Lot Size Calculator
Calculate the exact position size for any trade across 200+ instruments. Forex, crypto, stocks, indices, commodities — with real-time exchange rates.
Enter entry price and stop loss to calculate
This calculator is provided for informational and educational purposes only. It does not constitute financial advice. Always verify position sizes and risk parameters with your broker before placing any trade.
How to Use the Lot Size Calculator
Position sizing is the single most important risk management skill in trading. A perfect entry with wrong lot size can blow your account. A mediocre entry with correct lot size keeps you in the game.
The Formula
Where Risk Amount = Account Balance × Risk Percentage. If you have a $10,000 account and risk 1%, your risk amount is $100.
Why Truncation, Not Rounding?
This calculator uses truncation (floor) instead of rounding. If the math says 0.837 lots, we output 0.83 — not 0.84. Rounding up would mean risking more than your intended percentage. Professional risk management always errs on the side of caution.
The 1% Rule
Never risk more than 1-2% of your account on a single trade. With 1% risk, you can lose 10 trades in a row and still have 90% of your capital. With 5% risk, 10 losses leaves you with only 60% — a 67% gain needed just to break even.