Risk simulator
Position Sizing Game
Test how win rate, payoff ratio, drawdown, and risk per trade interact over a run of trades.
MarketMates experiments
Marble Lab
Small, practical tools for thinking clearly about trading risk, behaviour, and decision quality. No fluff. Minimal goblins.
Why Marble Lab?
We learned a lot about trading by playing the marble game.
The idea was simple: put a bunch of marbles in a hat, each one marked with an R-multiple — -1R, +0.5R, +2R, and the odd unpleasant one you’d rather not pull twice before lunch.
Then you draw them one at a time.
You can’t control the next marble. That’s the point. But you can control how much you risk, how you size your trades, and whether your system can survive a rough sequence of pulls.
That little exercise teaches a lesson most traders need to feel, not just read: trading is not about predicting every single outcome. It’s about understanding the mix in the hat, managing risk, and staying in the game long enough for your edge to show up.
Marble Lab is built in that spirit — simple tools to help you see risk, reward, drawdown, and decision quality more clearly before the market starts throwing marbles at your head.
Objective calculator
Position Sizing Calculator
Estimate 1R, expected return, expectancy, and Monte Carlo drawdown from your trading objectives.
Growth modeller
Compounding Returns Calculator
Model smooth growth, variable monthly returns, percentile outcomes, and drawdown estimates over time.
Drawdown lesson
Drawdown Recovery Calculator
See the return required to recover from a drawdown, with simple bars, a curve, and a quick reference graphic.
Expectancy tool
Edge Simulator
Explore win rate, payoff, R-multiples, expectancy, and simulated equity paths.
Scale-in maths
ATR Scale-In R Multiple Calculator
Compare stop distance, scale-in spacing, and ATR move size to see gross scaling impact in R multiples.
Statement analyst
R-Multiple Analyst
Upload an MT5 XLSX statement and review closed trades using a fixed dollar value for 1R.