Cash-secured put calculator
Sells a put, with cash set aside to buy the shares if assigned. Enter your strikes and price to see the maximum profit, maximum loss, breakeven, profit chance and expected value.
Leave the price empty to estimate it from implied volatility. Results are per contract (100 shares), held to expiration.
Estimated credit: $41.54 per contract (from implied volatility; type your real price above)
Free, no account. The app adds volatility skew, exit plans, position sizing and a plain-English verdict.
How to use the cash-secured put calculator
- Enter the stock's price, the days left until expiration and the implied volatility from your option chain.
- Enter each strike. Then type the credit you'd receive per share, or leave it empty for an estimate.
- Add the stock's realized volatility to see expected value: what the trade makes on average if the stock keeps moving the way it has been.
Worked example
Say a stock trades at $100, options price in 25% implied volatility, and the stock has really been moving about 20% a year (its realized volatility). With 30 days to expiration, a cash-secured put at strike 92 collects about $0.42 per share, or $41.54 per contract.
- Max profit: $41.54
- Max loss: $9,158.46
- Breakeven: $91.58
- Profit chance, market-implied: 88.3%
- Expected value with 20% realized volatility: +$23.67 per contract
The expected value is positive here only because the stock is assumed to move less than options price in (20% vs 25%). If it moves more, the same trade can have negative expected value. That gap between implied and realized volatility is what the full app checks first.
What is a cash-secured put?
A cash-secured put sells one put and keeps enough cash to buy 100 shares at the strike. It's the same payoff as a naked put.
How it makes or loses money
If the price stays above the strike, you keep the credit. Below it, you lose point for point, down to the strike price if the stock went to zero.
When traders use it
Used by traders who'd be happy to own the shares at the strike, or who want income with a bullish lean.
Profit and loss at expiration
- Max profit: the credit
- Max loss: strike minus the credit (if the price went to zero)
- Breakeven: strike minus the credit
The Greeks
| Greek | Sign |
|---|---|
| Delta | + |
| Theta | + |
| Vega | − |
| Gamma | − |
What to watch out for
- Crashes hit hardest: the loss below the strike is like owning the shares.
- On stocks, early assignment can happen when the put is deep in the money.
Questions
What is the max profit on a cash-secured put?
The credit. In the example above that's $41.54 per contract.
What is the max loss on a cash-secured put?
Strike minus the credit (if the price went to zero). In the example above that's $9,158.46 per contract.
How do you calculate the breakeven of a cash-secured put?
Strike minus the credit. The calculator works it out from your strikes and price.
What does "profit chance" mean here?
It's the market-implied chance that the trade finishes with any profit at expiration, if the stock moves as much as implied volatility prices in. It assumes you hold to expiration and uses one volatility for every strike. A high profit chance doesn't mean a good trade: small, frequent wins can still lose money overall if the losses are large.
What's the difference between implied and realized volatility?
Implied volatility is how much movement option prices assume. Realized volatility is how much the stock has actually been moving. Option sellers tend to come out ahead on average when realized stays below implied, and buyers when it runs above. Expected value in this calculator uses the realized volatility you enter.
Is a cash-secured put a good trade?
This calculator can't tell you that, and neither can anyone who doesn't know your account, goals and risk tolerance. It shows the math for the numbers you enter. Whether those numbers hold up depends on the price you actually get, how the stock moves and how you manage the trade.