Options Profit Calculator.
P&L by Share Price and Time.

For a buyer: (price you sell the option for − premium you paid) × 100 × number of contracts, minus commissions. A standard US equity option covers 100 shares, and premiums are quoted per share. Example: buy one call at $2.50 ($250 in total) and sell it later at $6.00 ($600): profit = ($6.00 − $2.50) × 100 = $350. For a seller the signs reverse: you keep the premium received minus what it costs to buy the option back. The heatmap shows this P&L for one contract, before commissions.

It is a table of profit or loss for one position. In this calculator each row is a share price, from 15% below to 15% above the price you enter with the highest at the top, and each column is a date: today, one-third and two-thirds of the way to expiry, and expiry. Green cells are profits, red cells are losses, and darker shading means a larger amount. Reading across a row shows what time alone does to the position at that price.

Time decay (theta) reduces an option's time value as expiry approaches, and the decline speeds up near expiry. For option buyers it is a cost: if the share price does not move enough, the option loses value anyway. For option sellers it works in their favour. In the worked example on this page, a long $105 call shows +$12 today with the stock at $105 but −$105 with ten days left, at the same share price.

At expiry, a call breaks even at strike price + premium and a put at strike price − premium. If you buy a $105 call for $2.50, you break even at $107.50 at expiry and profit above it. The heatmap does not print the break-even, but its expiry column moves from −$250 at $105 to +$250 at $110, which brackets $107.50. Before expiry the break-even price is different, because the option still has time value.

It values the option with the Black-Scholes model using the implied volatility you enter, a fixed 5% risk-free rate and no dividends, and holds implied volatility constant across the grid. It shows one contract of 100 shares and leaves out commissions and early exercise. Real option prices also move with changes in implied volatility, so treat the grid as an estimate.