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The Optiver 80 in 8 test: what it is and how to practise

Optiver, a trading firm, starts its hiring for trading roles with an 8-minute numerical test. Candidates call it "80 in 8", for 80 questions in 8 minutes. It is mental arithmetic, so what decides the score is speed and accuracy on school-level sums, and the best preparation is to practise exactly that: sums done in your head, against a clock.

Practise timed arithmetic See the 80-question speed run Practise for this test

What Optiver says, and what candidates report

Length	8 minutes (Optiver)
Content	Basic mathematical calculations, to be done as quickly and as accurately as possible (Optiver)
Calculator	Not allowed at any time (Optiver)
Where it sits	The first step of the application for trading roles (Optiver), followed by other assessments and interviews
Number of questions	Not given in the Optiver pages we found. Candidates and preparation sites commonly report 80, with four answers to choose from
Scoring	Not given in the Optiver pages we found. Candidates report that wrong answers lose marks, and reports differ on how many

Rows marked Optiver come from Optiver's own numerical test site; the rest is candidate reports, not confirmed by Optiver. Optiver itself says there is a lot of information out there about its process and suggests asking its recruiters what is true, so ask them or read the instructions on the day. preplaud gives no pass mark: figures quoted online are candidates' estimates, and Optiver does not publish one.

What the sums look like

Optiver describes basic calculations. The usual shape of trading-firm arithmetic screens is addition, subtraction, multiplication and division with whole numbers, decimals and fractions. The practice here covers that range:

Adding and subtracting three-digit numbers.
Multiplying a two-digit number by one digit, then two by two, then three by two.
Dividing: exact divisions first, then ones with decimals.
Decimals, fractions and percentages.

The mental arithmetic page lists the shortcuts, each with a worked example: split one factor, round and adjust, multiply by 11, and so on.

How to prepare

Learn the shortcuts untimed first, until you reach for them without thinking.
Then add the clock. Timed arithmetic gives each sum a limit, and the level rises as you get them right.
Sit full-length runs. Eight minutes of constant arithmetic is tiring in a way short practice does not show. The 80-question speed run here has a new set of typed questions each time and shows right, wrong and right minus wrong.
Settle your rule for hard sums before the day. If wrong answers cost marks, a stubborn sum is a decision to make quickly. Decide how you will handle it while practising, and check the real rules in the instructions.
Optiver's own advice on its US campus FAQ is that it may help to practise activities that involve quick problem-solving, such as mental maths and strategy games.

Not covered here

Optiver's hiring also includes other online assessments and interviews. preplaud has probability questions and practice versions of reaction, attention and risk games, but it does not copy or claim to match any of Optiver's other assessments.

Start now

Mental arithmetic practice here is free up to level 3, timed or untimed. The full run of 80 typed sums in 8 minutes comes with paid access.

Practise timed arithmetic Shortcuts for fast sums

Sources

Optiver: Numerical Test (8 minutes, basic calculations, no calculators, first step for trading roles)
Optiver: US campus recruiting Q&A (advice on preparing for the online assessment; mental maths "necessary but insufficient")

preplaud is independent. It is not affiliated with or endorsed by Optiver or any other trading firm, and its questions are its own, generated here, not copied from any Optiver test. Optiver's name is used only to describe what the practice is for.