💀 Survival math

Risk of Ruin

The probability your account hits zero given your win rate, R:R, and risk-per-trade. Pros target under 1%. Negative-edge strategies make ruin certain — no risk size will save you.

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Pro target
< 1%
Danger zone
10%+
No edge
100% certain
Calculation
live

Probability of busting the account

Risk of Ruin
Edge per Trade
Bankroll Units
The math. With positive expected value (win rate × R:R > 1 − win rate), smaller risk-per-trade dramatically lowers your ruin probability. With negative expected value, ruin is certain regardless of how small you risk per trade — the math just gives you more time before the account goes to zero. Use this to validate that your edge is real before scaling, and to size risk such that ruin is statistically negligible.