What is Marble Lab?
Marble Lab is a collection of MarketMates educational trading-risk tools. Use it to explore how position sizing, trading outcomes and costs interact before applying your own trading plan. It models scenarios; it does not place trades.
What does R mean?
1R is the amount you plan to risk on a trade. If your planned risk is $100, a $200 profit is +2R and a $100 loss is -1R. Keeping results in R helps you compare trades with different dollar sizes.
Choose the question you want to answer
Use the Position Sizing Game to experience sequences of wins and losses, the Position Sizing Calculator to estimate dollar risk, or the Edge Simulator to explore expectancy.
Select a growth or risk tool
Use Compounding Returns to compare growth paths, Drawdown Recovery to see the gain needed after a loss, or ATR Scale-In to compare the combined exposure of multiple entries.
Review actual trades or trading costs
Use R-Multiple Analyst with an MT5 XLSX statement to review closed trades. Use Cost of Fees to compare projected growth before and after trading costs.
Compare more than one scenario
Start with realistic assumptions and change one input at a time. Compare drawdown and downside outcomes as well as headline returns; repeat random simulations to see how the sequence can vary.