🎯 What is Lot Size in Options? (Simple Definition)
Lot size is the number of shares or index units in one options contract. You cannot buy fractional lots - you must buy complete lots.
Think of lot size like buying eggs in dozens. You can't buy 5 eggs - you buy 1 dozen (12 eggs). Similarly, you can't buy 25 units of Nifty - you buy 1 lot (50 units).
Example: Nifty lot size is 50. If premium is ₹150 per lot, your total cost = ₹150 × 50 = ₹7,500. You're buying rights to 50 units of Nifty.
💰 Why Lot Size Matters for Your Profit/Loss
Example: Nifty 22,000 Call
If Nifty rises to ₹22,500:
Profit per unit = ₹22,500 - ₹22,000 = ₹500
Total profit = ₹500 × 50 (lot size) = ₹25,000
Net profit = ₹25,000 - ₹7,500 = ₹17,500
📊 Common Lot Sizes in Indian Markets
Nifty 50
Most popular index for options
Bank Nifty
Banking sector index
Sensex
BSE Sensex index
❓ Frequently Asked Questions
What is Nifty lot size?
Nifty 50 lot size is 50 units. This means one Nifty option contract gives you rights to 50 units of Nifty index.
What is Bank Nifty lot size?
Bank Nifty lot size is 15 units. One Bank Nifty option contract = 15 units of Bank Nifty index.
Can I buy half lot or fractional lot?
No, you cannot buy fractional lots. You must buy complete lots. Minimum is 1 lot. If you want less exposure, choose a different instrument or wait for better entry.
How does lot size affect my profit?
Lot size multiplies your profit/loss. If profit per unit is ₹100 and lot size is 50, total profit = ₹100 × 50 = ₹5,000. Always multiply by lot size when calculating total P&L.
Why is lot size different for different instruments?
Lot sizes are set by exchanges to ensure reasonable contract values. Nifty is larger (50), Bank Nifty is smaller (15) because Bank Nifty prices are higher. This keeps contract values similar.
Practice Options Trading with Correct Lot Sizes
Learn lot sizes and profit calculations on Zerroday. Practice with real Nifty & Bank Nifty data and understand how lot size affects your trades.
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