Spot at 100 or below
Both calls expire worthless. You lose the 7 net debit — the maximum loss on this bull call spread.
- Expiry P&L
- −7
- Max loss
- 7
Call Put Spread Calculator
Long one option and short another of the same type at a different strike. Both gain and loss are capped by the strike gap versus the net premium.
Defaults are a 100/120 bull call spread priced 10 versus 3. Click Calculate, then slide spot, days, and each implied vol. Figures are theoretical and for information only.
Type a symbol, then Load or leave the field. Spot, ~30-day historical realized vol, and a US risk-free proxy are filled when the ticker is found. Strikes and target are recentered near the new spot.
Delayed/free data. Historical realized vol is not implied vol from an options chain. Not investment advice.
New Option 1 Price:
New Option 2 Price:
How the spread P&L is calculated
A call or put spread is long one option and short another of the same type at a different strike. Net premium is V − V2 (you pay the long and collect the short). Both upside and downside are limited to the strike gap versus that net debit or credit.
Expiry P&L = Q × [max(φ(S − K), 0) − V] − Q2 × [max(φ(S − K2), 0) − V2]
- φ — +1 for a call spread, −1 for a put spread
- K — long strike; K2 — short strike
- Live P&L uses two Black-Scholes marks and the same long-minus-short difference
Each leg has its own implied vol. Defaults (call spread, V = 10 at 100, V2 = 3 at 120) imply 23.97% and 22.13%.
Worked examples
Bull call spread: long 100-strike at 10, short 120-strike at 3, one lot each. Net debit 7. The chart uses this payoff.
Breakeven at 107
Long intrinsic of 7 offsets the net debit. Below 107 the spread is still a net loser at expiry.
- Expiry P&L
- 0
- Breakeven
- K + net debit = 107
Spot at 120 or above
The strike gap is 20 and you paid 7, so the maximum gain is 13. Implied vols on the two legs are 23.97% and 22.13%.
- Expiry P&L
- 13
- Max gain
- 13
Related calculators on this site
A single long or short option is one leg. Butterflies and condors add more strikes. Vanilla pricing is the engine behind each mark.
Call and put spread FAQ
If you buy the lower strike and sell the higher strike, you want spot up — a bull call spread (the default). Swap the strikes so the short is the lower one and the same structure profits if spot falls (a bear call spread). Put spreads flip which way the intrinsic points.
For a debit call spread, max loss is the net premium paid; max gain is the strike width minus that debit. The default 100/120 call spread pays 7 and can make 13. A credit spread reverses those two numbers.
A textbook spread uses the same quantity on both legs. The form lets you type different sizes; the chart will follow whatever you enter, which can leave residual naked risk.
Each strike is inverted on its own. The 10-priced 100 call implies 23.97%; the 3-priced 120 call implies 22.13%. The sliders can move those vols independently.
Intrinsic uses strike minus spot instead of spot minus strike. A long higher-strike put versus a short lower-strike put is a bear put spread. The same net-debit arithmetic applies.
European vanilla Black-Scholes on each leg, the same engine as the option calculator. There is no smile: each leg has a single flat vol.
Disclaimer: the contents of this website are for informational purposes only and do not constitute any investment recommendation. The visitor acts at his own risk.