Tools
Position Size Calculator — how many shares should I buy?
Calculate shares from your account size, risk percentage, entry, and stop-loss. For planning only — not financial advice.
Quick answer
Divide your dollar risk (account × risk %) by the per-share risk (|entry − stop|). Example: $10,000 account, 1% risk ($100), $3 stop distance → about 33 shares. One stop-out should not blow up the portfolio.
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Definition
Position size (shares) = (Account × Risk %) ÷ |Entry − Stop|
Result
Enter values and tap “Calculate position size” to see shares and notional size.
When should you use it?
- •Different stocks and prices — same % risk per trade.
- •Building a portfolio with several positions.
- •Learning risk management before sizing up.
How it works
- 1
Set your risk
Pick the % of your account you are willing to lose if this trade stops out.
- 2
Define the trade
Enter planned entry and the stop price you will actually honor.
- 3
Get your size
We divide dollar risk by per-share risk to get share count.
Example
Scenario: $25,000 account, risk 2% per trade. Buy NVDA at $130.00 with stop at $124.00.
Math: Risk = $25,000 × 2% = $500. Per-share risk = $6. Shares = $500 ÷ $6 ≈ 83.3 → 83 whole shares.
Result: Notional ≈ $10,790 at entry. If the stop fills near $124, loss is about $498 (under 2% of the account).
Frequently asked questions
Position sizing is choosing how many shares (or contracts) to trade so that if your stop-loss is hit, you only lose the dollar amount you planned — usually a small fixed percentage of your account.
Quick reference table
| Risk % | Account | Risk $ | Stop distance | Shares |
|---|---|---|---|---|
| 1% | $10,000 | $100 | $3.00 | 33 |
| 1% | $25,000 | $250 | $5.00 | 50 |
| 2% | $10,000 | $200 | $2.00 | 100 |
| 2% | $50,000 | $1,000 | $10.00 | 100 |
| 0.5% | $100,000 | $500 | $4.00 | 125 |
Many professionals keep per-trade risk near 0.5%–2% of equity. Consistent sizing is one part of surviving long enough for edge to show up — it is not a guarantee of profitability.
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Last updated: April 2026
FX13: AI Trading Signals offers free calculators and educational pages for traders and investors. Nothing here is personalized investment advice. Trading involves risk of loss. © 2026 Rakhimboy Rozmetov. FX13: AI Trading Signals
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