30, without the same common factor (e.g. 26 and 24 share 2, so they cannot be in the same set) that will you give you a max sum?

Using the same rules, what is the highest possible number you can have in a set of 1000?
  View Answers (3)

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response

No Offer

Neutral Experience

Quantitative Researcher Interview

Quantitative Researcher

Interviewed at Jane Street

Interview Details – Submitted resume online and get a phone interview two weeks later

Interview Question – hard mental math   Answer Question

Was this interview helpful?  
Yes | No
Flag Interview  |  Add Employer Response
RSS Feed Embed
Interviews for Top Jobs at Jane Street

Worked for Jane Street? Contribute to the Community!

The difficulty rating is the average interview difficulty rating across all interview candidates.

The interview experience is the percentage of all interview candidates that said their interview experience was positive, neutral, or negative.

Your response will be removed from the review – this cannot be undone.

Glassdoor is your free inside look at Jane Street interview questions and advice. All 418 interview reviews posted anonymously by Jane Street employees and interview candidates.