Risk & Positioning · MANUAL INPUT
Options Position Size Calculator
Convert an account risk budget into a whole-contract position limit.
How to use this tool
A position unit can mean one option contract or one complete spread. Enter the maximum loss for that entire unit, including expected fees. The result rounds down, never up.
Capital requirement is a separate input because margin, debit and maximum loss can differ. A stop price is not a guaranteed maximum loss, and this tool is inappropriate for unlimited-risk trades without a separate risk limit.
Worked example
A $25,000 account with 1% risk allows $250 of risk. At $200 maximum loss per spread, the limit is one spread.
Related tools
Model references and conventions
365 calendar days per year. Continuous rates for theoretical pricing. All examples are illustrative.