Optiver runs one of the most speed-driven interview processes in trading. Clearing the early numerical tests is the gate; everything interesting comes after.
The 80-in-8 test
Optiver is best known for its "80 in 8" assessment — widely reported as 80 arithmetic questions in 8 minutes, no calculator, with a penalty for wrong answers. That is roughly six seconds per question. A number-sequence test (spot the rule, give the next term) usually follows.
Watch out. Specific counts and timings are commonly reported rather than officially published, and they shift year to year. Don't over-index on a single figure — index on the skill: fast, accurate arithmetic and pattern recognition under brutal time pressure. The arithmetic is basic (integers, decimals, fractions, percentages); the pace is what eliminates most applicants.
The process
| Stage | Focus |
|---|---|
| Online assessment | "80 in 8" mental math + number sequences |
| Interviews | Probability, expected value, market-making games |
| Final round | Trading judgement and fit with senior traders |
The later rounds cover probability, expected value, and market-making and betting games — quoting a two-sided price, managing risk, and updating on new information. Optiver wants traders who are fast and sound under uncertainty, not merely quick calculators.
How to prepare
Key insight. Win the arithmetic first. Nothing else on your application matters until you clear the speed filter, so that is where early prep should concentrate.
- Arithmetic and sequences. Drill the Mental Math Blitz and Number Box until speed is automatic — see the speed mental-math guide and the sequence-tests guide.
- Then judgement. Work probability and market-making problems, and practise quoting with the Make a Market game.
- Simulate the OA. Run the timed Probability OA — the OA guide explains the penalty-scoring strategy.
When you are ready, work the Optiver question set.