Position Size Calculator
Calculate the optimal position size based on your account size, risk percentage, and stop loss distance. Essential for proper risk management.
Educational use only. Not financial advice. Results are estimates. Trading involves risk. Read full disclaimer.
Position sizing is one of the most critical aspects of risk management in trading. This calculator helps you determine exactly how many shares, contracts, or units to trade based on your account size and the amount you're willing to risk per trade. By using consistent position sizing, you protect your capital and ensure that no single trade can significantly damage your account.
Position Size Calculator
Results
Dollar Risk
$100.00
Risk Per Unit
$5.00
Position Size
20 units
Position Value
$2,000.00
Estimates only.
How to Use This Calculator
- Enter your account size: Your total trading capital or account balance.
- Set your risk per trade: The percentage of your account you're willing to risk (typically 1-2%).
- Enter your entry price: The price at which you plan to enter the trade.
- Enter your stop loss price: The price at which you'll exit if the trade moves against you.
- Optional: Add commissions/fees: Enter any trading fees or commissions for this trade.
- Review the results: The calculator shows your dollar risk, risk per unit, position size, and total position value.
Formula
Dollar Risk = Account Size × (Risk % ÷ 100)
Risk Per Unit = |Entry Price - Stop Loss Price|
Available Risk = Dollar Risk - Commissions/Fees
Position Size = Floor(Available Risk ÷ Risk Per Unit)
Common Mistakes to Avoid
- Risking too much per trade: Many traders risk 5% or more, which can lead to account destruction. Stick to 1-2% maximum.
- Ignoring commissions: High-frequency traders especially need to account for fees, as they can significantly impact profitability.
- Not adjusting for volatility: If your stop loss is too tight for the asset's volatility, you'll get stopped out frequently. Ensure your stop is based on technical analysis, not arbitrary percentages.
- Inconsistent position sizing: Changing your risk percentage from trade to trade defeats the purpose. Pick a percentage and stick with it.