Stop Loss Calculator: Points and Percentage

This stop loss calculator converts an entry price and stop price into a price distance, percentage distance and planned rupee loss. Stop Loss % expresses the distance as a percentage of entry price. Account risk also depends on your quantity and capital. Enter total units in Quantity/Lots: the current implementation uses that number directly, even for derivatives. Lot Size (for F&O) determines the separate Risk Per Lot output. The result assumes an exit at your entered stop and excludes charges; it cannot guarantee your actual loss.

The stop-loss percentage formula

Stop Loss Points = the absolute difference between Entry Price and Stop Loss Price. Stop Loss % = Stop Loss Points ÷ Entry Price × 100. The absolute difference means the form shows a positive distance whether the stop is above or below entry.

For a long position, where you bought first, a protective stop normally belongs below entry. For a short position, where you sold first, it normally belongs above entry. This form has no direction selector, so a positive result does not confirm that you placed the stop on the appropriate side.

Total Risk Amount = Stop Loss Points × total units entered in Quantity/Lots. Risk Per Lot = Stop Loss Points × Lot Size (for F&O). The lot size is not multiplied into the quantity field’s total when that quantity has been entered.

This distinction is essential for derivatives. Convert the number of lots into the actual contract units before completing Quantity/Lots. For cash shares, enter the share count and use a lot-size value of 1. A label alone cannot tell the calculator which market or contract you meant.

Four ways to choose the stop level

The calculator accepts a stop price you have already chosen. These are four common ways to choose it. None is proven best, and each has a downside.

A percentage stop at a made-up entry of ₹800 shows how the distance scales: 1% is ₹8, 2% is ₹16 and 3% is ₹24. That is arithmetic, not a suggested percentage. Read how to calculate a stop loss and the ATR calculator to go deeper on the last two methods. Intraday traders also use stops very close to entry, which leaves little room for ordinary price noise, so test any choice on a sample of your own trades.

Check contract quantity before accepting the total

As of 15 October 2026, the NSE market-lot file lists NIFTY at 65 and BANKNIFTY at 30 for its October, November and December 2026 series. Select the quantity for your contract rather than relying on old help text in a tool. Lot sizes can differ by instrument and series.

The visible form accepts Entry Price, Stop Loss Price, Quantity/Lots and Lot Size (for F&O). There is no capital, target, direction, volatility or trailing-distance field. It therefore cannot select an optimal stop, choose a position size from your account balance or calculate a reward-to-risk ratio from your target.

If you begin with a cash risk budget instead of an existing quantity, the risk per trade calculator addresses the budget calculation. Keep its assumptions separate from the amount this page calculates for a position you already specified.

From stop distance to quantity

You can also work in the other direction. Divide the rupee loss you accept by the stop distance per unit, then round down to a quantity you can trade. In the made-up Nifty example the distance is 150 points. With a budget of ₹10,000, the raw quantity is 10,000 ÷ 150 = 66.67 units. Index futures trade in whole lots of 65 units, so the budget fits one lot: planned loss for that lot is 150 × 65 = ₹9,750, which leaves ₹250 unused. A second lot would add another ₹9,750 and break the budget.

For cash shares, the same 66.67 would round down to 66 shares. To do this with a capital figure and a risk percentage, use the risk per trade calculator or the Nifty position size calculator. Then type the final unit count into Quantity/Lots here to see the total.

Worked Nifty example: total units versus lots

Illustrative prices, not a current quote: Entry Price 25,000 and Stop Loss Price 24,850. Assume NIFTY futures contracts from the October 2026 series and a position of 2 lots. With the listed lot size of 65, total quantity is 2 × 65 = 130 units. Enter 130 in Quantity/Lots and 65 in Lot Size (for F&O).

If you instead enter 2 into Quantity/Lots, the current form calculates 150 × 2 = ₹300 as Total Risk Amount. It does not convert those 2 lots into 130 units. That is why the total-unit entry matters even when the separate Risk Per Lot figure looks correct.

For a separate account comparison, suppose the trading capital is an illustrative ₹3,00,000. The planned ₹19,500 price loss is 19,500 ÷ 3,00,000 × 100 = 6.5% of that capital. The tool’s 0.60% Stop Loss % and the hand-calculated 6.5% account risk use different denominators. There is no capital field here to make that comparison automatically.

An index-price stop describes an index-price move. If you are trading an option, the premium may change differently. Do not multiply an index stop distance by an option quantity and call the result the option’s planned loss. Use the entry and exit prices of the actual traded instrument on a consistent scale.

Stock and short-position examples

Made-up cash-share example: enter ₹800 as Entry Price, ₹784 as Stop Loss Price, 25 shares in Quantity/Lots and 1 as Lot Size. Distance is ₹16 per share, Stop Loss % is 16 ÷ 800 × 100 = 2%, and Total Risk Amount is 16 × 25 = ₹400. Risk Per Lot is ₹16 because the entered lot-size multiplier is 1.

For a separate illustrative short position sold at ₹800 with a protective stop at ₹816, the absolute distance is also ₹16. At the same quantity, the displayed percentage and planned price loss are unchanged. The form calculates a distance; it does not check whether shorting or that order type is available for a particular product.

If you only know a desired percentage, a hand calculation can find a candidate price. With an illustrative long entry of ₹800 and a chosen distance of 2%, the price is 800 × (1 − 2 ÷ 100) = ₹784. That is an assumed plan, rather than a stop recommended by this calculator.

Stop loss and target from a risk-reward ratio

This form works out the stop side only. If you also want a target, you can build one from the same distance and a reward-to-risk ratio that you choose. The ratio is a planning number. It does not predict that price will reach the target.

• Long trade: target = entry + ratio × (entry − stop).
• Short trade: target = entry − ratio × (stop − entry).

Using the earlier made-up Nifty prices: entry 25,000, stop 24,850, so the distance is 150 points. With a ratio of 2, the reward distance is 2 × 150 = 300 points and the target is 25,000 + 300 = 25,300. For the made-up short at ₹800 with a stop at ₹816 and a ratio of 1.5, the distance is ₹16, the reward distance is 1.5 × 16 = ₹24 and the target is 800 − 24 = ₹776. A higher ratio puts the target further away, which means price must travel further to reach it. See how to calculate the risk reward ratio for more.

What a trailing stop loss means

A trailing stop changes its trigger as price moves favourably while holding that trigger when price moves against the position. Fidelity’s order explanation describes this mechanism. Actual order availability, trigger basis and monitoring depend on the broker and product.

Illustrative sell-trailing calculation: if the tracked high is ₹520 and your chosen trail is 2%, the reference trigger is 520 × (1 − 2 ÷ 100) = ₹509.60. If that tracked high later reaches ₹540, the reference becomes ₹529.20. Under this assumed trailing rule, a subsequent lower price does not lower the trigger.

Those trailing calculations are educational examples outside this form’s outputs. The calculator has no moving price record and will not update or place a trailing order. To compare chart-based reference levels, see the pivot point calculator; such a reference does not make an exit certain.

A trigger price is different from an execution price

The NSE trading-system explanation describes a stop order as becoming active when its trigger condition is reached. Activation is a separate event from a completed trade. Check the trigger and limit fields in your broker’s order ticket.

NSE’s risk disclosure warns that rapid market movements can make intended loss-limiting orders ineffective and that a limit order may not execute. Actual loss can therefore exceed the price-distance estimate, especially when the available exit price differs from the assumed stop.

The calculator also omits brokerage, taxes and other transaction charges. When reviewing an actual exit, compare the planned stop with the fill price and after-cost result. The risk reward calculator can compare planned distances; your trade record is needed to explain what actually happened.

Stop loss on an option premium versus the underlying

If you buy an option, the stop that matters for your money is the premium, because the loss is the premium fall times the units. Enter the option's own entry premium and stop premium in this form. An index level stop is a different thing. A move in the index changes the premium by an amount that depends on strike, time left and implied volatility (the market's expected size of moves), and that amount changes as price moves.

A made-up premium example: entry ₹100, stop ₹70, 65 units. Distance is ₹30, Stop Loss % is 30 ÷ 100 × 100 = 30%, and Total Risk Amount is 30 × 65 = ₹1,950. A 30% premium stop is a large percentage because premiums move fast. The percentage shown here is a share of premium, not of the index.

SL and SL-M orders, and the risk of a gap

Indian brokers offer two stop order types. An SL order has a trigger price and a limit price. Once triggered it becomes a limit order, so it fills only at the limit or better. An SL-M order becomes a market order when triggered, so it is more likely to fill but at whatever price is available. NSE circular NSE/FAOP/49677 (21 September 2021) said SL-M orders would be discontinued for index and stock option contracts from 27 September 2021, while stop-loss orders with a limit price stay available. We have not rechecked the current rule for every product, so check which order types your broker offers today.

A gap is the reason a stop can fill worse than planned. Using the made-up Nifty position of 130 units with a stop at 24,850, suppose the next trade after a gap down is at 24,700. The loss per unit is 25,000 − 24,700 = 300, not 150, so the loss is 300 × 130 = ₹39,000 instead of ₹19,500. With a plain SL order, the limit may not be reached at all, and the position stays open. Neither order type guarantees an exit at your stop.

Stop loss calculator questions

Sources

• NSE: contract market-lot file, checked 15 October 2026.
• NSE: derivatives trading system and stop activation, checked 15 October 2026.
• NSE: execution-risk disclosure, checked 15 October 2026.
• Fidelity: trailing-stop mechanism, checked 15 October 2026.