Two-leg payoff at expiration
Option Debit Spread Calculator
Calculate profit or loss, net debit, break-even, maximum profit, maximum loss and return on risk for a bull call or bear put debit spread.
Debit spread results
Expiration-only model: this calculator does not estimate the spread value before expiration, assignment timing, volatility, Greeks or early exercise.
| Underlying at expiration | Long-leg payoff | Short-leg payoff | Gross spread P/L | Net P/L after fees |
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How the option debit spread calculation works
A debit spread buys one option and sells another option of the same type with the same expiration. The long option costs more than the premium collected from the short option. The short leg lowers the entry cost and caps the gain, while the net debit limits the loss.
Gross debit per share: bought premium − sold premium.
Maximum loss: gross debit × shares + fees.
Maximum profit: (strike width − gross debit) × shares − fees.
Bull call break-even: bought call strike + net debit per share.
Bear put break-even: bought put strike − net debit per share.
For a bull call spread, the long call has the lower strike and the short call has the higher strike. For a bear put spread, the long put has the higher strike and the short put has the lower strike. Net debit per share includes fees allocated across all covered shares.
Verified bull call example
Buy two 100-strike calls for $6 per share and sell two 110-strike calls for $2 per share, with 100 shares per contract and $4 of total fees. The gross debit is $800, net debit and maximum loss are $804, maximum profit is $1,196 and break-even is $104.02. At an expiration price of $115, the spread reaches its full $10 width and net profit is $1,196.
Verified bear put example
Buy one 110-strike put for $7 and sell one 100-strike put for $3, with a 100-share multiplier and $2 of fees. Gross debit is $400, maximum loss is $402, maximum profit is $598 and break-even is $105.98. At an expiration price of $95, both puts are in the money, the spread reaches its full $10 width and net profit is $598.
Limits and assumptions
The model assumes both legs have the same expiration and multiplier, remain open through expiration and settle from intrinsic value. Premiums are entered per share. It excludes bid-ask spreads, slippage, taxes, margin changes, dividends, exercise and assignment before expiration, pin risk, interest, volatility and broker-specific rules. The simple annualized return multiplies one-period return by 365 divided by days; it is not a forecast and assumes the same risk could be repeated continuously.
Options can create rapid losses. Confirm contract specifications, buying-power requirements, expiration procedures and fees with the broker. This educational calculator is not investment, tax or legal advice.
Related calculators
- Option Credit Spread Calculator — model bull put and bear call credit spreads.
- Options Profit Calculator — model one long or short call or put.
- Calendar Spread Calculator — model same-strike options with different expirations.
- Black-Scholes Calculator — estimate European option value and Greeks before expiration.