Risk Management

Position Size Calculator: The Secret to Survival

By Rahul Kumar | Last Updated: December 2025

Trading Position Size

The number one reason traders blow up their accounts is not "bad strategy" but incorrect position sizing. If you buy too many shares, a single small drop in the market can wipe out 10% or 20% of your capital.

Position Sizing answers the most critical question in trading: "How many shares should I buy so that even if my Stop Loss hits, I only lose a small amount (like 1%) of my portfolio?"

1. Gambler vs Trader: A Scenario

Let's compare two traders who both have ₹1,00,000 capital and take a trade with a ₹10 Stop Loss.

Feature Trader A (Gambler) Trader B (Professional)
Strategy Buys Random Quantity (e.g., 2000 shares) Calculates Risk First (e.g., 100 shares)
If Stop Loss Hits Loss: ₹20,000 (20% of Capital!) 😱 Loss: ₹1,000 (Only 1% of Capital) ✅
Result Panic & Emotional Trading Calm & Ready for Next Trade

Trader A is destroyed after 5 bad trades. Trader B can survive 100 bad trades in a row!

2. The Golden 1% Rule

Professional traders never risk more than 1% or 2% of their total trading capital on a single trade.

The Rule

"I will position my trade size such that if my Stop Loss is hit, I do not lose more than 1% of my total account balance."

3. The Mathematical Formula

How do we calculate the exact quantity to achieve this safety? The math is simple but powerful.

Step 1: Calculate Risk Amount
Total Risk = Total Capital × Risk % (e.g., ₹1 Lakh × 1% = ₹1,000)
Step 2: Calculate Risk Per Share
Risk Per Share = Entry Price - Stop Loss Price
Step 3: Calculate Quantity
Quantity = Total Risk / Risk Per Share

4. How to use our Position Size Calculator?

In a live market, you cannot sit with a pen and paper. Use our tool for instant results:

  1. Account Capital: Enter your total trading balance (e.g., ₹5,00,000).
  2. Risk Percentage: How much are you willing to lose? (Recommended: 1% or 2%).
  3. Entry Price: At what price are you buying?
  4. Stop Loss Price: Where will you exit if wrong?

The tool will instantly tell you:

  • Exact Quantity to buy.
  • Total Capital Required for the trade.
  • Max Loss Amount (It will match your 1% limit).

Protect Your Capital First

Don't guess your quantity. Calculate it.

Calculate Position Size