Free Reverse Conversion Calculator

What Is a Reverse Conversion (Reversal)?

A reverse conversion — also known as a reversal — is a three-leg options arbitrage strategy designed to exploit mispricings between a stock and its options. The position consists of three simultaneous trades: selling the underlying stock short, buying a call option, and writing (selling) a put option at the same strike price and expiration date.

When put-call parity holds perfectly, the combined payoff of the long call and short put (a "synthetic long") exactly replicates owning the stock. By shorting the actual stock and holding the synthetic long, any deviation from parity can be captured as a risk-free profit. In practice, transaction costs, dividends, borrowing fees, and early-assignment risk mean that true risk-free arbitrage is rare — but the strategy remains a cornerstone of professional options market-making.

How a Reverse Conversion Works

The three legs of a reverse conversion work together to create a market-neutral position:

• Short Stock: You sell shares of the underlying stock short, receiving cash proceeds. This leg has a delta of −1 per share.
• Long Call: You buy a call option at a chosen strike price. This gives you the right to buy the stock at the strike, providing upside protection for the short stock position.
• Short Put: You sell a put option at the same strike price and expiration. This obligates you to buy the stock at the strike if assigned, providing downside exposure that mirrors the short stock's gain.

At expiration, regardless of where the stock price ends up, the synthetic long (long call + short put) offsets the short stock position. The net P/L is determined entirely by the initial credits and debits when the trade was opened.

How to Calculate Reverse Conversion Profit and Loss

Understanding the math behind a reverse conversion is essential for evaluating whether an arbitrage opportunity exists:

• Short Stock P/L: (Shorted Price − Stock Price at Expiry) × Number of Shares.
• Long Call P/L: Max(0, Stock Price − Strike Price) × Contracts × 100 − Call Premium Paid × Contracts × 100.
• Short Put P/L: Put Premium Received × Contracts × 100 − Max(0, Strike Price − Stock Price) × Contracts × 100.
• Total P/L: Short Stock P/L + Long Call P/L + Short Put P/L.
• Net Premium: Put Premium Received − Call Premium Paid. A positive net premium means you receive cash from the options leg.

How to Use This Reverse Conversion Calculator

1. Enter the Stock Symbol: Type a ticker and click "Get Price" to fetch the current stock price and available option chains automatically.
2. Select an Expiration Date: Choose from available expiration dates. The calculator loads both call and put chains for the selected date.
3. Pick a Strike Price: Select a call contract from the chain — the calculator auto-selects the matching put at the same strike. Both options must share the same strike for a proper reverse conversion.
4. Set the Short Stock Parameters: Enter the shorted price (defaults to current price) and number of shares (typically 100 per option contract).
5. Adjust Contracts: Set the number of call and put contracts. For a standard reverse conversion, use 1 contract each per 100 shares shorted.
6. Review Results: The calculator instantly displays max profit, max loss, breakeven, net Greeks, and an interactive payoff diagram showing both expiry and current P/L curves.

Why Use Our Reverse Conversion Calculator?

Put-Call Parity and Reverse Conversions

Put-call parity is the theoretical foundation of the reverse conversion strategy. The relationship states:

C − P = S − K × e^(−rT)

Where C is the call price, P is the put price, S is the stock price, K is the strike price, r is the risk-free interest rate, and T is the time to expiration in years. When this equation does not hold, an arbitrage opportunity exists.

A reverse conversion is profitable when the synthetic long stock (long call + short put) costs less than the actual stock price minus the present value of the strike. In other words, when:

C − P < S − K × e^(−rT)

The trader shorts the overpriced stock and buys the underpriced synthetic, locking in the difference as profit.

Risks and Considerations

While reverse conversions are theoretically risk-free, several real-world factors can erode or eliminate the arbitrage profit:

• Early Assignment: American-style short puts can be assigned early, especially around ex-dividend dates. Early assignment forces you to buy shares and close the short stock position prematurely.
• Dividend Risk: If the stock pays a dividend while you are short, you must pay the dividend to the lender. This cost reduces your profit.
• Borrowing Costs: Short selling requires borrowing shares, which incurs a stock loan fee. Hard-to-borrow stocks can have significant borrowing costs.
• Transaction Costs: Commissions, bid-ask spreads, and exchange fees across three legs can quickly consume a small arbitrage profit.
• Margin Requirements: Short stock and short put positions require margin. The capital tied up in margin reduces the effective return on the trade.

Reverse Conversion vs. Conversion

A conversion is the mirror image of a reverse conversion. While a reverse conversion shorts the stock and creates a synthetic long, a conversion buys the stock and creates a synthetic short (short call + long put). Both strategies exploit put-call parity violations but from opposite directions:

• Reverse Conversion: Short stock + Long call + Short put. Profits when the synthetic long is cheaper than the stock.
• Conversion: Long stock + Short call + Long put. Profits when the synthetic short is cheaper than shorting the stock.