A long straddle combines one call and one put at the same strike; payoff grows with the size of the move away from the strike.
highlighted = computed this step
Payoff in both directions
A long straddle buys both sides at the same strike. The payoff grows with the size of the move away from the strike, in either direction. At $100.00 the payoff is $0.00.
payoff(S)=max(S−K,0)+max(K−S,0)=∣S−K∣
Payoff values
At $80.00 payoff is $20.00; at $100.00 payoff is $0.00; at $120.00 payoff is $20.00.
payoffstraddle=∣S−K∣
Payoff convention
This chart is at expiry only and shows payoff, not profit. A straddle pays two premiums, so it is profitable only when prices move enough away from strike in either direction. This is not an investment recommendation.