Bull Call Spread Calculator
A bull call spread buys one call and sells a higher one, cutting the cost of a long call in exchange for a capped gain. Max loss is the net debit; max profit is the strike width minus that debit. Enter both strikes and premiums to see it.
The arithmetic
The default buys the $100 call for $3.50 and sells the $110 call for $1.20 — a net debit of $2.30, or $230.
- Max loss = net debit = $230, at any price at or below $100.
- Max profit = (strike width − net debit) × 100 = (10 − 2.30) × 100 = $770, at any price at or above $110.
- Breakeven = lower strike + net debit = $102.30.
- Risk/reward = $770 against $230, a little over 3:1 — but only if the stock clears $110.
What the short leg buys you
Compare this against the long call on the same strike. The plain call costs $350 and breaks even at $103.50. Selling the $110 call cuts the cost to $230 and pulls breakeven down to $102.30. You have made the trade cheaper and easier to win.
The price is the flat ceiling above $110. If the stock finishes at $130, the spread pays $770 and the plain call would have paid $2,650. You sold the tail. Whether that was smart depends entirely on whether you had a real reason to expect a move past $110 — and most of the time, traders buying calls do not.
Choosing the width
A narrow spread is cheap, has a high maximum return on risk, and needs the stock to travel almost the whole distance to pay out. A wide spread costs more and behaves increasingly like a plain long call. Widen the short strike on this page and watch three things move together: the debit rises, the breakeven rises, and the max profit rises faster. There is no free lunch in the geometry, only a choice about which risk you want.
Time decay cuts both ways here
Unlike a long call, a debit spread is not purely hurt by the passage of time. The short leg decays in your favour and partly offsets the long leg's bleed. In a stock that goes nowhere, a bull call spread loses money more slowly than a naked long call — a real, if modest, advantage that the expiration chart cannot display.
Where the 100x multiplier comes from
Product specification, not convention: OCC defines a standard equity option as covering 100 shares, premium quoted in points where one point is $100[1] — so a $1.85 premium costs $185, and every payoff here applies that multiplier to the leg structure.
One exception is worth knowing about: adjusted contracts, covered on the options profit calculator.
Calculating it is the easy half
The spread prices out in one subtraction. The payoff is arithmetic — anyone can run it. What it cannot show is whether you believed the trade when you put it on, or are describing a winner picked out of a month of noise.
That is the gap kappi closes: the position committed before the fact, sealed and timestamped on a log nobody can edit afterwards. A screenshot of this chart proves you can use a calculator; a sealed commit proves you took the trade. $15/month, no free tier.
Sources
Frequently asked questions
What is the maximum loss on a bull call spread?
The net debit paid, times 100 per spread. On a $100/$110 spread costing $2.30 net, that is $230 — incurred at any price at or below the lower strike.
What is the breakeven on a bull call spread?
The lower strike plus the net debit per share. A $100/$110 spread costing $2.30 breaks even at $102.30.
Is a bull call spread better than a long call?
It is cheaper and breaks even sooner, but caps your gain at the upper strike. It is better whenever you expect a moderate move and worse whenever the move turns out to be large.
What happens if the stock finishes between the strikes?
The long call has intrinsic value and the short call expires worthless. Your profit is the stock price minus the lower strike minus the net debit, per share.