Options Spread Calculator
For a bull call spread, from the two call strike prices and premiums compute the net premium, max profit, max loss and break-even.
Input Data
Results
At a glance:A bull call spread buys a lower-strike call and sells a higher-strike call. Net premium = long premium − short premium. Max profit = (short strike − long strike) − net premium; max loss = net premium; break-even = long strike + net premium. The spread gains when the underlying rises but caps the upside at the short strike.
Formula
Net premium = long premium − short premium.
Max profit = (short strike − long strike) − net premium.
Max loss = net premium; break-even = long strike + net premium.
$$$\\text{Net} = P_{buy} - P_{sell}$$$$$$(K_{high} - K_{low}) - \\text{Net}$$\\text{Net}$$$$$$K_{low} + \\text{Net}$$$How to Use
- Enter the long (lower) strike and the premium paid.
- Enter the short (higher) strike and the premium received.
- Read the net premium, max profit, max loss and break-even.
FAQ
What is a bull call spread and why structure it this way?
A bull call spread is a moderately bullish strategy of two calls with the same expiry: buy a lower-strike call (long call) and sell a higher-strike call (short call). The point is to use the premium received from the short call to subsidise the cost of the long call. Buying a single call has unlimited upside but a high premium and risks losing it all if the underlying barely moves; the spread offsets part of that cost with the premium received, lowering your net cost and your maximum loss. The trade-off is that the short (higher-strike) call caps your upside — once the underlying rises past that higher strike, the extra profit is offset by the obligation on the short call. So it suits the view 'I think it rises, but only modestly'. It trades unlimited upside for lower cost and a defined risk cap.
How are the max profit, max loss and break-even computed?
The pay-off is clear and the four numbers are direct. Net premium (net cost) = long premium − short premium; with a lower-strike long (pricier) and higher-strike short (cheaper), this is usually a net debit. Example: long strike 100 paying 5, short strike 110 receiving 2 → net premium = 3. Max loss = net premium = 3, occurring when the underlying expires below the lower strike (both calls worthless) — you lose only the net cost. Max profit = (short strike − long strike) − net premium = (110 − 100) − 3 = 7, occurring when the underlying expires at or above the higher strike. Break-even = long strike + net premium = 100 + 3 = 103: at exactly 103 the long call's intrinsic value (3) offsets the net cost, breaking even; above 103 you profit. So: pay 3, risk 3, profit up to 7, profitable above 103 — a fully defined risk/reward.
What should I watch for versus real options trading?
This calculator shows the theoretical per-share expiry pay-off of a debit bull call spread. Real trading adds: (1) contract multiplier — options are per board lot (e.g. 100 shares), so actual P&L = per-share result × multiplier × contracts; (2) transaction costs — two opening legs plus closing, with commissions and bid-ask spreads eroding the already-capped profit; (3) pre-expiry value changes — time decay (theta), implied volatility (vega) and spot moves change the mark-to-market before expiry; (4) early assignment risk on the short call, especially American options near ex-dividend; (5) dividends and corporate actions affecting pricing; (6) this calculator covers only the debit bull call spread, not bear spreads, credit spreads or put spreads. Use it to understand the structure, not as trading advice.
How does a bull call spread (debit) differ from a bull put spread (credit)?
Both are moderately bullish, but structured differently. A bull call spread (debit): two calls — buy lower-strike, sell higher-strike — usually a net debit paid upfront; max loss is that net cost, max profit is the strike gap minus the net cost, and it needs the underlying to rise. A bull put spread (credit): two puts — sell higher-strike put, buy lower-strike put — usually a net credit received upfront; max profit is that credit (received if the underlying stays above the higher strike and both puts expire worthless), max loss is the strike gap minus the credit. The pay-off shapes are similar (both capped, moderately bullish), but the debit spread 'pays first, profits if the underlying rises', while the credit spread 'collects first, profits if the underlying does not fall'. Choice depends on your view of time decay and volatility, and cash-flow preference.
Does the Hong Kong market have these spreads and how are they taxed?
Yes — single-stock and index options are traded in Hong Kong (notably HKEX), and bull call spreads are a standard retail strategy. On tax, Hong Kong has no general capital gains tax, so individuals' profits on exchange-traded options are typically not taxed; but the treatment differs for a business/trading activity, and cross-border or non-resident situations vary. Note also that Hong Kong's options market and the availability of certain strikes/liquidity differ from the US, so check the contract specifications and margin rules on HKEX. This calculator is for educational estimation only; consult a licensed practitioner before trading.
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References
Content review: Calculatorism Finance Team. Results are for reference only; please refer to the relevant authorities for the official figures.