Risk Per Trade
Definition
Risk per trade is the maximum dollar amount you're willing to lose on a single position if your stop is hit — typically expressed as a percentage of your total account equity (commonly 0.5%–2% per trade) and used as the foundation for calculating proper position size.
Example
“Account equity: $50,000. Risk per trade: 1%. That's $500 maximum loss per trade. If my stop is $1.00 from my entry, I can trade 500 shares. If my stop is $0.25 away, I can trade 2,000 shares. The math tells me the size, not my gut.”
Detailed Explanation
Risk per trade is the single most important input in the trading equation because it directly determines how long you can stay in the game. If you risk 10% per trade and have three consecutive losing trades — which is absolutely normal variance in any trading strategy — you've lost 30% of your account. Recovering from a 30% loss requires a 43% gain just to get back to even. By contrast, if you risk 1% per trade and have three consecutive losers, you're down 3% and need a 3.1% gain to recover. The math of compounding losses is brutal, and the percentage you risk per trade is the primary lever controlling that math.
The 1-2% rule is widely cited not because it's sacred but because it's mathematically sound for most trading systems. At 1% risk per trade with a 40% win rate (below average for many strategies), you'd need approximately 55 consecutive losses to lose half your account — a virtually impossible streak if you're trading with any edge at all. This means consistent 1% risk essentially eliminates ruin risk from bad luck alone. The risk of ruin — the mathematical probability of losing your entire account — drops toward zero as risk per trade decreases, making this single variable the most impactful adjustment any overleveraged trader can make immediately.
Different market conditions and setup qualities can (within reason) justify varying your risk. Some traders use 0.5R on "B-grade" setups and full 1R only on A-grade setups, effectively building selectivity into their position sizing. What you want to avoid is dynamic sizing based on emotional state — sizing up after a loss to recover, or sizing up because you "really believe" in a trade. Those decisions lead directly to variance that blows accounts. The discipline is treating the risk limit as a hard cap, not a guideline, and letting position size float mechanically based on the distance to your stop rather than on how good you feel about the trade.