Not financial advice. Options involve risk and are not suitable for all investors. Data is delayed up to 15 minutes.
Transparent by design
PayoffPlot separates observed market inputs from modelled estimates. This page documents the rules used by the calculator and finder so results can be interpreted and reproduced.
Equity quotes come from Alpaca. Option contracts, bid/ask prices, last trades, implied volatility, Greeks, volume, and open interest come from Massive. Provider labels and the response timestamp are shown in the calculator; provider identity alone does not mean that a quote is real-time.
A manually edited premium, including a premium restored from a legacy shared URL, is not overwritten when the global quote basis changes.
At expiration, a call's intrinsic value is max(stock price − strike, 0); a put's is max(strike − stock price, 0). Long-leg profit is intrinsic value minus premium, while a short leg reverses that cash flow. Each result is multiplied by contract quantity and the standard 100-share option multiplier. Stock legs use quantity × (future price − entry price), with the sign reversed for short shares.
Estimated commission = option contracts × commission per contract per side × charged sides. Opening-only calculations use one side; enabling the closing estimate uses two. Commission is subtracted once from every position outcome and from expected profit. It does not alter Greeks.
Before expiration, European option values are estimated with Black–Scholes–Merton using the scenario stock price, strike, time remaining, each contract's implied volatility, and a 5% annual risk-free rate. The IV control scales each leg's observed IV. Delta, gamma, theta, vega, and rho are calculated per leg and signed by buy/sell direction and quantity before aggregation.
The current model does not include discrete dividends, borrow costs, volatility skew changes, early exercise, or American-style numerical pricing.
Probability of profit integrates a risk-neutral lognormal terminal-price distribution over the profitable expiration ranges implied by the calculated breakevens. Expected value applies the same distribution to the full expiration payoff curve. These are model estimates, not a forecast of actual returns or the probability assigned by the market.
The 100-point score combines relative bid–ask spread (50 points), open interest (30), and volume (20). Grades are A at 80+, B at 65+, C at 45+, D at 25+, and F below 25. Crossed or invalid markets and zero-bid contracts score zero. Warnings identify wide spreads, low open interest, and absent volume. Multi-leg finder grades are quantity-weighted averages; liquidity breaks ties after the selected optimization score.
Use the results for education and scenario analysis, not as financial advice. Return to the options calculator to inspect the active assumptions beside your trade.