How to use this calculator
- Enter underlying spot price, strike, continuous risk-free rate (%), continuous dividend yield (%), years to expiry, observed call price.
- Choose a display currency, then select Calculate. Results also update after a brief pause while you edit.
- Read the result with the assumptions below. Export details or save a second scenario to compare your choices.
Formula and method
Assumptions and limitations
Same strike and expiry, frictionless markets; American exercise and discrete dividends require different treatment. Negative result signals inconsistent inputs.
Worked example
With underlying spot price = 100, strike = 100, continuous risk-free rate (%) = 0, continuous dividend yield (%) = 0, years to expiry = 1, observed call price = 10, parity-implied put price is approximately 10.
What the result means
Infer a corresponding European put value from a matched call under a continuous-yield model.
Common questions
How should I interpret parity-implied put price?
Infer a corresponding European put value from a matched call under a continuous-yield model.
What should I check before using this result?
Same strike and expiry, frictionless markets; American exercise and discrete dividends require different treatment. Negative result signals inconsistent inputs.
Methodology and transparency
Calculation specification reviewed on 2026-10-14. Mathematical implementation is tested against independent reference fixtures. This does not imply review by a licensed financial professional. Read the testing and precision policy.
Background reference: www.optionseducation.org — financial method. FinanceMath implements its own calculator.