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Optiver interview questions and how to prepare

29 problems · 7 min read · updated 2026-09-07

Optiver’s process is the most explicitly timed of the major market makers. It opens with an arithmetic test — dozens of questions in a handful of minutes — and everything after it keeps that tempo: dice expectations you should know cold, markets you must quote in seconds, options questions where the interviewer wants the sign of a Greek before the formula.

This guide is organised around that tempo. Speed sections first, then the market-making and options rounds where the interview is actually won.

Mental math and speed

The arithmetic screen is pass/fail and most candidates who fail Optiver fail here. Beyond raw arithmetic, the questions below are the ones a trader is expected to answer without paper: quick approximations, small expectations, and one-line probabilities.

Approximate cos(0.1)

EasyJane StreetOptiver

Using the Taylor expansion cosx1x2/2\cos x \approx 1 - x^2/2, approximate cos(0.1)\cos(0.1). (Round to 3 decimals.)

Answer: 0.995 · Worked solution →

Ants on a Triangle

MediumGoldman SachsOptiver

Three ants sit on the three corners of a triangle. Each independently picks one of the two edges and starts walking. What is the probability that none collide?

Answer: 1/4 · Worked solution →

Two Dice Sum to 7

EasyOptiverIMC Trading

Two fair six-sided dice are rolled. What is the probability their sum equals 7?

Answer: 1/6 · Worked solution →

At Least One Six

EasySIG / SusquehannaOptiver

You roll a fair die 4 times. What is the probability of getting at least one 6? (Round to 3 decimals.)

Answer: 0.518 · Worked solution →

Expected Rolls for a Six

EasyOptiverIMC Trading

What is the expected number of rolls of a fair die to get the first 6?

Answer: 6 · Worked solution →

Flips Until First Head

EasyOptiverIMC Trading

What is the expected number of flips of a fair coin until the first head appears?

Answer: 2 · Worked solution →

Expected value and dice

Optiver loves dice because they make expected value concrete and fast. Expected max and min of two dice, Galileo’s three dice, the broken stick — know these cold, and know how to re-derive them when the die is loaded.

Expected Max of Two Dice

MediumOptiverIMC Trading

Two fair six-sided dice are rolled. What is the expected value of the larger of the two (ties count as that value)?

Answer: 4.472 · Worked solution →

Expected Min of Two Dice

MediumOptiverSIG / Susquehanna

Two fair dice are rolled. What is the expected value of the smaller of the two (ties count as that value)?

Answer: 91/36 · Worked solution →

Galileo’s Three Dice

MediumOptiverIMC Trading

Three fair dice are rolled. Gamblers noticed sums of 10 appear more often than sums of 9, though both can be written as 6 unordered combinations. What is the probability of rolling a sum of exactly 10?

Answer: 0.125 · Worked solution →

The Shorter Piece

MediumOptiverMorgan Stanley

A stick of length 1 is broken at a point chosen uniformly at random. What is the expected length of the shorter piece?

Answer: 0.25 · Worked solution →

Top Two Aces

MediumSIG / SusquehannaOptiver

A standard 52-card deck is shuffled. What is the probability the top two cards are both aces? (Enter as a fraction or decimal.)

Answer: 1/221 · Worked solution →

Market making

Quote a fair value, quote a spread, get traded against, manage the inventory you end up with. Fermi questions appear here too — Optiver uses estimation markets ("make me a market on the number of piano tuners in Chicago") to test the same quoting reflex on a number nobody knows.

Make a Market on Two Dice

EasyOptiverSIG / Susquehanna

An interviewer asks you to make a market on the sum of two fair six-sided dice. Before you quote a bid and an ask, you need the fair value. What is it?

Answer: 7 · Worked solution →

Fair Value of a Loaded Die

MediumOptiverIMC Trading

A die is loaded so that it shows 6 with probability 1/2; the other five faces are equally likely. You must quote a fair value for one roll. What is it?

Answer: 4.5 · Worked solution →

Odds to Probability

EasyFlow TradersOptiver

A betting market quotes decimal odds of 4.0 on an outcome (total payout per $1 staked). Ignoring any bookmaker margin, what probability of the outcome does this quote imply, in percent?

Answer: 25 · Worked solution →

Skewing Off an Inventory

EasyOptiverFlow Traders

You are a market maker and have accumulated a long position of 5,000 shares that you want to reduce. Fair value is unchanged. Relative to your previous quotes, in which direction do you move your bid and ask — up or down?

Worked solution →

Piano Tuners in Chicago

EasyOptiverIMC Trading

Estimate: how many piano tuners work in Chicago? There is no “right” number — the interviewer is grading the structure of your estimate, the reasonableness of each input, and whether the final answer is the right order of magnitude.

Worked solution →

Two-Thirds of the Average

MediumJane StreetOptiver

Everyone in a large group simultaneously picks a number from 0 to 100. The winner is whoever is closest to two-thirds of the group average. If every player is perfectly rational and knows everyone else is too, what number does game theory say everyone picks?

Answer: 0 · Worked solution →

Options intuition

Optiver is an options market maker and the interview shows it. Signs and limits of the Greeks, delta of a forward, why gamma explodes near expiry, what a straddle’s delta is — intuition first, Black-Scholes second.

Delta of an ATM Call

EasyOptiverIMC Trading

Roughly what is the delta of an at-the-money European call on a non-dividend stock with short time to expiry?

Answer: 0.5 · Worked solution →

Delta of a Forward

EasyOptiverIMC Trading

What is the delta of a forward contract on a non-dividend-paying stock (with respect to the spot)?

Answer: 1 · Worked solution →

Gamma Near Expiry

MediumOptiverIMC Trading

As an at-the-money option approaches expiry, what happens to its gamma — and why?

Worked solution →

Sign of Theta

MediumOptiverSIG / Susquehanna

For a long vanilla option with no carry, is theta (sensitivity to the passage of time) typically positive or negative, and why?

Worked solution →

Sign & Peak of Vega

EasyOptiverIMC Trading

Is the vega of a long vanilla option positive or negative, and at what moneyness is it largest?

Worked solution →

Delta Hedging

EasyOptiverCitadel Securities

You are short 100 call options, each with delta 0.4 (each option on 1 share). How many shares do you buy or sell to be delta-neutral?

Answer: 40 · Worked solution →

Delta of an ATM Straddle

MediumOptiverIMC Trading

You buy an at-the-money straddle (one call and one put, same strike and expiry) on a non-dividend stock. Roughly what is the net delta of the position?

Answer: 0 · Worked solution →

Value of a Box Spread

MediumOptiverCitadel Securities

A box spread is built from European options with strikes 90 and 110 expiring in 1 year. With a continuously-compounded risk-free rate of 5%, what is its arbitrage-free value today (in dollars)?

Answer: 19.02 · Worked solution →

Teasers and games

Fewer than Jane Street, but present: backward-induction puzzles and games with a clean expected value.

Screwy Pirates

HardJane StreetOptiver

Five rational pirates split 100 gold coins. The most senior proposes a split; if at least half (including the proposer) approve, it passes — otherwise he is thrown overboard and the next-senior proposes. Pirates prioritise survival, then gold, then bloodthirst. How many coins does the most senior pirate keep?

Answer: 98 · Worked solution →

Mislabeled Jars

MediumJane StreetOptiver

Three jars are labeled “Apples”, “Oranges”, and “Apples + Oranges”. Every label is wrong. Drawing one fruit at a time without looking, what is the minimum number of draws to correctly relabel all three jars?

Answer: 1 · Worked solution →

How Long Until Ruin or Riches

MediumOptiverSIG / Susquehanna

You start with 30andbet30 and bet 1 on a fair coin each round, stopping when you reach 0or0 or 100. What is the expected number of rounds until you stop?

Answer: 2100 · Worked solution →

Roll, Keep or Re-roll

MediumJane StreetSIG / Susquehanna

You roll a fair die and are paid its face value in dollars, but you may re-roll up to two times, keeping only the final roll. Playing optimally, what is this game worth?

Answer: 4.67 · Worked solution →

How to approach these in the interview

Drill the arithmetic screen separately. Ten minutes a day of timed mental arithmetic for two weeks moves most candidates from failing to passing. Nothing else on this page matters if you do not clear it.

Answer with the sign first. For any Greek or sensitivity, say the direction, then the magnitude, then the formula if asked. Optiver interviewers are traders; they think in signs.

Treat estimation as a market. For Fermi questions, give a range and a midpoint, and update if the interviewer offers a trade. They are testing quoting behaviour, not trivia.

Use the Trader track. It orders the dice, market-making and options problems on this page in the sequence Optiver rounds tend to follow.

Frequently asked

What is on the Optiver math test?

Fast mental arithmetic — addition, subtraction, multiplication, division, fractions and decimals — under a tight clock. Candidates commonly report on the order of 80 questions in 8 minutes with a penalty for wrong answers, though the exact format varies by year and office, so accuracy and knowing when to skip both matter. It is a screen: pass it to reach the interviews.

Does Optiver ask about options in the trader interview?

Yes, and more than most competitors, because it is an options market maker. Expect questions on the sign and behaviour of delta, gamma, theta and vega, delta hedging, and simple spread valuations, with an emphasis on intuition over formulas.

How is Optiver different from Jane Street and SIG?

Optiver is the fastest and most arithmetic-heavy; SIG leans on poker-style decision questions; Jane Street goes deeper on fewer questions with follow-ups. All three share the market-making round.

How much probability does Optiver require?

Undergraduate probability done fast: expected value, conditioning, the standard dice and coin results. Depth of theory matters less than being able to produce a number in seconds and defend it.

Practise these with answer checking and spaced review

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