Debit & Credit Spread Expectancy Calculator
Compare modeled vertical-spread outcomes, then use your own trading results to calculate historical expectancy.
What this mode assumes: Every winning trade realizes maximum profit and every losing trade realizes maximum loss. “Assumed win rate” may be estimated from probability of profit, but POP is not necessarily the probability of earning maximum profit.
Shared Assumptions
Historical win rate is preferable when enough relevant trades are available.
Optional. Enter the total cost to open and close one complete spread.
Why the Two Modes Differ
A vertical spread can finish at maximum profit, maximum loss, or anywhere between them. The theoretical mode simplifies that range into two outcomes. The historical mode uses your average realized winner and loser, capturing early exits, partial outcomes, slippage, and trade management.
Debit Spread
Credit Spread
The result is a simplified model, not a forecast or trading recommendation. Prices are entered per share; dollar results use the standard 100-share option multiplier. Assignment, exercise, slippage, taxes, and partial outcomes are not modeled separately.
Use actual closed-trade data when available. Enter average net winner and average net loser after commissions and fees. This mode measures the outcomes your system has actually produced rather than assuming maximum profit and maximum loss.
Historical Results
Historical expectancy describes the selected sample only. Results may change as market conditions, execution quality, position sizing, and trade management change. A small sample may not be representative.