PRACTICE GUIDE FLOW TRADERS
Flow Traders Market Making Practice Test
Flow Traders does not publish the shape of its market making screen, and candidates describe it as 6 to 20 questions in 10 to 30 minutes, roughly one to three minutes per question, answered by typing the number, with no calculator.
Those are ranges across firms running this format rather than Flow Traders's own figures, so treat them as the shape to train against and check the instruction screen on the day for the marking rule.
Outcry is not affiliated with Flow Traders and has no access to their assessment content. This guide describes an assessment format that candidates report publicly; the questions here are generated by Outcry and are not Flow Traders’s own.
What it screens
A liquidity provider specialising in ETFs, with offices in Amsterdam, New York, Cluj, Hong Kong and Singapore.
- ✓Setting a bid-ask spread that reflects your uncertainty
- ✓Updating quotes after a fill (adverse selection - the person who traded knows something)
- ✓Inventory management: skewing quotes to flatten a position
- ✓Hedging exposure instead of letting it build
Where it sits at Flow Traders
A liquidity provider specialising in ETFs, with offices in Amsterdam, New York, Cluj, Hong Kong and Singapore. What that means for the screen is that the questions tend to be drawn from the work rather than from a textbook, so the format below is the shape to train against rather than a syllabus.
Candidates also report 3 other screens at Flow Traders, covered separately on this site. Where a firm runs several, they usually sit in one round rather than spread across the process, so the pacing of the whole set matters more than any single section.
The format
Flow Traders does not publish this screen's shape, and it varies between firms, so these are the ranges candidates report rather than exact figures.
| Questions | 6 to 20 |
|---|---|
| Time | 10 to 30 minutes |
| Per question | one to three minutes |
| Negative marking | No |
| Answer style | Typed price, spread or size |
| Where it sits | Later round, often live with a trader |
What it tests, with a worked example
Every example below is generated by Outcry, drawn from the same question generators the timed drills run. None of them is Flow Traders’s.
Pricing under partial information
Half the board is hidden, and the quote has to price what you cannot see.
Example
HOW IT SCORES One of the 13 rows is drawn at random as the winning row. Every row is equally likely. A letter scores its own row number minus the winning row number, and a wager pays that score in dollars per unit. ROW LEFT RIGHT --------------------- 1 Q I 2 V F 3 S H 4 K L 5 T M 6 U X 7 ? ? 8 ? ? 9 ? ? 10 ? ? 11 R E 12 B D 13 Y Z Rows 7 to 10 are face down. Between them they hold A, C, G, J, N, O, P, W, but not in any stated order.
A wager on G plus N pays both scores added together. What is one unit worth, in dollars?
Answer 3
Each is equally likely across rows 7 to 10, averaging 8.5, so each leg is worth 1.5. Two legs give 3. Knowing they cannot share a cell does not change either average.
Adverse selection
Whoever trades with you may know something. Size and spread are the defence.
Example
HOW IT SCORES One of the 13 rows is drawn at random as the winning row. Every row is equally likely. A letter scores its own row number minus the winning row number, and a wager pays that score in dollars per unit. ROW LEFT RIGHT --------------------- 1 X L 2 P B 3 G C 4 F Q 5 M T 6 N E 7 I J 8 Z W 9 R U 10 Y K 11 S A 12 V D 13 O H
A counterparty has already seen the winning row. You have not. They offer to sell you one unit of U at 1, and they make that offer only when selling is good for them. What is the expected profit in dollars if you buy?
Answer -3
Unconditionally U is worth 2, so 1 looks like 1 of edge. But they only offer when the score is below 1, which is 5 of the 13 rows: scores 0, -1, -2, -3, -4, averaging -2. The trade you actually get is worth -2 - 1 = -3. The offer itself is the information.
Option mechanics
Payoffs, parity and moneyness, at the speed a trading floor asks them.
Example
The stock is $50 and moves in two steps of 12 months each. Every step it multiplies by 1.15 or by 0.85. The rate is 2%. What is the $53 call worth today?
Answer 4.06
Per step, q = (e^(rT) - d)/(u - d) = 56.73%. The three terminal nodes are $66.12, $48.87 and $36.13, paying $13.12, $0.00 and $0.00. Weighted by q^2, 2q(1-q) and (1-q)^2 that is $4.22 at expiry, discounted over two steps: $4.22 / 1.0408 = $4.06. The middle node needs the factor of 2 - there are two paths through it.
The Greeks
Delta, gamma, vega and theta as directions rather than formulas.
Example
You are long 50 of the 3 month at the money calls. The stock sits still all week. What is theta doing to you?
- Theta is negative - the position bleeds value as the days pass.
- Theta is zero while the stock does not move.
- Theta only bites in the final week.
- Theta is positive - time is on the side of a long option.
Answer Theta is negative - the position bleeds value as the days pass.
A long option is long time value, and time value only goes one way. With the stock still, nothing is earned back - gamma pays only when the stock actually moves, and it has not. Theta is negative for every long option, call or put, and it runs every calendar day including the weekend, not just the last week.
Sizing the trade
How much to do at your own price, which is a different question from what the price is.
Example
HOW IT SCORES One of the 13 rows is drawn at random as the winning row. Every row is equally likely. A letter scores its own row number minus the winning row number, and a wager pays that score in dollars per unit. ROW LEFT RIGHT --------------------- 1 G A 2 V O 3 E R 4 I Q 5 K L 6 Y X 7 N S 8 H W 9 T U 10 Z B 11 M P 12 J D 13 F C
You cannot lose more than $60 on this position under any outcome. What is the largest whole number of units of A you can hold?
Answer 5
The worst case is row 13 winning, which costs 12 a unit. 60 ÷ 12 = 5, so 5 units. Sizing on the worst case is a different number from sizing on the average.
Talking while you think
These rounds are scored on the reasoning you say out loud, not only the number you land on.
What a good score looks like
There is no score to report on most of these. Market-making rounds are judged on the reasoning you narrate as much as the number you land on, which is why candidates describe them as the hardest round to prepare for and the easiest to improve at.
How to train for it
- 01Get fast on fair value first. You cannot quote around a number you are still computing.
- 02Play a round where you get filled and have to re-quote. The update is what the round is actually testing.
- 03Separate the two questions every time: what is it worth, and how much will I do. Answering them together is what produces an indefensible quote.
TRAIN IT HERE
The drills that match each section
Market Maker
Quote spreads, take fills, and manage inventory against informed flow.
Poker Market Making
Make a market on the sum of card ranks and requote as each card is revealed.
Basket Arbitrage
Spot mispricings between a basket and its components before they close.
Delta Defender
Keep a book hedged as the underlying moves - free to play.
SIT THE FULL BATTERY
All the sections back to back on one clock, marked the way the real screen marks them, with a by-skill breakdown at the end. Included with any pass.
Also reported at Flow Traders
Common questions
- Is the Flow Traders market making test multiple choice?
- Reported as typed price, spread or size. Formats move, so treat this as the shape rather than a guarantee.
- How long is the Flow Traders market making test?
- Candidates report 6 to 20 questions in 10 to 30 minutes, roughly one to three minutes per question.
- Is there negative marking on the Flow Traders market making test?
- No. A wrong answer costs nothing beyond the mark you would have earned, so leaving an item blank is never better than guessing at it.
- How do I practise for it free?
- Every drill linked on this page is free to play, with no account, inside a daily run cap. Questions are generated fresh each run, so there is nothing to memorise between attempts.
Hiring now: current Flow Traders quant openings, refreshed daily.