How to use this options calculator
- Pick a strategy. The legs are filled in automatically around the current stock price.
- Enter the stock price, implied volatility (IV) and days to expiration. You can find IV on your broker's option chain.
- Adjust strikes and replace the theoretical prices with the real bid/ask you see at your broker.
- Read the chart: the solid line is your profit or loss at expiration; the dashed line shows the estimated P/L on any date before expiry (move the slider).
Covered call calculator
A covered call means you own 100 shares and sell one call option against them. You receive the premium immediately. If the stock ends above the strike at expiration, your shares are sold at the strike price and your profit is capped. If it ends below, you keep the shares and the premium cushions any loss.
The calculator shows three numbers that matter for covered call sellers:
- Return if called = (premium + strike − stock price) ÷ stock price. This is your best-case return.
- Return if unchanged = premium ÷ stock price, the return if the stock doesn't move.
- Annualized return = return × 365 ÷ days to expiry, useful to compare trades with different expirations.
Cash-secured put calculator
Selling a cash-secured put means you agree to buy 100 shares at the strike price and keep enough cash to do it. You collect the premium up front. If the stock stays above the strike you keep the premium; if it falls below, you are assigned and buy the shares at an effective price of strike minus premium. Many investors combine cash-secured puts and covered calls in what is called the wheel strategy.
What the Greeks mean
- Delta: how many dollars the position gains when the stock rises $1, shown as equivalent shares.
- Gamma: how fast delta changes when the stock moves.
- Theta: how much the position gains or loses per day from time decay. Option sellers usually have positive theta.
- Vega: how much the position changes for each 1 percentage point change in implied volatility.
Frequently asked questions
How is the probability of profit calculated?
The stock price at expiration is modeled as lognormal, using the implied volatility you entered. The calculator adds up the probability of every price at which the strategy finishes with a profit. It is an estimate, not a guarantee.
Are the option prices real market quotes?
No. They are theoretical Black-Scholes values from your inputs. For exact results, type the real prices from your broker into the Price column.
Does this include commissions and taxes?
No. Results are before commissions, fees and taxes. American-style early assignment is not modeled.
Is my data sent anywhere?
No. Everything runs in your browser. The share link only stores your inputs in the URL.
For educational purposes only. Not financial advice. Options involve risk and are not suitable for all investors.