Position size calculator for Indian stocks
Position size is how many shares to buy so that, if your stop-loss is hit, you lose only the amount you planned. The formula: shares = (capital × risk %) ÷ (entry − stop-loss). With ₹2,00,000, 1% risk, entry ₹500 and stop ₹480, you'd buy 100 shares.
Shares = (₹2,00,000 × 1.00%) ÷ (₹500.00 − ₹480.00) = 100.0 → 100
Brokerage, taxes and slippage are not included. Gaps can make a loss bigger than planned.
- 1Halve the distance to your stop. The shares double — the rupee risk doesn't change.
- 2Set risk to 0.5% and see how small a loss can be kept.
- 3Move the stop above the entry to see why a buy needs its stop below.
How to use the calculator
- 1Enter your trading capital — the money set aside for trading, not your savings.
- 2Choose your risk per trade. Many traders use 1% or less.
- 3Enter your entry price and your stop-loss, taken from the chart — not from what you can afford to lose.
- 4Add a target if you have one, to see the reward and the risk-reward ratio.
- 5Read the number of shares, what they cost, and what you lose if the stop is hit.
The formula, step by step
Shares = (capital × risk %) ÷ (entry − stop-loss). The first part is the rupees you're willing to lose. The second is what you lose on each share. Divide one by the other and round down.
- Capital
- ₹5,00,000
- Risk per trade (1%)
- ₹5,000
- Entry
- ₹1,250
- Stop-loss
- ₹1,200 (₹50 a share)
- Shares
- ₹5,000 ÷ ₹50 = 100 shares
- Position value
- 100 × ₹1,250 = ₹1,25,000
If the stop is hit, you lose about ₹5,000 — 1% of your capital — plus charges, even though you bought ₹1,25,000 worth of shares.
Notice what the formula does not ask: how good the setup looks, how sure you feel, or how much you want to make. It only asks how much you can lose and where the trade is wrong. That's what keeps sizing calm on a busy day.
Always round down. If the maths says 133.3 shares, buy 133. Rounding up adds risk you didn't plan for, and the extra share is the one that turns 1% into a bit more.
Three worked examples
The same rule gives very different share counts, because the stop distance changes from chart to chart. Here are three practice trades on made-up stocks.
- Capital
- ₹50,000
- Risk per trade (1%)
- ₹500
- Entry / stop-loss
- ₹120 / ₹116 (₹4 a share)
- Shares
- ₹500 ÷ ₹4 = 125 shares
- Position value
- 125 × ₹120 = ₹15,000
A tight, chart-based stop lets a small account hold a sensible position while still risking only ₹500.
- Capital
- ₹50,000
- Risk per trade (1%)
- ₹500
- Entry / stop-loss
- ₹640 / ₹600 (₹40 a share)
- Shares
- ₹500 ÷ ₹40 = 12.5, so 12 shares
- Position value
- 12 × ₹640 = ₹7,680
The stop is ten times wider, so the position is much smaller. The rupees at risk stay about the same.
- Capital
- ₹1,00,000
- Risk per trade (1%)
- ₹1,000
- Entry / stop-loss
- ₹250 / ₹248 (₹2 a share)
- Shares by the formula
- ₹1,000 ÷ ₹2 = 500 shares
- Position value
- 500 × ₹250 = ₹1,25,000 — more than your capital
Cap the position at what you can pay for in cash, or at your own limit per stock. Here, 200 shares (₹50,000) risks only ₹400, which is fine — risking less is always allowed.
Set a cap per stock as well
The risk rule protects you from a normal stop-loss. A cap per stock protects you from the rare day a stock gaps far below your stop — on results, news or a market-wide fall. Many traders keep any single stock to a set share of capital, such as 20–25%, whatever the formula says.
With both rules in place, you take the smaller of the two numbers. The calculator gives you the risk-based number; the cap is your own line in the sand.
A stop-loss order doesn't fix your exit price. If a stock opens below your stop, the order fills at the next available price. Keep that in mind when a stop sits very close to the entry.
Why 1% matters over a losing streak
Every trader has runs of losses. The percentage you risk decides how deep the hole gets. The table below risks the same percentage of the remaining capital on each trade — simple arithmetic, not a forecast.
| Risk per trade | Capital left after 5 losses | Capital left after 10 losses |
|---|---|---|
| 1% | About 95% | About 90% |
| 3% | About 86% | About 74% |
| 5% | About 77% | About 60% |
At 1%, ten losses in a row is a bad month. At 5%, it is 40% of your account gone, and you now need a much bigger gain just to get back to where you started. Small risk keeps you in the game long enough to learn.
Charges and small trades
In Indian cash delivery trades you pay brokerage (with some brokers), STT, exchange charges, stamp duty, GST and DP charges when you sell. On a large position these are small next to your risk. On a tiny position they can be a big slice of it.
If you risk ₹200 on a trade and then pay round-trip charges on top, your real loss when the stop hits is bigger than planned. Check your broker's charge calculator for a real number, and if charges eat a large part of your risk, the trade may be too small to be worth taking.
A quick checklist before you buy
- 1Mark the stop-loss on the chart, at the price where your idea is wrong.
- 2Decide your risk in rupees: capital × risk %.
- 3Divide by the risk per share and round down.
- 4Check the position value against your cash and your cap per stock. Take the smaller number.
- 5Check the reward with the risk-reward calculator. If the nearest real target is too close, skip it.
- 6Place the stop-loss order (or a GTT order) as soon as you are in.
Why the stop comes first
The stop-loss belongs where the chart says your idea is wrong — under a swing low or a demand zone. If you move it closer just to buy more shares, normal daily movement can knock you out of a good trade. If you move it further to feel safe, you lose more when you're wrong.
So find the stop on the chart first, then let the size follow. The lesson on setting a stop-loss shows four ways to place it.
Common sizing mistakes
- Sizing by conviction: buying more because you feel sure. The chart doesn't know how you feel.
- Risking more after a loss to win it back quickly. Losing streaks are normal; bigger bets make them dangerous.
- Buying with borrowed money without changing the maths. Margin makes the same price move cost more.
- Forgetting charges and gaps. A stock can open below your stop, so the real loss can be a little bigger.
- Measuring risk on the whole position instead of the stop distance. Buying ₹10,000 of a stock does not mean you risk ₹10,000; you risk the shares × (entry − stop).
- Using a fixed number of shares for every trade. 100 shares of a ₹50 stock and 100 shares of a ₹2,000 stock carry very different risk.
Once the size is right, check the trade is worth taking with the risk-reward calculator.
Quick check
Key terms
- Position size
- The number of shares you buy in one trade.
- Risk per trade
- The most you're willing to lose on one trade, often written as a percentage of capital.
- Risk per share
- Entry price minus stop-loss.
- Position value
- Shares × entry price: what the trade costs to buy.
Common questions
How do I calculate position size for a stock?
Multiply your capital by the percentage you'll risk, then divide by the gap between your entry and your stop-loss. Round down. That's the number of shares.
What percentage of my capital should I risk per trade?
Many traders risk 1% or less of their capital on one trade, so a run of losses stays survivable. Pick a number you could stick to through ten losses in a row.
Does this work for intraday or F&O trades?
The formula works for any trade with a stop-loss. In F&O you size in lots, and leverage makes losses grow faster. This calculator is built for buying stocks.
Are charges included?
No. Brokerage, STT and other charges, plus slippage on gaps, can make a loss a little bigger than the number shown.
What if the calculator says I should buy more than I can afford?
Buy what you can pay for in cash, or what your cap per stock allows, whichever is smaller. You'll be risking less than planned, which is fine. Don't use margin just to reach the number.
Should I use my starting capital or my current capital?
Your current capital. After losses, your rupee risk shrinks with the account; after gains, it grows slowly. Many traders update the number once a week or once a month to keep it simple.
Is 2% risk per trade too much?
It depends on you, but 2% doubles every loss compared with 1%. Beginners often start at 1% or less while they learn, and only raise it once their process is steady.
Kitne shares khareedne chahiye?
Pehle tay kariye ki ek trade mein kitna loss chal sakta hai, jaise capital ka 1%. Phir use entry aur stop-loss ke beech ke farak se divide kariye. Wahi aapke shares hain.
Keep going
Education only — not investment advice. Trading in the stock market carries risk. Charts on this page use made-up prices for practice — they are not real stocks or recommendations. Examples are for learning only.