Position Size Calculator
The right lot size is the one that makes your worst case survivable. Enter your balance, the percentage you're willing to risk, and your stop distance.
Position size
0.50lots
Amount at risk
100
Rounded down to two decimals — never risk more than you intended. Verify the contract size and pip value for your instrument with your broker; slippage and gaps can exceed your stop. This is a calculator, not financial advice.
How it works
The maths is simple: your risk amount is your balance times your risk percentage. Divide that by your stop distance in pips times the pip value per lot, and you have the position size that loses exactly your intended amount if the stop is hit.
The hard part isn't the arithmetic — it's that the trade where you most want to override the answer is the trade where the answer matters most. A calculator tells you 0.47 lots; it can't stop you typing 2.0 after three losses.
Related reading
Want the number enforced, not just calculated? Risk Marshal caps lot size automatically on your MT5 account — the oversized trade gets resized or blocked at execution.
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