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Black-Scholes option calculator

Pick a stock and price a European call and put with all the Greeks — the price, volatility, dividend and interest rate fill themselves in.

Market inputs — editable

Once you pick a ticker these fill themselves from the price history (last year's volatility, the trailing 12-month dividend, the central-bank rate for the stock's currency). You can overwrite them.

Call price 📈1.17
Put price 📉5.82
GreekCallPutWhat it says
Delta0.275-0.725 How much the option moves when the stock moves by 1.
Gamma0.04650.0465 How much delta itself changes per 1 move in the stock (how fast it "accelerates").
Vega0.0960.096 Price change when volatility rises by 1 percentage point.
Theta-0.043-0.031 How much the option loses each day just from time passing ⏳.
Rho0.022-0.064 Price change when interest rates rise by 1 percentage point.

d1 = -0.5990 · d2 = -0.6707

In plain words 💡

A call option is the right, not the obligation, to buy a stock at the strike price on expiry day. A put is the right to sell it. Black-Scholes answers one question: what is that right worth today, if the stock price wanders randomly with a given volatility.

Volatility does most of the work 🎢: the more the stock can swing, the more the right is worth, because an option's upside is open-ended while the loss stops at the price paid. Time works the other way — every day eats a little of the value (theta).

Where the formula is wrong ⚠️

It assumes constant volatility, continuous trading and no price jumps. With a ticker picked we use last year's historical volatility, while the market prices options with implied volatility — a different one for every strike (the volatility smile). So the result is a textbook price, not an exchange quote. The model is for European options (exercise only on expiry day).

Read more 📚

An educational tool: it runs a formula on historical data or on the numbers you type. It is not a forecast or a recommendation, and it knows nothing about your situation.