Free tool
The 80-in-8 mental-math test
The arithmetic screen that filters candidates at Optiver, IMC and other market makers — in the same format, scored the same way, free and without signing up.
The real format · no sign-up
80 questions. 8 minutes. No calculator.
- +1 per correct answer
- −2 per wrong answer
- 0 for a skip
Type the answer and press Enter. Press S (or tap Skip) when the path isn't visible in about two seconds. You get a full breakdown at the end, even if you stop early.
What the test covers
Questions are deliberately unremarkable — the difficulty is the six-second budget per question and the penalty for being wrong:
- Addition and subtraction, often with one decimal place
- Two-digit by one-digit and two-digit by two-digit multiplication
- Division that resolves to a clean answer, e.g.
144 ÷ 0.6 - Percentages of round numbers, e.g.
15% of 240 - Common fractions as decimals, e.g.
3/8
What score do you need?
Firms don't publish cutoffs. Candidate reports put the bar around a net score of 50: attempt 60 or more with very high accuracy. That makes accuracy the first thing to train — a candidate who answers 55 with no mistakes passes, while one who answers 75 at 85% accuracy fails on penalties.
How to get faster
- Train timed from day one. Untimed accuracy is a different skill.
- Fix your weakest operation first. Your results above rank operations by accuracy and speed — drill the top one.
- Adopt the skip rule.If the path to the answer isn't visible in about two seconds, skip. Under −2 a coin-flip guess has negative expected value.
The full format, cutoffs and a week-by-week plan are in the Optiver mental-math round guide.
Questions about the test
- Is this the actual Optiver test?
- No. It's a practice test in the same format candidates describe for the Optiver arithmetic screen and similar market-maker screens: 80 questions, 8 minutes, no calculator, wrong answers penalized. Quant Ladder isn't affiliated with any trading firm.
- How is the test scored?
- +1 for each correct answer, −2 for each wrong answer, 0 for a skip. Because a wrong answer costs twice what a right one earns, skipping a question you can't see the path to is usually the better move.
- What score do I need to pass?
- Firms don't publish cutoffs, and they vary by office and season. Candidate reports cluster around a net score of about 50; candidates who pass comfortably tend to finish 65–75 questions at 95%+ accuracy.
- Do I need an account?
- No. The test runs entirely in your browser with no sign-up. A free account is only needed if you want your runs saved and your per-operation speed and accuracy tracked over time.
- Does it work on a phone?
- Yes — the answer box opens the numeric keypad. Practice on the same kind of device and input method you'll use on test day; input speed is worth several questions.