Butterfly Spread Calculator
Enter bid & ask per leg — or fetch live quotes automatically
📡 Live Quote Fetch
Ready
⚪ No key saved
Mode:
Leg inputs
Buy
×1
ITM strike (K1)
6.50
Bid
—
Mid
—
Ask
—
Spread
—
Sell
×2
Middle strike (K2)
2.50
Bid (×2)
—
Mid (×2)
—
Ask (×2)
—
Spread
—
Buy
×1
Far OTM wing (K3)
0.75
Bid
—
Mid
—
Ask
—
Spread
—
Fill range
Net debit — what you could actually pay
Best (bid buys / ask sells)
—
Mid price
—
Worst (ask buys / bid sells)
—
Best
Mid
Worst
Best fill
—
Mid (fair price)
—
Worst fill
—
Breakdown at mid
+ Buy ITM (K1)—
+ Buy far wing (K3)—
− Sell ×2 mid (K2)—
= Net fair price—
Butterfly Spread Calculator
Enter bid & ask per leg — or fetch live quotes automatically
📡 Live Quote Fetch
Ready
⚪ No key saved
Mode:
Leg inputs
Buy
×1
ITM strike (K1)
6.50
Bid
—
Mid
—
Ask
—
Spread
—
Sell
×2
Middle strike (K2)
2.50
Bid (×2)
—
Mid (×2)
—
Ask (×2)
—
Spread
—
Buy
×1
Far OTM wing (K3)
0.75
Bid
—
Mid
—
Ask
—
Spread
—
Fill range
Net debit — what you could actually pay
Best (bid buys / ask sells)
—
Mid price
—
Worst (ask buys / bid sells)
—
Best
Mid
Worst
Best fill
—
Mid (fair price)
—
Worst fill
—
Breakdown at mid
+ Buy ITM (K1)—
+ Buy far wing (K3)—
− Sell ×2 mid (K2)—
= Net fair price—