Broken Wing Butterfly Calculator: Payoff & Breakeven

A broken-wing butterfly calculator takes the guesswork out of pricing an asymmetric options spread by turning your strike prices and premiums into a net debit, a max profit, and two breakeven points in one pass. Unlike a symmetric butterfly, a broken wing butterfly (often shortened to BWB) uses uneven wing widths on purpose, so the risk on one side of the trade is deliberately different from the risk on the other. That asymmetry is exactly what makes the math harder to do in your head — and exactly what this options trading strategy calculator is built to solve.

What Is a Broken Wing Butterfly?

A broken wing butterfly is a long butterfly spread where the two long strikes sit at different distances from the short strike in the middle. In an equal-wing version, both wings are the same width — buy one option below the short strike, sell two at the short strike, buy one the same distance above. A BWB stretches one of those wings out, which shifts the net debit (sometimes turning it into a net credit), changes the shape of the result curve, and moves risk toward the side with the narrower wing. Traders reach for this structure when they want a directional tilt, a lower cost of entry, or both, without giving up the defined-risk profile that makes the tent-shaped payoff of a butterfly appealing in the first place. It's also described as a ratio spread with defined risk, since two short middle options are financed by a combination of long options above and below rather than left naked.

Because the wings no longer mirror each other, the position is no longer purely neutral the way a textbook neutral strategy is. It behaves like a hybrid between a plain butterfly and a credit spread, carrying a directional bias toward whichever side has the wider, cheaper wing. Some traders call the same idea a skip strike butterfly, since one wing effectively skips a strike relative to the other.

Broken Wing Butterfly vs. a Standard Butterfly Spread

A standard butterfly — sometimes called a regular butterfly or a symmetric butterfly — buys equal distances on either side of the short strike, so both tails cap out at the same maximum loss. A broken wing butterfly gives that symmetry up deliberately. The wider wing usually costs less relative to the narrower one, which pulls the net debit down and can turn the trade into a net credit. The trade-off is that the tail behind the wider wing now carries different risk than the tail behind the narrower one — sometimes more, sometimes less, depending on which side you widen and whether the butterfly wings are built with calls or puts.

Call vs. Put Broken Wing Butterfly Setups

A call broken wing butterfly buys one call below the short strike, sells two calls at the short strike, and buys one call further above — with one wing stretched wider than the other, depending on the outlook. A put broken wing butterfly mirrors this with puts: buy one put above the short strike, sell two puts at the short strike, and buy one put further below, again with one wing widened relative to the other. Both versions share the same underlying formula; the choice between the two mostly comes down to which side of the current price you expect the underlying stock to lean toward, and which option chain offers better liquidity at the strikes you need. A put broken wing butterfly is generally the more natural fit when your outlook is neutral-to-bearish, since widening the lower put wing lets you collect a credit while capping how much a further decline can cost you.

How the Broken-Wing Butterfly Calculator Works

Every input you enter into the calculator maps directly onto one leg of the trade — the same holds whether you're pricing a call broken wing butterfly, a put broken wing butterfly, or comparing both side by side. Get the strikes, premiums, and expiration right, and the calculator does the arithmetic that would otherwise take a spreadsheet and a few minutes of careful checking.

Inputs: Strike Prices, Premiums, and Expiration

You'll enter three strike prices — a lower strike, a middle strike, and an upper strike — along with the premium paid or received at each strike price, the number of contracts, and the expiration date. Because this is a broken wing structure, the calculator does not assume the distance between the lower and middle strike matches the distance between the middle and upper one; you tell it both wing widths independently. Some calculators also let you toggle between manually entered premiums and a Black-Scholes estimate driven by implied volatility and skew, which is useful if you don't yet have live quotes for every strike.

Outputs: Net Debit, Max Profit, Max Loss, and Breakeven Points

Once the inputs are set, the calculator returns the net debit — or net credit, if the credit received from the two short middle options outweighs the debit paid for the long wings — the maximum profit and where it occurs, the maximum loss on each side individually, since a BWB's two tails rarely match, and both breakeven points. A good calculator also plots a P/L Diagram so you can see the shape of the trade rather than just reading numbers off a table.

The Broken-Wing Butterfly Formula

The math behind a broken wing butterfly builds directly on the standard long butterfly formula, with one change: the upper and lower wing widths are allowed to differ. Let K1, K2, and K3 be the lower, middle, and upper strike prices, S be the underlying asset's price at expiration, and D be the net debit per share (negative if the trade is entered for a net credit).

Net Debit or Credit

$$D = P_{K1} - 2 \times P_{K2} + P_{K3}$$

where P_K1, P_K2, and P_K3 are the premiums paid or received at each strike. A positive D is the debit paid up front; a negative D is the credit received.

Max Profit and Max Loss at Expiration

Broken-wing butterfly profit equals the value of the long lower option, minus the two short middle obligations, plus the value of the long upper option, minus D. Written as a piecewise function of the underlying stock's price at expiration:

$$P/L = \begin{cases} -D \times 100 \times Qty & S \le K1 \\ (S - K1 - D) \times 100 \times Qty & K1 < S \le K2 \\ (2K2 - K1 - S - D) \times 100 \times Qty & K2 < S < K3 \\ (2K2 - K1 - K3 - D) \times 100 \times Qty & S \ge K3 \end{cases}$$

In a standard butterfly, the two flat regions below K1 and above K3 would settle at the same value, giving the classic tent-shaped payoff its symmetric base. Because K3 − K2 no longer equals K2 − K1 here, those two flat regions settle at different values instead. That gap between them is the tail risk a broken wing butterfly trades symmetry away for.

Breakeven Points

The lower breakeven is K1 + D. The upper breakeven solves (2K2 − K1 − S − D) = 0 for S, giving S = 2K2 − K1 − D, provided that value falls below K3 — if the wider wing is stretched far enough, the position never truly breaks even on that side within the sloped middle region.

Worked Example: Pricing a Call Broken Wing Butterfly on DEF Corp

Say DEF Corp is trading at $142.50 with 30 days left until the expiration you're targeting. You expect the underlying stock to drift toward the middle of your range rather than break out sharply in either direction, so you build a call broken wing butterfly around that expectation. A put broken wing butterfly on the same underlying, built with the mirrored strikes below the current price, would follow the identical arithmetic.

Setting Up the Trade

The lower wing (from $135 to $145) is 10 points wide. The upper wing (from $145 to $158) is 13 points wide — the wider, "broken" wing, and the credit spread strikes that finance the trade. Plugging the premiums into the net debit formula:

$$D = 11.40 - (2 \times 5.60) + 1.35 = \$1.55 \text{ per share} = \$155 \text{ total}$$

Calculating the Payoff at Expiration

With K1 = 135, K2 = 145, K3 = 158, and D = 1.55, the piecewise formula gives:

• If DEF settles at or below $135, the trade loses the full net debit of $155 — every call expires worthless.
• If DEF settles exactly at $145 (the middle strike, and the max profit point), the position is worth $845.
• If DEF settles at or above $158, the trade loses $455 — a bigger max loss than the downside tail, because the wider upper wing offers less protection per dollar of stock movement.

That $300 gap between the two tail losses — $155 on the downside versus $455 on the upside — is the price of stretching the upper wing. It's also exactly the kind of number worth surfacing before you ever place the order.

Reading the Breakeven Points

The lower breakeven is $135 + $1.55 = $136.55. The upper breakeven is (2 × $145) − $135 − $1.55 = $153.45. Between $136.55 and $153.45, the trade shows a profit at expiration; outside that range, the loss on the downside tail is capped at $155, while the loss on the upside tail is capped at $455.

Wing Width and Tail Risk: Where the Risk Moves

Widening one wing of a butterfly does two things at once: it changes the debit paid up front, and it changes how much the position can lose if the underlying blows through that side. A wider wing means the long option on that side is cheaper (it's further out-of-the-money), so it offsets less of the risk from the two short middle options. The narrower wing, by contrast, sits closer to at-the-money, costs more, and offsets more of the short obligation — which is why the loss on that side tends to stay closer to the plain debit.

Reducing Cost with a Net Credit

Stretch the wider wing far enough, and the credit received from the two short middle options can exceed the combined cost of both long options, flipping the debit into a credit. When that happens, the flat region on the narrow-wing side turns from a capped loss into a guaranteed minimum profit — you keep the credit if the underlying finishes on that side of the trade, no matter how far it moves. This is the mechanic behind the "eliminate risk on one side" pitch that comes up around broken wing butterflies: it isn't magic, it's the wing that's doing the work, and it applies equally to a put broken wing butterfly financed the same way.

Where the Tail Risk Moves

The trade-off is that the wide-wing side keeps real risk — often more than a symmetric butterfly would carry on either side. Before entering a broken wing butterfly, it's worth asking which direction you're more comfortable being wrong about, because that's the side you should widen. If you're bullish and want the downside protected for a credit, widen the upper wing on a put broken wing butterfly or the lower wing on a call version; if you're bearish, a put broken wing butterfly with the lower wing widened does the reverse.

The Greeks and Volatility Behind a Broken Wing Butterfly

A broken wing butterfly's sensitivity to market conditions comes from the same Greeks that describe any options trading strategy, but the asymmetry changes how they behave compared with a symmetric version.

Delta, Gamma, and Directional Bias

Delta on a broken wing butterfly isn't close to zero the way it is on a symmetric one — the wider wing skews delta toward the narrow-wing side, giving the position a real directional bias even though it's built from call options or put options that would otherwise cancel out. Gamma stays highest near the short middle strike and flips sign as the underlying crosses it, same as any butterfly, but the magnitude on each side is no longer identical. Rho's effect is usually small for a short-dated equity trade like this one, but it grows more relevant on longer-dated index positions.

Vega, Implied Volatility, and Skew

Like a symmetric butterfly, a broken wing butterfly is generally short vega near the middle strike — rising implied volatility tends to hurt the position before expiration, and volatility contraction afterward tends to help it, because the trade profits most when the underlying settles rather than swings. Traders who build a BWB for a net credit often look for elevated implied volatility and a high IV rank at entry, since richer premiums on the short middle strikes are what make the credit possible in the first place, and they'll check the volatility skew across strikes before assuming every leg is priced consistently.

Theta, Time Decay, and Probability of Profit

Time decay generally works in your favor once the trade is on, since the two short middle options lose time value faster than the two long wings as expiration approaches — provided the underlying stays reasonably close to the middle strike. That's the same time decay dynamic a symmetric butterfly relies on; the broken wing structure doesn't change its direction, only how much of it you're exposed to on each side. Entering for a net credit also raises the position's probability of profit (POP), since a credit gives you a profitable outcome on the narrow-wing tail even if the underlying never approaches the middle strike.

Black-Scholes Pricing Behind the Numbers

When a calculator lets you enter implied volatility instead of manual premiums, it's typically using a Black-Scholes model to price each leg — European-style options exercise, constant volatility, a constant risk-free rate. That's a simplification real markets don't always honor, but it's close enough to sanity-check whether a quoted premium looks reasonable before you place the trade.

Sizing Up a Real Setup: PVX Robotics After a Guidance Cut

Eighteen months into trading options part-time, Mara has learned to wait for a specific setup before reaching for a broken wing butterfly: a stock that's just repriced sharply and now needs time to digest the move. PVX Robotics is exactly that kind of setup — after cutting full-year guidance on a Tuesday morning call, the stock gapped down and has spent the past six sessions grinding sideways around $68.15, with 30-day implied volatility still sitting near the top of its one-year range even as the daily swings shrink.

With 24 days left until the next monthly expiration, Mara pulls up PVX's option chain and builds a call broken wing butterfly: buy one $60 call for $9.65, sell two $68 calls at $4.20 each, and buy one $75 call for $0.85 — a narrower seven-point upper wing against an eight-point lower wing, deliberately keeping less risk on the side she considers less likely.

Running the strikes through the calculator confirms the net debit: $9.65 minus $8.40 in premium collected across the two short calls, plus $0.85, comes to $2.10 per share, or $210 for one contract. The calculator's output table shows the trade's ceiling too — a maximum profit of $590 if PVX settles exactly at $68 at expiration, against a $210 loss if the stock drops back below $60 and a smaller $110 loss if it rallies past $75.

That $100 gap between the two tail losses is the number Mara actually cares about. It confirms the narrower upper wing is doing its job: capping the less-likely upside scenario more tightly than the downside one she's positioning against. With her breakevens sitting at $62.10 and $73.90, she sets a standing order to close the trade automatically once it captures $300 of profit — roughly half the maximum — rather than holding to expiration and hoping the stock pins exactly at $68.

Choosing Strike Prices for Your Broken Wing Butterfly

Strike selection is where most of the options strategy actually happens; the calculator just confirms the math afterward.

Picking Your Long Strike, Short Strike, and Middle Strike

The middle strike should sit where you expect the underlying asset to land at expiration — that's where max profit occurs, so it deserves the most thought. The short strike is the same price here, since you're selling two options there. Your long strike choices on either side set the wing widths: keep one close to that center price to hold down risk on that side, and push the other further out if you want to reduce cost or collect a credit, accepting more tail risk on that side in exchange.

Balancing Wing Width Against Premium Received

A wider wing isn't automatically better just because it lowers the debit. Every extra point of wing width increases the loss on that side by roughly the same amount it reduces the cost of the long option. Before widening a wing, compare the reduction in cost against the increase in that side's loss potential — if the trade-off doesn't match your risk tolerance, a narrower wing, and a higher net debit, may be the better fit.

When to Use a Broken Wing Butterfly Options Strategy

A broken wing butterfly rewards a specific market view within an options trading strategy: you expect the underlying to land near a particular price, but you're not equally comfortable being wrong in both directions. It's a common tool for traders building an income-focused portfolio management approach around defined-risk, high-probability trades rather than pure directional bets.

Ideal Volatility Conditions

This structure tends to work best when implied volatility is elevated enough at entry to make the short middle premiums worth collecting, then contracts toward expiration. A stock stuck in a quiet, range-bound pattern after a volatility spike — post-earnings drift is the classic example — is a textbook setup, and it's worth checking technical indicators and recent market sentiment before committing to the trade.

Range-Bound vs. Directional Markets

In a genuinely range-bound market, a symmetric butterfly and a broken wing butterfly perform similarly near the middle strike, but the broken wing version costs less, or pays you, to enter. In a market where you have a mild directional lean, the broken wing structure lets you express that lean without fully committing to a directional spread — you keep defined risk on both sides, just uneven defined risk. A put broken wing butterfly tends to fit a cautiously bearish read on market conditions, while a call version fits a cautiously bullish one.

Common Mistakes When Trading a Broken Wing Butterfly

• Assuming both tails carry equal risk, then being surprised by the size of the loss on the wide-wing side.
• Ignoring how far the wider wing is stretched relative to the narrower one, which is what actually sets the risk-reward.
• Forgetting there are two short options at the middle strike, not one, when estimating margin or assignment exposure.
• Entering with low implied volatility, leaving little premium at the short strike to fund the wider wing.
• Overlooking commissions and other fees on what is a four-leg trade, which can meaningfully eat into a small net credit.
• Ignoring upcoming dividends on the underlying stock, which can shift early-assignment odds around ex-dividend dates.

Assuming a Broken Wing Butterfly Has Equal Risk on Both Sides

This is the single most common misread of the strategy, for a call broken wing butterfly and a put broken wing butterfly alike. A symmetric butterfly's balance makes "the same risk on both sides" a fair mental shortcut; a broken wing butterfly breaks that shortcut on purpose, and treating the two tails as interchangeable is how traders get caught off guard by a loss that's two or three times larger than they expected.

Managing and Closing a Broken Wing Butterfly Position

Most broken wing butterflies aren't held to expiration. Managing the trade actively tends to produce steadier results than waiting for the final settlement price, whether you're running a call broken wing butterfly or a put broken wing butterfly.

Order Types, Stop-Loss Orders, and Profit-Taking Targets

A common approach is to close once the position captures roughly 25% to 50% of its max profit, rather than holding out for the full amount at the exact middle strike — a target that's easy to hit exactly at expiration but hard to land on with time still remaining. Setting a defined take-profit level ahead of time, along with stop-loss orders tied to a percentage of the debit paid, keeps the exit decision mechanical instead of emotional. Limit orders, rather than market orders, are worth using on every leg of a four-option order types like this one, since a wide bid-ask spread on any single strike can quietly erode the credit received.

Adjusting or Rolling the Trade

If the underlying drifts toward the wide-wing side, some traders roll the threatened long option further out, effectively widening that wing again and collecting additional credit received to offset the growing risk. Others use a related risk management technique, such as a protective collar on shares of the underlying stock if they're also holding it, to cap losses outside the options structure entirely. Whichever approach you use, having a trading platform that lets you see the live P/L Diagram of the position — not just the theoretical one from entry — makes these decisions considerably easier, and is a basic requirement for anyone serious about options pricing and risk management as part of their broader investing.

Broken Wing Butterfly vs. Credit Spread

Both a broken wing butterfly and a credit spread can be built to collect premium up front while keeping risk defined, which is why traders often weigh a broken wing butterfly spread against a standalone spread.

Debit Spread and Credit Spread Together

A broken wing butterfly is, structurally, a debit spread and a credit spread stitched together at the same short strike: the narrower side behaves like a debit spread, and the wider side behaves like a credit spread wide enough to finance it. A standalone credit spread only has one side to manage and one breakeven point, which makes it simpler, but it also gives up the extra profit potential a butterfly's peak offers if the underlying lands exactly where you expect. The broken wing structure trades that simplicity for a shot at a considerably larger peak profit if the underlying settles near the middle strike, at the cost of a second breakeven point and a less forgiving margin for error.

One more distinction worth noting: early assignment risk. With American-style options, the short calls at your middle strike can, in principle, be assigned before expiration — particularly if the underlying trades deep in the money near one of its ex-dividend dates and pays a meaningful dividend. European-style options, common on many index products, remove that risk entirely since they can't be exercised before expiration. Assignment risk on American-style contracts is rarely a problem for out-of-the-money short strikes, but it's worth checking your option chain's exercise style, and the underlying's dividend schedule, before assuming it can't happen to you.

Whichever version of the trade you build — a call or put broken wing butterfly, sometimes just called a butterfly spread calculator setup, financed for a credit or paid for as a small debit — running the exact strikes and premiums through the calculator before you place the order is the fastest way to confirm the numbers match what you intended in your options trading, rather than finding out from the fill.