Prep guide
Optiver's 80 in 8 Practice Test: Mental Math Screening Guide
Eighty short arithmetic problems, eight minutes, no calculator. This page explains what recruiters are measuring and links to QuantKing practice you can run again whenever you want.
Use it alongside other online assessment practice for quant and trading interview prep.
Independent practice guidance. QuantKing is not affiliated with Optiver.
No QuantKing Pro required. Click here to practice.
What is Optiver's 80 in 8?
What is it
Optiver's 80 in 8 is a high tempo mental arithmetic screen used in early trading and quant hiring. You face a large batch of short numeric questions under a strict time cap, with no calculator and no room for wordy reasoning.
The goal is to measure numerical fluency, working memory, and accuracy while the clock is running, not to test formal theorem style work.
How it works
The standard shape is eighty questions in eight minutes: one prompt at a time, type an answer, then move on. Wrong answers usually cost points, skips are neutral, and the overall score is a balance of speed and precision.
Each new practice run shuffles in a fresh mix of items so you are not memorising the same eighty every time.
If you are also preparing for pattern tests, see Optiver NumberLogic or flows with several mini games such as Zap N practice.
How to prepare
Build automaticity on basics: multiplication tables, clean division, percent of a number, fractions to decimals, and tight estimation so you catch typos.
Train in conditions that match the real screen: standing or sitting upright, phone away, full length timed blocks, and short recovery between attempts.