Position Size Calculator (Risk-Based)
Calculate share quantity to buy based on account risk percentage and stop-loss distance.
Formula and method
This calculator computes Shares to buy directly in your browser without sending data to an external server.
Mathematical formula
- Shares to buy:
entryPrice===stopPrice ? NaN : Math.floor((accountSize × (riskPct ÷ 100)) ÷ |entryPrice-stopPrice|)
Variables and parameters
- Account size (accountSize): default value 10000.
- Risk per trade (riskPct): default value 1 %.
- Entry price (entryPrice): default value 50.
- Stop-loss price (stopPrice): default value 47.
Some formulas are undefined for certain input combinations (such as division by zero or logarithms of non-positive numbers). In those cases the live tool displays an alert instead of NaN.
Embed this tool
Paste this snippet into your own site or blog post to embed a live, working copy of this tool. It links back to the full page on SpecWhale.
Frequently asked questions
What equation and variables does Position Size Calculator (Risk-Based) use?
Position Size Calculator (Risk-Based) evaluates outputs such as <strong>Shares to buy</strong> based on inputs including Account size, Risk per trade, Entry price, Stop-loss price. Check the Mathematical Method section for the explicit formula.
How can I compare different financial scenarios using Position Size Calculator (Risk-Based)?
You can click the "Add to Compare" button after computing your scenario to pin it to your temporary side-by-side Compare Workbench, allowing you to evaluate loan, rate, or interest differences.
What happens if I enter invalid or zero values into Position Size Calculator (Risk-Based)?
If an input combination is mathematically undefined (such as division by zero or negative square roots), SpecWhale alerts you gracefully rather than returning invalid NaN outputs.
Are my calculations in Position Size Calculator (Risk-Based) saved or private?
All calculations are 100% private and run locally in your Web browser. Your numbers are never uploaded to any server, but can be saved locally to your device or exported as CSV/JSON.
Is Position Size Calculator (Risk-Based) free to use?
Yes. Position Size Calculator (Risk-Based) is completely free, has no usage limit, and does not require an account, email, or API key.
Does Position Size Calculator (Risk-Based) store or upload my data?
No. Position Size Calculator (Risk-Based) calculates everything locally in your browser. Nothing you type is sent to a server or stored by SpecWhale.
How accurate is Position Size Calculator (Risk-Based)?
Position Size Calculator (Risk-Based) uses a standard formula (see the Method section above for the exact expression). For high-stakes financial, medical, or legal decisions, confirm the result with a professional or an authoritative source before relying on it.
Can I embed Position Size Calculator (Risk-Based) on my own website?
Yes. Use the "Embed this tool" snippet on this page to add a free, working copy of Position Size Calculator (Risk-Based) to your own blog post or page.