Paid calculator
Black-Scholes option calculator
Price a European call and put and see delta, gamma, vega and theta. Useful for valuing employee or founder options and for learning how options behave.
Paid calculator
Black-Scholes option calculator
Buy this calculator on its own for $9, one time. No membership needed. It runs in your browser and nothing you enter is sent to us or saved. Read how it works and the questions below first.
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How it works
How it works
The Black-Scholes model values a European option from the current price, strike, time to expiry, risk-free rate and volatility, with no dividends. d1 = [ln(S/K) + (r + vol^2/2) x t] / (vol x sqrt t), d2 = d1 - vol x sqrt t, and call = S x N(d1) - K x e^(-rt) x N(d2). Real options can be priced differently, so this is an estimate.
FAQ
About this calculator
Does this give investment advice?
No. It is a textbook model for general information and learning. It is not a recommendation to buy or sell anything.
What does it leave out?
Dividends, early exercise on American options and real-world pricing frictions. Volatility is also an estimate.
What is delta?
How much the option value moves for a $1 move in the asset, roughly. Gamma is how fast delta changes.
Is anything saved?
No. The math runs in your browser and nothing you enter is sent to us.
Is this tax or financial advice?
No. It is a calculator for general information. Check the numbers against your own records, and ask an accountant before you act on them.
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