Interview practice
Optiver-style 80-in-8 mental math practice
A global market maker headquartered in Amsterdam, trading options, ETFs and futures on major exchanges.
Candidates widely report an 80-questions-in-8-minutes arithmetic screen early in the process - it is the assessment this format is named after.
What this assessment looks like
A speed-arithmetic screen: on the order of 80 questions in 8 minutes, so roughly six seconds per answer. Addition, subtraction, multiplication, division, fractions, decimals and percentages, often with negative marking - a wrong answer costs more than a skip.
- Two-digit multiplication and division without writing anything down
- Fraction and decimal conversion at a glance
- Percentage moves in both directions (a 20% drop needs +25% to recover)
- Knowing when to skip: negative marking punishes guessing
Train it here
- Arithmetic Drill - 2.5 timed minutes of exactly this question mix, with a ghost of your best past run to race.
- Dino Dash - Endless mental-math runner - one mistake ends the run, and the questions climb through ten difficulty tiers.
- Sequence Sprint - Pattern recognition under the same per-question time pressure.
Also reported at Optiver
Number sequences · Probability & estimation · Market making · Quant developer coding
Outcry is not affiliated with Optiver and has no access to their assessment content. This page describes formats candidates publicly report, and the drills here train the underlying skills - they are not the firm’s questions.