Free quant interview questions
168 of the 1,260 questions on QuantGauntlet, free to read, with full solutions. They cover probability, EV, Bayes, market making, stats, options and the coding topics that come up in quant dev rounds. All of them are original. Sign in if you want to answer them with hints and track how you're doing.
Quant trading
Expected value & odds
Price uncertain payoffs and account for all costs.
Information & Bayes
Update the model when you observe a signal or an order.
Counting & stopping
Count outcomes, use indicators, and reason about waiting times.
Markets & quotes
Connect fair value, spread, inventory, and adverse selection.
Sizing & risk
Separate edge from position size and understand aggregation.
Options & hedging
Build intuition for payoff, parity, delta, and convexity.
Execution & microstructure
Reason about fills, fees, benchmarks, and queue position.
Numerical judgment
Calculate quickly while keeping scale and units straight.
Option pricing models
Binomial trees, Greeks, the volatility smile and parity arbitrage.
Quant research
Probability & inference
Connect sampling variation, likelihood, and uncertainty.
Regression & linear algebra
Understand what the fitted coefficients can and cannot mean.
Machine learning judgment
Choose evaluation, regularization, and metrics deliberately.
Time-series reasoning
Respect dependence, temporal ordering, and forecast horizons.
Backtest integrity
Audit the information clock and the experiment boundary.
Portfolio & factor risk
Translate forecasts into exposures and risk-aware comparisons.
Data & feature research
Audit joins, missingness, vintages, and label construction.
Research decisions
Design tests that can distinguish a real improvement from noise.
Take-home data cases
Small tables with the traps real take-homes hide: duplicates, splits, survivorship, look-ahead and units.
Stochastic calculus & linear algebra
Brownian motion, Itô’s lemma, quadratic variation, eigenvalues, projections and factorizations.
Quant development
Python correctness
Trace state, references, iteration, and collection behavior.
Algorithms & structures
Pick a structure by its operations and constraints.
C++ ownership & memory
Reason about lifetimes, ownership, and invalidation.
Concurrency & coordination
Protect invariants, not just individual instructions.
Networking & latency
Handle transport semantics, retries, and tail behavior.
Streaming market data
Update aggregates and rebuild books without losing the invariant.
SQL & data pipelines
Understand cardinality, window functions, and deterministic ordering.
Numerics & testing
Test precision, boundary cases, and mathematical invariants.
Trading system components
Order books, matching engines, caches, rate limiters, ring buffers and feed handlers.