Optiver Online Assessment: Mental Math, Sequences and Coding

Optiver's trader and research applicants commonly face a sequence of online tests rather than one: the 80 in 8 mental maths test, a number-sequence test, a probability test and a set of short games, ending with a personality questionnaire. Optiver allows one attempt every eight months, so a rushed or interrupted attempt costs most of a recruiting season. This page covers what the Optiver online assessment is, its format and timings, how it is scored, the rules to know before you start, how to prepare and a practice plan.

What the Optiver online assessment is

Optiver is a market maker headquartered in Amsterdam. Its Europe recruitment FAQ does not describe the tests, but it sets the rules around them: assessments can be completed only once every eight months, results from a recent attempt for a similar role are reused, no resets or retakes are offered within eight months once an attempt has started, and the same eight-month wait applies after an unsuccessful application for a similar role. Prep providers describe the trading and research battery as 80 in 8, NumberLogic sequences, Beat the Odds and the Zap-N games, plus the Zap-Q personality questionnaire, with no calculator allowed. Software engineers follow a different track: Optiver describes its engineering interviews as technical discussions rather than standard LeetCode puzzles or brainteasers, in C++, Java or Python.

For the 2026/2027 season, Optiver lists graduate roles for people graduating between October 2023 and October 2027, and internships for penultimate-year students graduating between November 2027 and October 2028. To compare other trading screens, see the SIG online assessment and the Citadel online assessment.

Format and timings

Total: prep providers put the full trading battery at about 2 hours 45 minutes, usually within a three-day window; Optiver does not publish a figure.

How it is scored

• Prep providers report that failing any section ends the process, so each test works as a gate rather than part of an average.
• On 80 in 8, prep providers put the pass mark above 55 and advise aiming for about 70; treat these as reported figures, not official ones.
• Prep providers say Zap-N asks which input device you use and takes it into account, so keep the same mouse or trackpad throughout.
• Optiver says it does not give early-stage feedback because of application volume.

Rules to know before you start

• One attempt every eight months, and no resets once an attempt has started, per Optiver's FAQ.
• Use the link in your original invitation and set up an authenticator app for the one-time login code, as Optiver advises.
• No calculator on the numerical tests, prep providers say; keep paper and a pen for working.
• Optiver aims to contact candidates within seven working days, and reasonable adjustments can be requested at any stage.
• Outside help, including AI tools, is not allowed.

How to prepare

1. Drill 80 in 8 style sets daily: two-digit multiplication, fraction-to-decimal conversion and division to two decimal places, until you clear 70 consistently.
2. Decide your guessing rule in advance: if a skipped answer costs the same point as a wrong one, as prep providers report, there is no benefit in leaving a question blank.
3. For sequences, check differences, ratios, alternating patterns, squares and primes, in that order.
4. For Beat the Odds, revise conditional probability, expected value and simple combinatorics with dice and cards.
5. Software engineers: revise data structures and complexity, memory representation, concurrency and networking, and practice explaining design choices aloud, as Optiver's own tips describe.

A practice plan

1. Day 1: read the invitation for which tests are included, the deadline window and whether a calculator is allowed.
2. Days 2 to 4: fifteen minutes of timed mental arithmetic twice a day, logging your score and accuracy.
3. Days 5 and 6: probability and expected-value problems with dice, cards and coins, written out and checked.
4. Day 7: sequence and pattern puzzles under a clock.
5. Day 8: a full timed run of every section in one sitting, then rest before the real attempt.

Related guides: what an online assessment is, the HackerRank assessment guide, Optiver coding interview questions.

On the day, and the mistakes to avoid

1. Block the full time the invitation states in one quiet sitting; once started, there may be no reset.
2. Use a laptop with a mouse, and keep the same input device for every game.
3. Keep paper and a pen for working, and put the calculator away if the rules forbid it.
4. Read each test's scoring note: when wrong answers cost points, decide your guessing rule before you start.
5. Close messaging apps and silence notifications; on a test of ten questions a minute, one lost minute is ten questions.
6. Finish every section and wait for the confirmation screen.

Mistakes that cost candidates:

• Practicing arithmetic slowly and accurately but never at test speed.
• Spending a minute on one sequence when the next five are easier.
• Starting the attempt on a work laptop or weak connection when no reset is offered.
• Ignoring the personality questionnaire; trading firms use the profile in later interviews.
• Going silent in later interviews: firms want to hear how you estimate and check, not only the final number.

What happens after the Optiver online assessment

Passing the tests usually leads to a recruiter or HR conversation and technical interviews where mental maths, probability and market questions are asked out loud, then a final round of several interviews, sometimes with a trading simulation. Prepare to explain your reasoning as you calculate, because interviewers listen to the process as well as the answer. For the next stage, see our quant interview prep guide.

Where CoPilot Interview fits

Online assessments are tests you take on your own: outside help is not allowed, and proctoring settings can flag other apps, tab switches or a second voice. Practice beforehand instead. CoPilot Interview is an AI interview assistant; its free AI mock interview prepares you for the interviews that follow the assessment, with questions built from your résumé and the job description and each spoken answer scored out of ten. The free plan gives 15 minutes a day of live help in sessions of up to 15 minutes, with AI mock interviews included. Read the invitation carefully and follow your employer's rules.

Disclosure: CoPilot Interview is our product, so weigh what we say about it accordingly.

Frequently asked questions

What is the Optiver 80 in 8 test?

A mental maths test of 80 multiple-choice arithmetic questions in 8 minutes without a calculator, as prep providers describe it. Wrong and skipped answers are reported to cost a point each.

Can I retake the Optiver assessment?

Not within eight months. Optiver says assessments can be completed only once every eight months and that it cannot offer resets or retakes once an attempt has started.

Do Optiver software engineers take the trading tests?

The trading battery is described for trading and research roles. Optiver describes its software engineering interviews as technical discussions on data structures, algorithms, memory, concurrency and networking, in C++, Java or Python.

What happens after the Optiver tests?

Prep providers describe a phone HR interview, a technical interview and then an interview day; for traders that day includes further interviews and a market-making simulation.

Can I use AI tools during the Optiver online assessment?

No, unless the instructions explicitly allow it. Assessments are meant to be taken on your own, and proctoring settings can flag other apps, tab switches or pasted code. Use AI tools to practice beforehand, and follow your employer's rules.