Options calculator
Price one option leg at a time from your payoff position. ET expiry clock — equity 4:00 PM or index 9:30 AM, including 0DTE. Choose European Merton, American CRR, or Black-76; Treasury curve, SVI surface, discrete dividends, and extended Greeks. Sweep spot, strike, IV, time, rates, or dividends — every output labeled with its engine.
From payoff diagram
Edit position →Time to expiration
Premiums come from the payoff tool (market offering). Adjust expiry here or on payoff.
Multiple expiries. Shared expiry Sep 18, 2026. Calculator and scenarios price each leg on its own expiry clock. Payoff settles legs on the chosen horizon date; later legs stay open at fill-implied IV until their expiry.
| Leg 1Long 100 call | |
|---|---|
| Expiry | |
| Time left |
Expiry uses a US Eastern timestamp: pick the date, settlement clock (equity 4:00 PM or index 9:30 AM). The summary line shows hours remaining for 0DTE. Life-decay theta is expected P&L over the next step (1 day, 1 hour, or to expiry) — the same definition across all three models. Vega and extended Greeks are per one vol point unless noted.
Pricing methodology — models, cross-implementation validation, and known limitations.
Methodology updated 14 September 2026.
Educational content only. Not investment advice. Trading involves substantial risk of loss, including loss exceeding amounts invested. Trade at your own risk. Full educational disclaimer.