What's my estimated margin requirement selling a short strangle, and how undefined is my risk?

How this is calculated

• This uses the standard Reg T formula many brokers use as a baseline for uncovered equity options: the greater of (20% of stock price minus the out-of-the-money amount, plus premium) or (10% of the strike price, plus premium), per leg.
• The strangle's total margin is estimated as the larger of the two legs' individual margin requirements, plus the premium collected on the other leg, the standard convention since only one side can be tested at a time.
• Actual broker margin varies. Portfolio margin accounts calculate this differently, and some brokers apply additional requirements. Treat this as an estimate, not a quote from your broker.
• Loss on the call side of a short strangle is undefined because a stock's price has no upper limit. This tool only shows the capped loss if the stock fell all the way to zero, which is the put side's worst case.
• This is standard options margin math based on the numbers you enter, not a guarantee of what your broker will actually require.