Skip to content

Quant Interview Prep

Master the problems
that get you hired.

Practice probability, coding, mental math, market making, Fermi estimation, and firm-specific mock interviews. One structured platform for Jane Street, Citadel, Optiver and more.

No credit card required1335 problemsFree tier forever

Problems from interviews at

Jane StreetCitadelTwo SigmaDE ShawOptiverHRT
1335+Problems
27Topics
110+Free problems
500E·619M·216H
Difficulty

Product tour

A complete training environment for quant interviews

Quant interviews aren't one skill. QuantReady brings together the drills candidates normally piece together from books, coding sites, spreadsheets, and forum posts: problems, speed math, market making, firm-specific guides, and mock interviews.

Problems

Solve probability, coding, finance, and brainteaser problems with a real editor, hidden tests, and step-by-step editorials.

bayes_theorem.pyPython 3
#009EasyProbability

Medical Test: Bayes' Theorem

A test detects a rare disease. Given prevalence, sensitivity and specificity, find P(disease | positive).

Asked at:Jane StreetCitadel
def solve(p, s, c):
    num = p * s
    den = p * s + (1 - p) * (1 - c)
    return num / den
3 / 3 passed·Accepted0.21s
FREE
Start with a free problem

Speed Math

Build the mental fluency fast-paced trading interviews demand: arithmetic, sequences, estimation, probability, and firm-style tests.

Speed Math · Classic Quiz00:28
ProbabilityMixed10 questions30s / question

Question 4 / 10

Expected value of a fair six-sided die?

3.5 
Enter

3 / 3

Correct

100%

Accuracy

8.4s

Avg time

Full accuracy and response-time breakdown in your Performance Stats.

Try a free speed drill

Market Making

Practice expected value, quoting, spread discipline, and risk management through dice, cards, and Fermi estimation games.

Market Making · You Make the MarketRound 3 / 8
?Fair value est. 13.5

Bid

12.8

Ask

14.2

Informed tradersells 10 @ 12.8
Spread1.4
True sum14
P&L +18.0
Play a market making game

Firm Guides

Don't prepare generically. Read firm-specific guides for Jane Street, Citadel, Optiver, HRT, Two Sigma, IMC, and more: what each firm actually tests, the interview format, and which modes to drill, based on public interview reports.

Firm Guides · OptiverInterview guide
Jane StreetCitadelOptiverHRTTwo SigmaIMC

What Optiver tests

Fast mental math (80-in-8)Probability & EVMarket making
Candidate reports describe a fast arithmetic screen (often called 80-in-8), then onsite rounds mixing probability and market-making games. Based on public interview reports.

Recommended prep

  • Speed Math: arithmetic & estimation drills
  • Market Making: dice & quoting games
  • Mock Interview: timed, Optiver-weighted
Explore firm guides

Mock Interview

Simulate a timed, firm-weighted interview drawn from the problem bank, then review a score report with your completion and timing on every problem.

Mock Interview · Score ReportJane Street

75%

Score

3 / 4

Completed

51m

Total time

Problem breakdown

1

Expected Value of a Dice Game

Easy · Probability

Done

6m 12s

2

Optimal Market-Making Spread

Medium · Market Making

Done

14m 03s

3

Card Counting Edge

Medium · Probability

Done

11m 40s

4

Stochastic Process Limit

Hard · Stochastic

Skipped

20m 00s

PREMIUM
See mock interviews

Built for the real interview

Not just another problem bank. Every feature exists because real interviews are hard and preparation needs to match.

Monaco editor, real constraints

The same editor you use at work. Python 3 and C++ — pick C++17, 20, or 23. Time and memory limits, hidden test cases. If your code passes here, it passes on the day.

Company-tagged problem sets

Premium

Problems tagged by firm: Jane Street brain-teasers, Citadel algorithmic sets, Two Sigma probability sequences. Know exactly what to expect.

Structured learning roadmap

Conditional probability before Bayes. Calculus before Black-Scholes. Markov chains before stochastic processes. Each topic shows what to master first, so you stop skipping ahead and getting stuck.

Market making games

Trade against random quotes in dice and card games. Practice expected value estimation, position sizing, and risk management under time pressure.

Speed math training

Arithmetic drills, sequence pattern recognition, and timed quizzes. Sharpen the mental math skills every quant interview demands.

Fermi estimation

Estimate answers to Fermi questions with confidence intervals. Scoring rewards calibration: tight hits earn more, overconfidence is punished.

Where candidates landed

Real outcomes from candidates who prepared with QuantReady. Anonymized at their request.

Hired · Quant Trader, IMC

The market making games were exactly the kind of practice I needed. Being able to drill expected value calculations under time pressure made a real difference in my interviews.

Verified · anonymized

Final round · Citadel

I loved the progression from basic probability problems to stochastic processes. The step-by-step editorials helped me understand not just the answer, but the intuition behind each solution.

PhD Candidate, Applied Mathematics

Verified · anonymized

Offer · Optiver

Coming from a CS background, I needed to quickly ramp up on probability and options pricing. The firm-tagged problems let me focus on exactly what each company asks.

Software Engineer transitioning to Quant

Verified · anonymized

How we compare

Built by quant insiders, for quant candidates.

FeatureQuantReadyCoding sitesPrep books
Probability, brainteasers, options problems
Market making simulation
Mental math & speed drills
Firm-specific prep paths
Prerequisite-aware learning paths
Live code editor & execution
Hidden test cases / auto-grading
Step-by-step interactive editorials
Continuously updated firm content
Full Partial None

Simple pricing, no surprises

Start free. Upgrade when you're ready to go deep.

Free

€0/ forever

Get started with core problems and the full editor.

  • 110+ curated Easy problems across all topics
  • Python 3 & C++ 17/20/23
  • Custom test input
  • Local submission history
Start for free
Most popular

Premium

€34.99/ month

or €275/yr, save 35%

Full access to every problem and feature.

  • All 1,300+ problems (Easy, Medium, Hard)
  • Company-tagged problem sets
  • Advanced topics: Options, Stochastic
  • Full submission history sync
  • Solution editorials
  • Priority support
Get Premium

Your offer is out there.
Start preparing today.

Join candidates who use QuantReady to sharpen their edge before interviews at the world's top quantitative trading firms.

No account required to start. Sign up to save progress.