Trading Tool
Position Size Calculator
Calculate position size based on capital risk and stop loss.
About This Tool
Position Size Calculator helps you calculate trade quantity from capital risk and stop loss distance. It is designed for trading risk and position planning and keeps the calculation simple enough to compare scenarios without confusion.
Use this calculator when you want a quick view of position size, capital at risk, position value before making a money decision. The result updates in your browser, so you can test different assumptions without reloading the page.
How to Use This Calculator
- Enter the values that match your real situation, not just ideal numbers.
- Review the main result first, then look at the supporting figures and chart where available.
- Change one input at a time so you can see what actually moves the result.
- Compare at least two scenarios, such as conservative and optimistic assumptions.
How the Calculation Works
The calculator divides the amount you are willing to risk by the risk per unit.
It starts with how much capital you are willing to risk, then divides it by the risk per unit.
Formula Used
Position Size = Capital at Risk / Absolute difference between Entry and Stop Loss.
Input Field Explanation
Trading Capital
Enter the trading or investment capital available for this calculation.
Risk Per Trade (%)
Enter the percentage of capital you are willing to risk on the trade.
Entry Price
Enter the planned trade entry price.
Stop Loss
Enter the stop loss price used to measure trade risk.
Example Calculation
For example, if you can risk 5,000 and risk per share is 5, the position size is 1,000 shares.
If capital risk is 5,000 and risk per share is 5, the position size is 1,000 shares. Replace the sample values with your own numbers before using the estimate for planning.
Benefits of Using This Tool
- Helps prevent oversized trades.
- Connects stop loss with quantity.
- Keeps risk consistent across trades.
- It helps you check risk, reward and charges before entering a trade.
Common Mistakes to Avoid
- Choosing quantity first and risk later.
- Ignoring gap risk or slippage.
- Using too high a risk percentage.
- Do not increase quantity without checking the money at risk.
- Do not treat the estimate as a guaranteed final outcome.
Things to Consider
- Actual execution price can differ.
- Liquidity matters for larger positions.
- Risk should fit your account size and experience.
- Trading has market risk, slippage and costs that can change the final outcome.
- Confirm important numbers with official documents or a qualified professional when needed.
Frequently Asked Questions (FAQ)
Why calculate position size?
It helps align quantity with the money you are willing to risk.
Can position sizing stop losses?
No. It can control planned risk, but losses can still happen.
Is the Position Size Calculator free to use?
Yes. You can use it free on The Market Side Tools without creating an account.
What does the Position Size Calculator calculate?
It calculates position size, capital at risk, position value based on the values you enter.
Does this tool save my data?
Values entered into this calculator are processed in your browser for quick estimates.
How accurate is the result?
The math follows the formula, but real-world results can differ because rates, taxes, fees and timing can change.
Can I use the default values?
The default values are only examples. Replace them with your own numbers before relying on the estimate.
Can this calculator help compare scenarios?
Yes. Change one value at a time to compare different rates, amounts or time periods.
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Educational Disclaimer
The Position Size Calculator is for education and planning only. This tool does not provide buy, sell or hold recommendations. Always verify important numbers before taking action.