Trade SPX 0DTE like the real open-to-close grind.

Cash-settled European index options, $100 multiplier, same-day expiry. Live bid/ask chain, Greeks, theta decay, naked short margin, and settlement at the close — compressed into one playable session.

Full 0DTE chain

Calls & puts around ATM with smile IV, bid/ask, delta & theta.

Time decay that hurts

Black–Scholes pricing with real theta crush into the 4:00 close.

Path-dependent SPX

GBM + jumps + regime shifts. No two sessions play the same.

Long & short

Buy premium or sell naked with simplified SPX margin holds.

Start a session

Choose capital. Session clock is 9:30–4:00 ET at selectable speed (default 15×; use 60–120× for a quick day).

Educational simulation only — not real markets, not advice, not affiliated with Cboe.