How it works

Every strategy has its own page rather than sharing one calculator behind a dropdown. Pick the one you are considering from the strategies list, and the page opens with the right number of legs, in the right directions, at sensible strikes. If you already know what you want, the URL is predictable: /calculator/iron-condor, /calculator/covered-call, and so on.

If you are not sure which strategy fits, two other routes exist. The Option Finder takes a price target and a budget and searches for positions that fit. The comparison page puts two to four strategies side by side on identical assumptions.

The form is ordered by how much each field changes the answer.

1. The stock price. Everything is measured against it. Type the price you are actually looking at.
2. Each leg: strike, premium, expiration, contracts. The premium is the per-share price, the way it is quoted — 4.20, not 420. The calculator handles the multiplier.
3. A target price, optionally. Setting one adds a marker to the chart and a profit-at-target figure to the summary.
4. Advanced assumptions, collapsed by default: interest rate, dividend yield, commissions, fees and slippage. The defaults are reasonable, and most people never open this. Open it if you trade size, where commissions genuinely move breakevens.

Beside numbers on this site you will see a small badge. It exists because a calculator that mixes your inputs with its own guesses, and does not say which is which, is dangerous.

Yours

You typed it. The calculator treats it as fact.

Market

It came from a market data feed, with a timestamp. See the market data disclosure for what is live and what is delayed.

Model

A pricing model produced it from other inputs. It is a theoretical value, not a price anybody quoted, and not a price you can necessarily trade at.

Default

A placeholder the page started with so nothing is blank. Replace it before drawing any conclusions.

The banner above the results tells you which mode the whole page is in. A single model-priced premium is enough to make the entire result theoretical, and the banner says so rather than letting a mixed result pass as a real one.

The horizontal axis is the price of the underlying. The vertical axis is your profit or loss in dollars. The solid line is the exact payoff at expiration — green where you make money, red where you lose it.

Four kinds of vertical marker appear on it:

• Breakeven lines, where the payoff crosses zero. This is the price the stock has to reach for you to have broken even, and it is not the same as the strike.
• Current price, so you can see how far the position has to travel.
• Strikes, which are where the payoff changes direction.
• Your target, if you set one.

Hovering or moving the arrow keys along the chart reads out the profit at each price. The whole curve is also available to screen readers as a table, so nothing on this page is locked behind a picture.

These are the most useful controls on the page and the most often ignored. The solid line shows expiration. The sliders show you everything before it.

The date slider

Drag it and a dashed line appears: what the position is worth on that date, estimated by the pricing model. The gap between the dashed line and the solid one is time value — the part that drains away whether or not the stock moves. Long option buyers should look at this before entering; it is the clearest available picture of what you are fighting.

The volatility slider

Shifts every leg’s implied volatility up or down by a number of points. This is how you test the scenario that catches people out: the stock moves your way, but volatility collapses, and the position loses money anyway. Drop volatility 10 points on a long call bought before earnings and you will see the mechanism that produces most post-earnings complaints.

The chart shows one date at a time. The table shows every combination of price and date at once, which is a different and sometimes better way to see a position. The last column is expiration, and it is exact. Every other column is a model estimate.

The output switcher changes what each cell means:

• Profit and loss in dollars — the default, and what most people want.
• Percent of entry cost — return on what you put in.
• Percent of maximum risk — return against what you could lose, which is the more honest comparison between strategies.
• Estimated position value — what the position itself would be worth, rather than your gain on it.

Read these in a specific order, because two of them can make the rest irrelevant.

1. Maximum loss. First, always. If it says Unlimited, nothing else on the page matters until you understand why. The calculator will never show a large finite number in place of an unbounded risk.
2. Maximum profit. Against the maximum loss, this gives you the shape of the bet.
3. Breakevens. Where the stock has to get to. Compare this against where it is now and ask whether the move is plausible in the time available.
4. Chance of profit. A model estimate with its assumptions stated beside it. Treat it as a rough guide, and read the limitations before leaning on it.
5. Greeks. Delta in share equivalents, theta per calendar day, vega per volatility point.

Copy share link puts the whole position into a URL. Anyone who opens it sees exactly what you see. Nothing is stored on a server, and the link keeps working indefinitely because the position travels inside it.

Save stores the calculation in this browser, on this device. It is private, it is not tied to an account, and it will not appear on your phone. Clearing your browser’s site data deletes it. If you want a calculation to survive, use the link.