📦 Lot Size Calculator

Lot Size Calculator — Futures & Forex Position Sizing Guide

Calculating the correct lot size is the foundation of risk management in futures and forex trading. Trading too large means a single bad trade can wipe out weeks of gains. Too small, and you leave money on the table. The right lot size is derived mathematically from your account size and risk tolerance.

Lot size formula

Lots = Risk Amount ÷ (Stop Loss × Pip/Point Value per Lot)

Where: Risk Amount = Account Size × Risk %

Always round down to the nearest whole lot — never up — to stay within your risk limit.

Example: Nifty 50 futures lot size calculation

Account: ₹5,00,000 · Risk per trade: 1% = ₹5,000 · Stop loss: 40 points · Nifty lot size: 75

Lots = ₹5,000 ÷ (40 × 75) = 5,000 ÷ 3,000 = 1.67 → round down to 1 lot

With 1 lot, a 40-point adverse move costs 40 × 75 = ₹3,000 — exactly 0.6% of account, within our 1% limit.

Indian futures lot sizes (2024–25)

• Nifty 50: 75 units per lot
• Bank Nifty: 30 units per lot
• Fin Nifty: 125 units per lot
• Sensex: 20 units per lot (BSE)

Lot sizes change periodically — verify on NSE/BSE before trading.

Risk per trade — the 1% rule

• Risk 1%: 10 consecutive losses still leaves 90% capital intact
• Risk 2%: common for experienced traders with proven systems
• Risk 5%+: extremely aggressive — 14 consecutive losses = 50% drawdown
• Beginners: start at 0.5% until your system is profitable on paper first