BEST QUANT INTERVIEW PREP TOOLS IN 2026

Nobody gets an offer because of the tool they chose. But picking the wrong one for the stage you are at wastes the two weeks you had, so it is worth ten minutes to get right.

Prices and features below were checked on the providers' own sites on 17 September 2026. They change often, so confirm before you pay. We make one of the tools listed here (Variance), and we say so where it comes up.

There is no single best quant interview prep tool, because a quant process is not one exam. A market-maker screen can open with 80 arithmetic questions in 8 minutes and end with a market-making conversation. A research process can skip the speed test and spend an hour on probability. The tool that fits one stage is usually wrong for the next.

First work out which stage you are training

Most processes are some combination of five filters:

1. Arithmetic speed. Timed mental math, no calculator.
2. Probability and statistics. Expected value, conditional probability, counting.
3. Brainteasers and logic. Puzzles that check how you start, not what you memorised.
4. Market making and trading judgement. Quoting a price and defending it.
5. Behavioural. Why trading, why this firm, what you do when you are wrong.

Buy or download nothing until you know which of these is closest. If your assessment is in four days and it is arithmetic-heavy, a 1,000-question probability bank is the wrong purchase.

The tools, side by side

Arithmetic speed

Zetamac is free, has no account, and is where almost everyone starts. The default is a two-minute game across all four operations. It is a good measure of one thing: how fast you can do simple arithmetic when nothing is at stake.

Its weakness is the scoring. Zetamac has no penalty for a wrong answer and no fixed question count, so it never teaches you to decide whether an answer is worth submitting. Several real assessments subtract a point for a wrong one. Train that separately. Our guide to Zetamac scores covers what a score actually means in seconds per question.

The Wall Street Quants publishes a free mental math test built around the 80-questions-in-8-minutes format, including fractions and decimals, and it scores +1 for a correct answer and −1 for a wrong one. That penalty is the part Zetamac is missing.

TraderMath is paid and covers more ground: arithmetic and sequence drills, market making games, coding problems, and assessment-style tests. It is worth considering if you want several stages in one subscription, though a two-week window at $29.95 is roughly a third of the cost of a book you keep.

Ours: Variance is an iOS app with timed test modes that follow the formats above, including a mode with typed answers and a point off for a wrong one. Every other tool on this page is a website, so Variance is the one that works on the train, in a queue, or anywhere with no signal. All 13 games are free to play. It is not a substitute for working problems with a pen.

Probability, statistics, and question volume

QuantGuide is the closest thing to LeetCode for quant. There is a free tier with non-premium questions, analytics, and a mental math game. Premium runs $20 a month billed annually or $35 monthly, and adds step-by-step solutions across the full bank and filtering by company. If you are early and need volume with explanations, this is the usual pick.

The two standard books still do something no subscription does. A Practical Guide to Quantitative Finance Interviews by Xinfeng Zhou (the "Green Book") is the better one for method, and it goes deeper than most screens require. Heard on the Street by Timothy Falcon Crack sits at a steadier mid-level and is heavier on brainteasers. Fifty Challenging Problems in Probability by Frederick Mosteller is cheap, short, and better than its age suggests.

Our own free sets cover the same ground if you want to try before paying: probability questions, expected value, and combinatorics.

Brainteasers

Brainstellar is free and has around 130 puzzles sorted by difficulty and type, each with the steps written out. For most candidates that is enough. Add Heard on the Street if you want more, and our brainteaser set if you want ten grouped by the habit each one tests.

A warning about puzzle grinding: past a point it stops helping. Interviewers are watching your first move. Once you reliably try a small case, work backwards, or count the information available, another fifty puzzles adds little.

Market making and behavioral questions

This is the stage with the fewest good tools, because it needs another person. TraderMath includes market-making games, and QuantGuide has a community, but the highest-value practice is still quoting prices out loud to a friend who is allowed to hit your bid and ask you why.

Our market making guide and trader interview guide cover the structure: quote a spread, adjust when someone trades with you, and say what would change your mind.

Firm-specific information

Read the firm's own careers page first, then treat everything else as a candidate report with a date on it. Formats change between cycles and roles, and forum threads rarely say which role they came from. Our firm guides keep those two categories separate on purpose, for Optiver, IMC, SIG, Five Rings, Jane Street, and Citadel Securities.

One more thing worth knowing: a lot of the "best prep platform" comparisons you will find are published by the platforms being ranked, including this one. Check who owns the site before you trust the ordering.

A stack that costs nothing

If you have three weeks and no budget, this covers four of the five filters:

1. Daily, 15 minutes. Zetamac on default settings, then one 80-in-8 test with the penalty scoring once a week.
2. Three times a week, 45 minutes. Probability and counting problems with a pen. QuantGuide's free tier or the free sets linked above.
3. Twice a week, 30 minutes. Brainstellar puzzles, timed, writing down your first move before you solve.
4. Once a week. Quote markets with a friend for 20 minutes, then write your answers to "why trading" and one time you were wrong.

That plan beats most paid programs, not because the paid ones are bad but because the limiting factor is usually consistency.

When paying is worth it

Paying tends to help in three situations:

• You need worked solutions because you keep getting answers without understanding the method.
• You have an assessment in under two weeks and want the format practice without assembling it yourself.
• You will not practice unless something tracks it for you.

It rarely helps if you have not finished the free material you already have. A subscription you renew for four months usually costs more than both standard books.

FAQ

What is the best free quant interview prep?

Zetamac for arithmetic speed, Brainstellar for puzzles, QuantGuide's free tier for question volume, and a library copy of the Green Book. Add a weekly 80-in-8 test with penalty scoring so speed practice matches assessment conditions. Our own free tier covers the timed side away from a laptop, and the guides on this site are free to read.

Is QuantGuide or TraderMath better?

They solve different problems. QuantGuide is a question bank with solutions and company filters, and has a usable free tier. TraderMath bundles drills, market-making games, and coding practice behind a subscription. If your weak point is probability, QuantGuide. If it is the trading side, TraderMath. If the problem is that you never sit down at a laptop to practice, neither will help, and that is the gap Variance was built for.

Where does Variance fit?

We built it, so weigh this accordingly. Four things make it different from everything else on this page:

• It is a phone app, not a website. Every other tool here runs in a browser. Practice happens in the ten-minute gaps in your day, and those gaps happen away from a desk.
• It works offline. Every game runs with no connection, so a commute or a flight is usable practice time. Results sync when you are back online.
• The free tier is generous. All 13 games, the daily brief, leaderboards, and every guide on this site, with no payment and no sign-up for the guides.
• It is already in use. Students in more than 40 countries and at 80+ universities train with it.

What it is not: a replacement for the books, or for writing out a probability problem by hand. Use it for the timed, repetitive part.

Do I still need the books?

For research and quant developer roles, yes. The Green Book covers depth that screens rarely reach but interviewers do. For a speed-focused trading screen, drills matter more than the books.

How long should preparation take?

Four to six weeks of consistent daily work is enough for most first screens if the maths is already familiar. See how to prepare for quant online assessments for a schedule.