Founder, Underpitch · Source review includes AMFI, SEBI, NSE, RBI, IRDAI, exchange, company or insurer documents where relevant.
2 July 2026
Position sizing decides how many shares or contracts to trade so that a failed trade does not damage the account excessively. First set the maximum rupee loss you can accept, then divide it by the planned loss per share, including likely slippage and charges. The percentage used must reflect your strategy, drawdown tolerance and experience.
Key points
- Choose risk before quantity, not after entering the trade.
- A tight stop can increase quantity and create slippage risk.
- Correlated trades can create one large hidden position.
- Derivative leverage makes contract-level loss much larger than premium or margin shown.
Basic calculation
If account capital is ₹5 lakh and the chosen maximum risk is ₹2,500, a trade with a ₹10 planned loss per share allows roughly 250 shares before charges and slippage. This is arithmetic, not a recommended risk percentage.
Portfolio heat and correlation
Five trades each risking 1% can behave like one 5% risk if all are similar banking or high-beta positions. Total open risk and sector correlation matter as much as risk per trade.
Why position sizing cannot rescue a weak system
Small sizing limits damage, but a strategy with negative expectancy, uncontrolled costs or frequent gap risk will still lose money over time. Review win rate, average gain, average loss and worst drawdown.
Worked Indian example
A trader buys at ₹420 with a planned exit at ₹408, so the chart-based loss is ₹12 per share. The maximum rupee risk is ₹3,000. The theoretical size is 250 shares, but the trader reduces it to allow for slippage and brokerage. If the stock is illiquid, even that quantity may be too large.
Comparison table
| Input | Illustrative value | Meaning |
|---|---|---|
| Trading capital | ₹5,00,000 | Capital used for risk calculation |
| Maximum trade loss | ₹2,500 | Chosen account-level risk budget |
| Entry price | ₹420 | Planned purchase price |
| Stop reference | ₹408 | Invalidation point, not guaranteed fill |
| Loss per share | ₹12 | Before slippage and charges |
| Theoretical size | 208 shares | ₹2,500 ÷ ₹12, rounded down |
Example only. Actual loss can exceed the planned amount.
Risks and limitations
- Gap-down openings can bypass a stop level.
- Leverage can create obligations beyond the expected move.
- Repeated small losses can accumulate into a large drawdown.
- Using total savings rather than dedicated risk capital can threaten essential goals.
Frequently asked questions
Is risking 1% per trade always safe?
No. It is a commonly discussed rule, not a guarantee. Strategy, correlation, gap risk and personal finances matter.
Should the stop be based only on money?
The stop should reflect where the trade idea is invalid, while position size adjusts to the acceptable rupee loss.
Can I increase size after losses to recover faster?
That increases drawdown risk and can lead to ruin. Position rules should be set before emotional pressure.
Does option premium equal maximum loss?
Only for certain long-option positions. Short options and multi-leg strategies can create larger or complex exposure.
Sources and methodology
Rules, thresholds and product terms can change. Verify the latest official material and product documents before relying on a figure.
This page is for education and product understanding. It is not a personalised investment, legal, tax, trading or buy/sell recommendation. Stocks, derivatives, PMS and AIFs can result in partial or total capital loss.