The risk of ruin — sizing for survival
The math that keeps an account alive. Position sizing isn't the boring part — it's the whole game.
- →Risk of ruin rises non-linearly with position size.
- →A fixed-fractional approach protects against tail runs.
- →Survival first — returns compound only if you're still here.
Every trader eventually meets a losing streak. The question is whether your account survives it. Risk of ruin is the probability that a series of losses wipes you out — and it climbs frighteningly fast as size increases.
The non-linear trap
Doubling your risk per trade does not double your risk of ruin — it multiplies it. Small, consistent fractions of capital keep the math on your side through inevitable drawdowns.
Fixed-fractional sizing
Risking a fixed small percentage per trade means your bet shrinks as the account does, slowing the bleed exactly when it matters. It's unglamorous and it works.
Survival is the strategy
Returns only compound if you're still in the game. The position-size calculator isn't an accessory — it's the difference between a career and a story.
For information only — not financial advice. Trading involves risk and may not be suitable for all investors.
Open the desk.
Trade with intention.
Minutes to open. Seconds to fund. Institutional pricing from your first position.
Trading foreign exchange and CFDs carries a high level of risk and may not be suitable for all investors. You could lose more than your initial deposit.