The competitive training platform for quant interviews
Train for quant interviews like a competitive sport.
Timed mental math drills, original probability and brainteaser problems, and a public proof-of-skill profile. Speed, reasoning, and trackable progress — in one place.
Three pillars
01
Mental Math Arena
Five timed drill modes — quick-fire arithmetic, percentages, fractions, expected value, and sequences — scored and rated so you can watch your speed compound.
02
Probability & Brainteasers
An original, quant-interview-style problem bank with server-checked answers, hints, and full editorials that teach the underlying technique — not just the trick.
03
Public Quant Profile
Streaks, ratings, badges, and solve history on a public profile — verifiable proof of skill you can share, not just claims on a resume.
Why QuantOS
Quant prep today is fragmented.
Mental math drills live on one site, probability questions in scattered PDFs and forums, and there is no record of any of it. You grind, but nothing accumulates — no measurable progress, nothing to show for it.
QuantOS makes training compound.
One platform combines speed work, probabilistic reasoning, and trackable progress. Every round and every submission updates your stats, streaks, and training ratings — so preparation behaves like a sport: deliberate, measured, and competitive.
What's in the platform
Timed drills
Five mental math modes with server-generated questions and a hard clock.
Original problem bank
Probability, combinatorics, statistics, and brainteasers — written for QuantOS, verified, and tagged.
Ratings & streaks
Training ratings that move with your performance, plus daily streak tracking.
Editorials
Every problem ships with a hint and a full editorial explaining the reasoning.
Ready to put in the reps?
Sign up, run your first mental math round, and start a streak today.
QuantOS is independent and uses original educational content. It is not affiliated with, endorsed by, or sponsored by any trading firm.