SPREADVECTOR
Start free trial ›
Free tools

Credit Spread Calculator

Bull put or bear call: enter the strikes and the credit. See the most you can make, the most you can lose, your breakeven, and the chance of profit.

Free, no sign-up. Bookmark this page to come back to it.

Spread type
Your trade (example numbers; replace them with yours)
Max profit
$120.00
Credit × 100 × 1 contract
Max loss
−$380.00
(Width − credit) × 100 per contract
Return on risk
31.6%
Max profit ÷ max loss, for this trade
Breakeven at expiration
$93.80
Short strike − credit
Spread width
$5.00
Distance between the strikes
Credit as % of width
24.0%
Higher means more paid for the risk
Chance of profit at expiry
80%
Model estimate: stock above breakeven
Chance of keeping it all
75%
Model estimate: stock above the short strike

Margin: most brokers hold the max loss, $380, as buying power for this spread. The most you can lose is fixed before you enter.

Want this across every stock?

This calculator checks one trade you already found. SpreadVector's screener runs spread math like this across 800+ stocks with weekly options and ranks the setups. Your first scans are free, with no card needed.

Run a free scan →or get the weekly scan by email ↓

How the numbers are worked out

Max profit is the net credit you collect, kept in full if the stock finishes beyond the short strike. Max loss is the width between the strikes minus that credit. The bought option caps it, so it's known before you enter.

Breakeven is the short strike minus the credit for a bull put spread, or plus the credit for a bear call spread. Return on risk is max profit divided by max loss for this one trade.

The chances are Black-Scholes model estimates at the implied volatility you enter: the chance the stock finishes past breakeven (a profit at expiration) and past the short strike (the full credit kept). They don't account for earnings, news or early assignment.

Questions

What's the difference between a bull put and a bear call spread?
A bull put spread sells a put below the stock price and buys a lower one for protection. It profits if the stock stays above the short strike. A bear call spread sells a call above the price and buys a higher one, and profits if the stock stays below the short strike.
What does credit as a percent of width tell me?
How much you're paid relative to what you risk. A $1.00 credit on a $5-wide spread is 20%: you risk $4 to make $1. Higher percentages pay more, but usually come with short strikes closer to the stock price.
Why isn't there an annualized return?
Annualizing a single short-dated spread multiplies a one-month result by twelve or more, which produces very large numbers that are rarely achieved in practice. Return on risk for the trade itself is the more honest figure.
Which implied volatility should I enter?
The implied volatility of the short strike, from your broker's option chain. It's used only for the probability estimates; every other figure works without it.

More free calculators

Cash-secured put calculator →Wheel strategy calculator →
⚠These calculators use only the numbers you enter; no market data is looked up. Probabilities are estimates from the Black-Scholes model at the implied volatility you enter, and real prices often move differently. Results ignore commissions, fees, dividends, taxes and early assignment. SPREADVECTOR is an educational screening tool only. Results are not financial advice, investment recommendations, or solicitations to trade. Options trading involves substantial risk of loss and is not suitable for all investors. Past screening results do not predict future performance. You are solely responsible for your own trading decisions. Consult a licensed financial advisor before trading.

Get the weekly scan

Every week: a handful of cash-secured put and credit spread setups from SpreadVector's screeners, priced at that morning's scan with the date and time shown, plus one practical tip on selling options. Free.

One email a week, unsubscribe any time. No account needed. Sent for us by beehiiv; see our Privacy Policy. Educational only, not investment advice. Read the latest issue.