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OPTIONS / LEARNING LABORATORY

Compare a call
or put spread.

Explore how much a two-option position could gain or lose at expiration. Enter the contracts and prices yourself, or start with the fictional example.

Manual assumptions · USD · Four vertical strategies

Entries stay in this calculator; there is no automatic save.
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01 / DEFINE THE SCENARIO

Enter the two options.

New to the terms?

A spread combines an option you buy (the long leg) and one you sell (the short leg). A call is an option to buy; a put is an option to sell. The strike is the contract’s exercise price, and the premium is the option’s price per underlying unit. A debit spread costs money to open; a credit spread receives money to open, before fees.

“Bull” describes a rising-price view; “bear” describes a falling-price view. This tool calculates outcomes, not whether a strategy is suitable for you.

One long option and one short option per spread, for the same underlying and expiry. Use decimal amounts with at most two places, without commas. Enter known zero fees explicitly. This model excludes ratio, calendar and adjusted-deliverable spreads.

03 / COMPARE OUTCOMES

Compare possible ending prices.

The table holds the premiums and fees fixed. It is an expiration payoff illustration, not a price forecast or the value of an option before expiration.

Calculate a scenario to populate the table.

04 / CONNECT THE FINDINGS

A payoff is not an investment case.

This laboratory does not collect evidence or recommend a trade. Use these questions to identify what is still missing from an actual research review.

Questions for researching an actual trade

What supports the view?

Record the business thesis, contrary evidence, dated filings and valuation assumptions. Explain why the chosen price range and time horizon follow from those findings; identify what would invalidate them.

What could happen first?

Check earnings, corporate actions, the ex-dividend date and other dated events. The same expiration payoff can conceal very different interim paths, financing needs and assignment exposure.

Are the legs executable?

Verify the actual contract deliverable, multiplier, exercise/settlement terms, current bid/ask quotes, quote times, liquidity and all fees. Entered premiums are assumptions; this tool has not checked any of them.

DTP findings-based options recommendations remain a separate development item. No current opportunity, probability of profit or personal suitability is established here.

KEEP THE LIMITS WITH THE NUMBERS

Before relying on a spread diagram.

Why a bounded diagram is not the whole risk

The displayed bounds assume equal quantities of the same option type, underlying and expiry, with both legs fully settled together at intrinsic value. They exclude slippage, taxes, financing and changes to the positions. A leg closed separately, a short option assigned before the long leg is exercised, or a missed exercise deadline can leave stock exposure and financing needs outside that simplified payoff.

Assignment, dividends and expiration

An American-style short option can be assigned before expiration. A protective long option does not automatically exercise merely because the short option was assigned. Call assignment risk can increase around an ex-dividend date. Near a strike at expiry, price changes and exercise decisions can leave one leg exercised and the other unexercised. Verify the contract terms, broker deadlines and account obligations; this model does not simulate that path.

How fees and break-even are shown

Premiums are per underlying unit, multiplied by the entered contract count and multiplier for each leg. Enter one total fee estimate for the entire position, including any assumed exit or exercise charges; it is deducted once. The result does not separately estimate those charges. Break-even is shown to four decimal places and can fall between quoted price increments. If fees consume all gross profit, a zero-P&L plateau is shown; if fees exceed it, no profitable or break-even expiration price exists under these assumptions.

Scope, sources and data

Educational scenario arithmetic, not personalized investment, financial or tax advice. Positive expiration P&L does not establish that an option can be bought at the entered premium or that the outcome is likely. Supported input amounts are up to $10 million, whole contract counts/multipliers up to 10,000 and total strike-width exposure plus fees up to $10 billion. Inputs are calculated locally; no analytics library or browser storage is used by this tool.

Sources reviewed October 23, 2026: FINRA: understanding options assignment; OCC: Characteristics and Risks of Standardized Options. Read the current disclosure and actual broker/contract rules before considering options.